GB2037952A - Spherical valve assembly and seal - Google Patents

Abstract

A spherical valve structure comprising a valve housing (2), a spherical valve element (10), seals (11, 12) for said valve element (10) and a pivotable control rod (13) with a knob (17) or lever, in which the valve housing (2) may be of a one-piece construction. The inside diameter of the bore in the valve neck (3) accommodating said control rod (13) is dimensioned to allow the spherical valve element (10) and related seals (11, 12) to be inserted into a chamber (9) in said valve housing (2). <IMAGE>

Description

SPECIFICATION Spherical valve assembly and seal This invention relates to a spherical valve assembly and a seal therefor, the term "valve" applying herein to any flow control, shut-off and the like device, such as is commonly employed in fluid delivery lines or ducts.

Known are several current spherical valve structures which feature in common a two-piece valve housing construction, namely one piece or part comprising the seat accommodating the spherical valve element, which part also includes the valve "neck" and a fluid communication fitting, and another part provided with the other valve port, said latter part being threadedly engaged with the former part. In these known types, the inner front face of the threaded fitting of the part including just a single port forms, when assembled, one of two seats accommodating respective seals for the spherical valve element. In conventional solutions, the valve element control member, termed "rod", may be associated with a knob or a lever which is pivotable between two travel limit positions through an angle which is generally df 90 degrees.

While spherical valves are made up of parts which provide for a simple operational mode, high precision machining is involved in their construction.

Moreover, conventional spherical valves exhibit several drawbacks and disadvantages, the most important whereof are that: - the valve construction is an expensive one, because two threaded portion must be provided for associating the two parts forming the valve housing together; - the assembling procedure is a timeconsuming operation, since additionally to the time required for assembling and sealing the two parts which make up the valve housing, the tight fit of the same has to be checked; - the seating of the spherical valve element and its seals is not defined uniquely, but rather by tightening the two parts together, which may result, on the one hand, in a leaky valve when operated, and on the other hand, in uneven sizing of the seats involved;; it happens that, upon assembling said vavles to the lines, since the same are generally required to take a definite position with respect to the lines for convenience of handling the control knob or lever, the two parts of the valve may become shifted angularly with respect to each other, thus affecting the fluid tightness of the valve assembly.

This invention sets out to remove the aforementioned disadvantages of conventional valves by providing a spherical valve which affords: - a simpler and quicker manufacturing and assembling procedure; - constant and reproducible dimensions of the spherical valve element seats: and - prevention of leakage through the valve.

According to one aspect of this invention, there is provided a spherical valve assembly comprising a valve housing defining a valve chamber provided with opposed seats surrounding entry and exit ports of the chamber, annular seals located on said seats and a spherical valve element mounted between said seals, and a control element connected to said valve element and located in a bore extending through a wall of said housing and opening into said chamber, the bore being dimensioned to allow at least the spherical valve element to be inserted therethrough into said chamber.

Advantageously, according to another aspect of the invention, there are provided means for covering said seals from the inside.

According to a further adavantageous aspect of this invention, the seals associated with the spherical valve element have an elongated crosssection which is also advantageously symmetrical.

Further features, advantages and details of the spherical valve according to the invention will be more ciearly apparent from the following description, to be taken in conjunction with the accompanying drawings, in which: Figure 1 is a longitudinal mid-sectional view through a spherical valve assembly according to this invention; Figure 2 shows, to a reduced scale with respect to Figure 1, a perspective view of the valve assembly of Figure 1, the knob being represented therein prior to its assembly; and Figure 3 is a bottom view of the knob of Figure 2 above.

With reference to the figures of the drawing, a spherical valve assembly embodying this invention is generally indicated at 1. It comprises a housing 2 which, in accordance with a preferred embodiment of this invention, is of a one-piece construction. Said housing 2 includes a neck portion 3 defining a bore communicating with the chamber 9 in the housing 2 and two end fittings or connective portions 4, 5 which, in the embodiment illustrated, are provided with external threads, although any suitable design will be satisfactory in actual practice, such as a single taper with O-ring, male pipe threads, female pipe threads, hose connection fitting, soldered connection copper pipe fitting, S.A.E. standard fitting etc. In Figure 1, for the sake of completeness, there are shown for each fitting of the body 2, a ring seal 6, an outer fitting 7, and a retaining ring 8.The chamber 9 defined by the housing 2 accommodates the spherical valve element 10 therein, interposed seals 11, 12 being located on opposed seats defining entry and exit ports.

The numeral 13 denotes the control rod or element, which includes a ring seal or gasket 14 and a shank 1 5 engaging a specially provided seat 1 6 in the control knob 17 and a further shank 1 spa engaging in a further seat 1 6a in the valve element 10. The upper edge of the neck 3 of the valve is formed with detents or stops 18, 1 9 cooperating with lugs 20, 21 internal to the knob 17 such as to allow the latter to be turned through, for example, 909. The drawing also shows at 22 a snap ring, and at 23 an anti-friction material washer. The snap ring 22 is accommodated in a respective seat 24 in the bore in the neck 3.

As can be observed in Figure 1, the crosssectional configuration of the seals 11, 1 2 is axially elongated or more extended longitudinally, it being also symmetrical about a radial plane.

It is further evident how the spherical valve element 10 can be easily introduced into its chamber 9 from above, through the bore in the neck 3 of the valve 1 either after the seals have been located on their seats or as a unit with the sea Is.

The seats for the seals 11, 12 are in the form of machined undercuts, thereby they are easily made in a quick manner without being committed to a predetermined profile. Such seals, 11 and 12, are subjected upon insertion to an elastic deformation thus affording a correct positioning of the spherical shutter 1 0.

Dotted lines in Figure 1 indicate covering elements applied from the inside onto the seals 11, 12, which may be advantageous in some applications involving fire hazards.

As can be inferred from the drawings, the assembling of the valve, or the like device, according to this invention, is performed in a very short time, and by virtue of the symmetrical design of the seals 11, 12 no problems are encountered if the seals are interchanged.

It will be apparatent from the foregoing that the solution proposed by this invention effectively achieves the object set forth in the preamble, as well as the advantages thereof.

More specifically, any problems relating to the fluid tight assembling of the valve are prevented, while ensuring complete reproducibility of the dimensions of the chamber 9 accommodating the spherical shutter 10 with the seals 11, 12. The assembling of the rod 13, as well as of the ancillary parts 22, 23 and 17, is also carried out in a quick and failsafe manner. Manufacturing costs are reduced considerably, while at the same time, the desired geometrical engagement of the seals 11, 12 with respect to the accommodating chamber 9 is accomplished in an accurate manner.

In actual practice, quite satisfactory results have been obtained through the use of seals 11, 12 made of rubber. Obviously, it is just as possible to use any other materials having a sufficient degree of deformability, as well as seals including inserts of the grommet type, either in the form of toroidal O-rings or spiral wound filaments, or the like, or to utilize composite materials providing, for example, an inner ring or liner of an elastic material and an outer ring or shell which is Teflon coated.

In putting the invention into practice any individual part may be replaced with another technically and function-wise equivalent part, or part having a different geometrical shape, while the cited control knob may be replaced with a level member, and the end fittings of the valve body may be given any desired shape.

Furthermore, the dimensions and materials may be selected as desired to suit individual application requirements.

All the features derived from the foregoing description, appended claims and accompanying drawing may be considered relevant to the invention, either singly or in any combination, even though such features may not be explicitly mentioned in the following claims.

Claims (11)

1. A spherical valve assembly comprising a valve housing defining a valve chamber provided with opposed seats surrounding entry and exit ports of the chamber, annular seals located on said seats and a spherical valve element mounted between said seals, and a control element connected to said valve element and located in a bore extending through a wall of said housing and opening into said chamber, the bore being dimensioned to allow at least the spherical valve element to be inserted therethrough into said chamber.

2. A spherical valve assembly according to claim 1, wherein said seals have an axially elongated cross-sectional configuration and, preferably, are symmetrical about a radial plane.

3. A spherical valve assembly according to claim 1 or claim 2, wherein the cross-sectional configuration of the said seals or the material used therefor, is such as to confer to said seals the required degree of elastic deformation to allow the spherical valve element to be positioned therebetween after they have been placed on their seats in the said chamber.

4. A spherical valve assembly according to any one of the preceding claims, wherein said control element is for rotating said spherical valve element, includes a seal acting on said bore, and a retaining means cooperating with associated stop means on the bore.

5. A spherical valve assembly according to claim 4, wherein the retaining and stop means comprise a snap ring accommodated in a related seat provided in said bore, there being further provided means adapted for facilitating the sliding movement between said snap ring and a flange on said seal acting on the bore.

6. A spherical valve assembly according to any preceding claim, wherein said control element is formed with a recess accommodating a spring acting at one end against the bottom of said recess, and at the other end on the bottom of a seat provided in said spherical valve element for receiving said control element.

7. A spherical valve assembly according to any preceding claim, wherein adjacent to the seats for said seals of said spherical valve element and on the inside side thereof, fire preventing lugs are provided.

8. A spherical valve assembly according to any preceding claim wherein a knob or lever is mounted on said control element.

9. A spherical valve assembly according to any preceding claim wherein said housing is of a onepiece construction.

10. A spherical valve assembly substantially as hereinbefore described and illustrated in the accompanying drawings.

11. A seal, for use in valves and the like of the spherical type, as defined in any preceding claim, and including reinforcement inserts and/or an outer coating.