LIMITING VALVE AND VALVE ASSEMBLY

[0001] The present invention relates to a limiting valve for a fluid flow, for example water, and an assembly comprising such a valve.

[0002] It is known to use flow limiting valves, used primarily to stabilise, with respect to the transit direction of the fluid, a fluid flow downstream of the valve itself.

[0003] A particular valve type includes an O-ring of flexible material which, upon reaching a given flow speed, is deformed by the fluid thereby partially obstructing a passage which connects a duct portion upstream and a duct portion downstream of the valve: the greater the speed, the greater the deformation of the CD- ring, the greater the obstruction of s-a ^' id passage.

[0004] A valve of this type is for example known from document DE102011120008A1.

[0005] However, the limiting valves of the prior art have the drawback that the O-rings used work only within very narrow ranges of flow speed. In fact, the material of which they are made allows limited deformations, which are not adjustable at will in a quite large range of flow speed. This is mainly due to the physical limitations intrinsic to the flexibility of the materials used. [0006] The present invention falls within this context, proposing to provide a limiting valve capable of covering a wider range of flow speeds compared to conventional valves, and in particular designed to allow obtaining two or more limit interception stages, when the flow speed of the fluid gradually increases.

[0007] Such an · object is achieved by a limiting valve according to claim 1, and by a valve assembly according to claim 12. The dependent claims describe preferred embodiment variants.

[0008] The object of the present invention will now be described in detail, with the aid of the accompanying drawings, in which:

[0009] - figures 1 and 6 show a perspective view, respectively with combined parts and with separated parts, of a limiting valve object of the present .invention, according to a possible variant;

[0010] - figures 2 and 5 show two plan views, a front one and a reverse one, of the valve in figure 1;

[0011] - figures 3 and 4 show sections along planes III-III and IV-IV shown in figure 2;

[0012] - figures 10, 7 and 9 show two perspective views from opposite sides and an exploded view, respectively, of an assembly of the present invention, according to one embodiment ; [0013] - figure 8 shows a section along plane VIII-VIII of the assembly in figure 10, wherein the left half of such a figure shows an interception configuration of the check valve, while the right half shows a transit configuration thereof.

[0014] With reference to the tables above, reference numeral 1 indicates, as a whole, a limiting valve of a fluid flow passing through such a valve.

[0015] Such a limiting valve 1 comprises a support body 2, which extends in a flow plane P transversal (preferably orthogonal) to a direction of transit X of a fluid in a duct 4.

[0016] While the embodiment in figure 7 shows a valve assembly 10 - discussed hereafter - inserted in the fluid duct 4 (the latter only schematised in section) , the limiting valve described herein may be used individually, i.e. separately from a check valve.

[0017] Therefore, in an embodiment not shown of the limiting valve 1, there may be provided sealing means acting between the support body 2 and the fluid duct 4 in order to convey the fluid (for example water) through valve 1 rather than in the space delimited between an outer surface 50 of said body 2 and an inner surface of duct .

[0018] For example, . the support body 2 may delimit externally a recessed seat for the partial housing of said sealing means, in particular a gasket or an O-ring. According to a variant, said seat of the support body 2 may be shaped in a manner similar to the sealing seat 52 of the hollow body 38 shown in figure 9, therefore of a shape generally complementary to an outer surface 66 of the sealing means, of gasket 68 or of the O-ring.

[0019] According to an advantageous embodiment, at least a portion 56 of the outer surface 50 may have a slight frusto-conicity which tapers in the transit direction X of the fluid.

[0020] According to the embodiments shown, the support body 2 comprises a substantially tubular wall 28, which surrounds a body compartment 30. Preferably, a free edge area of said wall 28 delimits the slightly frusto-conical portion 56.

[0021] According to a further variant, the support body 2 comprises a bottom wall 22, which surrounds on the one hand the support body, and which is preferably joined to the tubular wall 28 through a plurality of discrete connection sections 48, for example in the shape of spokes .

[0022] According to a still further variant, in the bottom wall 22 there are formed one or more fluid transit holes 24. [0023] Preferably, the bottom wall 22 is at least partially shaped with a radial pattern. According to a further variant, at least a pair of spokes delimits a fluid transit hole 24.

[0024] The limiting valve 1 further comprises an annular regulation member 6, housed at least partially in the support body 2 and which in conjunction therewith delimits one or more lumina 8 for crossing of said fluid.

[0025] In particular, the annular regulation member 6 is at least partially housed in the body compartment 30, so that the tubular wall 28 at least radially delimits said member 6.

[0026] In the present description, the terms "upstream", "downstream", "radial", and "axial" will be referred to the transit direction of the fluid, unless otherwise specified. In particular, such terms will refer to the transit direction at the inner portion of the fluid within the fluid duct 4, substantially coinciding with the prevailing development axis of such a duct.

[0027] The width of the said lumen 8 is preferably variable and dependent on the flow speed passing through said valve 1. In fact, under the action of the fluid, the annular adjustment member 6 is elastically deformable to narrow said lumen 8 so as to regulate the flow of fluid downstream of valve 1 (and more precisely, downstream of the annular adjustment member) .

[0028] In other words, since a first flow velocity corresponds to a deformation of a certain extent of the adjustment member 6, and thus a given lumen for the transit of the fluid, a higher velocity will correspond to a greater deformation or compression of the member, and a consequently smaller lumen width for the transit of" the fluid.

[0029] Preferably, the annular adjustment member 6 is or includes a gasket or an O-ring. Advantageously, such a member is substantially toroidal in shape, with a section for example circular or elliptical/oval.

[0030] In order to retain the annular adjustment member 6 in the support body 2, the latter preferably comprises a retention pin 26 on which member 6 is mounted, for example in a substantially coaxial manner.

[0031] In the embodiment shown for example in figure 4, the retention pin 26 is at least partially housed inside the body compartment 30, and is therefore at least partially enclosed by the substantially tubular wall 28.

[0032] Preferably, the retention pin 26 extends from the bottom wall 22 in an axial direction, i.e. along the transit direction X.

[0033] According to a further variant, a free end portion 26' of the retention pin 26 branches into ^' a plurality of appendages 36 generally hook-shaped.

[0034] More precisely, appendages 36 extend radially outwardly, so as to prevent an axial disengagement of the annular regulation member 6.

[0035] In fact, the transverse dimensions of the plurality of appendages 36 is superior to a member compartment 58 surrounded by the annular regulation member 6. It follows that, according to this variant, member 6 may be fitted on the retention pin 26 only if the material of which the regulation member 6 is made is elastically pulled, so as to come over said appendages 36 in a direction first radial and then axial.

[0036] The limiting valve further comprises at least a first 12 and a second 14 limiting element on which the annular regulation member 6 works mechanically to determine a first and second limit deformation of said member 6 depending on the flow speed of the fluid.

[0037] In other words, innovatively, the limiting valve object of the present invention allows working in a wider range of flow speeds than the conventional valves, since it uses two different limiters types of the deformation of the regulating member, preferably acting at different times .

[0038] In fact, according to a preferred embodiment, up to a first flow speed, a part 16 of the annular regulation member 6 acts solely on the first limiting element 12, and a different part 18 of the same member acts on the second limiting element 14 above the first speed. For example, part 16 which works first is a lower surface of member 6, while the other part 18 is an outer side surface of such a member.

[0039] It follows that for low flow speed values, the second limiter will remain passive, while upon exceeding the first speed, the two limiting elements will act together.

[0040] According to an embodiment variant, the first 12 and second 14 limiting element, or the plurality thereof, are staggered at least in a radial direction to progressively intercept the annular regulation member 6 in deformation.

[0041] Preferably, the first limiting element 12 comprises one or more containment surfaces 20 delimited by the support body 2 (preferably delimited by the bottom wall 22), wherein the annular regulation member 6 is at least partially housed.

[0042] For example, the containment surface 20 is conformed or has a depth such that, when the annular regulation member is at rest (i.e. in the absence of fluid acting thereon) , less than 50% of its thickness is surrounded by the containment surface 20.

[0043] Advantageously, the limiting valve 1 comprises a single containment surface 20 of a generally truncated- cone or concave shape. Preferably, surface 20 develops annularly around the retention pin 26, when provided.

[0044] According to a further variant, the containment surface 20 extends at a bottom wall 22 of the support body 2, in which at least one fluid transit hole 24 is made communicating with said lumen 8 in a fluidic manner.

[0045] Therefore, according to this variant, the fluid entering into the limiting valve 1 from a body inlet 62 of the support body 2, crosses lumen 8 and comes out therefrom through the fluid transit hole 24 or the plurality, thereof.

[0046] For example, lumen 8 extends annularly within the support body.

[0047] According to a still further variant, the at least one fluid transit hole 24 is arranged radially externally to the retention pin 26 (and in particular outside the containment surface 20), and radially internally of the substantially tubular wall 28.

[0048] According to an advantageous embodiment, the second limiting element 14 comprises at least one radial projection 32 (preferably a plurality of such projections) which extend internally from the tubular wall 28 to intercept the deformations of the annular regulation member 6. [0049] In the embodiment of figure 5, the radial projection is in the shape of a rib arranged parallel to the transit direction. Preferably, there is provided a plurality of radial projections 32, angularly staggered along the tubular wall 28, for example at a constant pitch.

[0050] According to a particularly advantageous embodiment, the containment surface 20 is separated from at least one radial projection 32 by means of a free space 34, inside which space the deformed annular regulation member 6 has radially exceeded the first limiting element 12 but still lies at a distance from the second limiting element 14.

[0051] Therefore, the presence of said free space 34 allows a progressive interception of the annular regulation member.

[0052] The present invention also relates to a valve assembly 10 comprising a check valve 40, which comprises a hollow body 38 housing a mobile obturator 42, and a limiting valve 1, according to any of the previous embodiments, at least partially housed in the hollow body 38.

[0053] Preferably, as for example schematically shown by the arrow in figure 7, the limiting valve 1 is arranged upstream of the check valve 40 in relation to the transit direction X of the fluid.

[0054] Even more preferably, the hollow body 38 internally defines an annular abutment bead 44 for the mobile obturator 42, with which it preferably forms a seal, wherein the bead further delimits a stop surface 46 for the support body 2 of the limiting valve 1.

[0055] Therefore, such a bead carries out the dual function of abutment for both the maximum engagement of the limiting valve ^" 1 in the hollow body 38, and for the mobile obturator 42 when the latter lies in its own interception configuration.

[0056] Referring in particular to the section in figure 8, depending on the flow velocity of the fluid, the mobile obturator can translate between the interception configuration (left), in which the obturator 42 forms a seal with the annular abutment bead 44 - specifically by means of an interposed seal 64 - and a transit configuration (right) in which said obturator 42 is distanced from said bead.

[0057] Advantageously, assembly 10 comprises elastic means 60 acting between the hollow body 38 and the mobile obturator 42 to bring the latter in the interception configuration: when the force of the flow speed on the obturator is then sufficiently high to overcome the force of the elastic means 60, the mobile obturator will arrange in the transit configuration. Conversely, when the force of the elastic means 60 is stronger than the force of the flow on the obturator, the check valve will arrange in the interception configuration, thus preventing the flow in a direction opposite to the transit direction X.

[0058] Advantageously, the valve object of the present invention is constructively simple, therefore suitable to be produced in a cost-effective manner.

[0059] Advantageously, the valve object of the present invention allows creating an interstice with variable section for the crossing of the fluid flow and is designed to prevent a total closure of the same valve.

[0060] Advantageously, the valve object of the present invention is configured to distribute the forces of the fluid in a homogeneous manner along said member, so as to reduce the impact of mechanical stress to which the latter is periodically subjected.

[0061] Advantageously, the assembly object of the present invention is constructively simple since the mobile obturator valve acts directly on the hollow body, the latter also acting as a housing for the limiting valve.

[0062] Advantageously, the assembly object of the present invention is designed to prevent possible leaks of the adjustment member. Furthermore, such a member is also highly localised within the support body.

[0063] A man skilled in the art may make several changes or replacements of elements with other functionally equivalent ones to the embodiments of the above valve and assembly in order to meet specific needs.

[0064] Also such variants are included within the scope of protection as defined by the following claims.

[0065] Moreover, each variant described as belonging to a possible embodiment may be implemented independently of the other variants described.