Faucet with spherical rotating closure

A faucet including: a body having an axis channel; a spherical rotating closure mounted pivotable in the body, between a closed position and an open position, the closure including a through orifice allowing the passage of a fluid from an upstream pipe to a downstream pipe, in open position; an upstream seat having a central passage, mounted in the channel of the body upstream of the closure so as to be mobile in translation along the axis and urged towards the closure by elastic means; a protuberance provided in the upstream seat projecting towards the closure, and a recess provided on the closure, to co-operate with the protuberance in closed position of the closure; and means for equalizing the pressure between upstream and downstream of the upstream seat, prior to the faucet being opened.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a valve with a spherical rotating plug.

BRIEF DISCUSSION OF RELATED ART

Such a valve conventionally comprises a body in which a channel is formed, and also a spherical plug which, mounted in the body such that it can pivot about an axis perpendicular to the axis of the channel, has a through orifice allowing the passage of fluid between an upstream pipe and a downstream pipe, in the open position. Furthermore, an upstream seat is generally mounted in the channel of the body, upstream of the plug, such that it can move translationally along the axis of the channel of the body. The upstream seat is intended to ensure that the valve is leaktight in the closed position, by being pressed against the plug.

On the one hand, valves used at high pressures are known, as illustrated in documents FR 2 564 558 and FR 2 646 488. In that case, most of the bearing force of the upstream seat against the plug results from the pressure exerted by the fluid upstream. To prevent the plug engaging frictionally against the upstream seat when rotating the plug, and thus to make it easier to open the valve, these documents provide means for equalizing the pressure on either side of the upstream seat, prior to the valve being opened. Furthermore, the valves described in these documents may include springs which tend to move the upstream seat away from the plug. The force of these springs is countered by the high pressure of the fluid when the valve is in the closed and leaktight position, but after the pressures between the upstream end and the downstream end of the upstream seat have been equalized, these springs allow a retreating movement of the upstream seat with respect to the plug.

However, these valves are not suited for uses at low or medium pressures since, in that case, the pressing action of the upstream seat against the plug, resulting from the upstream pipe pressure alone, is insufficient to ensure satisfactory leaktightness of the valve in the closed position. The provision of this leaktightness is also impeded by the presence of the springs which tend to move the upstream seat away from the plug.

On the other had, valves used at low or medium pressures are known. In such a valve, illustrated for example in document JP 01 015575, it is necessary to provide elastic means which urge the upstream seat toward the plug and press it against the latter, so as to provide satisfactory leaktightness in the absence of a sufficient fluid pressure upstream. On opening, the upstream seat remains pressed against the plug by the elastic means. Document JP 01 015575 makes provision to equip the upstream seat with rollers cooperating with recesses formed in the plug. Consequently, the friction between the upstream seat and the plug is limited, and the valve can be opened more easily as a result. In this way the valve is prevented from jamming, or even from being damaged.

However, the valve proposed by document JP 01 015575 would not be able to operate at high pressures. Specifically, in that case, the force exerted by the upstream fluid would be so high that the pressing action of the upstream seat against the plug would prevent the plug from turning, this being so even with rollers having been provided.

BRIEF SUMMARY OF THE INVENTION

The present invention aims to overcome the drawbacks mentioned above by providing a valve which can be used throughout the whole range of pressures (low, medium and high pressures) and which has improved leaktightness, while at the same time being easy to operate without the risk of jamming.

Accordingly, the invention relates to a valve comprising:a body in which there is formed a channel with an axis and which is intended to be placed between an upstream pipe and a downstream pipe;a substantially spherical rotating plug mounted in the body such that it can pivot about an axis substantially perpendicular to the axis of the channel, between a closed position and an open position, the plug having a through orifice with an axis that is intended to allow the passage of fluid from the upstream pipe to the downstream pipe in the open position;an upstream seat having a central passage and mounted in the channel of the body upstream of the plug such that it can move translationally along the axis of the channel of the body;elastic means designed to urge the upstream seat toward the plug;at least one projection formed on the upstream seat and projecting substantially parallel to the axis of the channel of the body in the direction of the plug, and at least one first recess formed in the plug and designed to cooperate with the projection when the plug is in the closed position; and additionally comprising means for equalizing the fluid pressure between the upstream end and the downstream end of the upstream seat, prior to the valve being opened.

Thus, in the closed position, the upstream seat is in its most downstream position since the projection is housed in the recess. Leaktightness is ensured by the action of the elastic means and by the pressure of the upstream fluid (the relative size of these two forces depending on the pressure at which the valve is used), which tend to press the upstream seat against the plug.

When the plug is pivoted toward its open position, first of all the pressures between the upstream end and the downstream end of the seat are equalized. Thus, the force needed to press the upstream seat against the plug now results only from the force of the elastic means. When the pivoting of the plug is continued, the projection leaves the recess, causing the upstream seat to retreat with respect to the plug, that is to say to be moved upstream. Consequently, the friction between the upstream seat and the plug is very limited and the valve can be opened more easily as a result.

The projection may be formed by a roller rotatably mounted about an axis embodied by a pin secured to the upstream seat and substantially parallel to the pivoting axis of the plug, and/or be formed on a ring fastened to the downstream part of the upstream seat such that it is substantially centered on the axis of the channel of the body. In a variant, the upstream seat itself forms a ring.

Advantageously, the plug comprises a second recess situated substantially at the same distance as the first recess from the plane which is orthogonal to the pivoting axis of the plug and which passes through the axis of the through orifice, said second recess being designed to cooperate with the projection when the plug is in the open position. Thus, in the open position, the upstream seat is in its most downstream position since the projection is housed in the recess.

According to one possible embodiment, the plug has at least two assemblies each comprising a first recess or first and second recesses, the two assemblies being substantially symmetrical to one another with respect to the plane which is orthogonal to the pivoting axis of the plug and which passes through the axis of the through orifice, and the upstream seat has two projections which are substantially symmetrical with respect to the axis of the channel of the body and situated along a line substantially parallel to the pivoting axis of the plug, such that each projection can cooperate with the recess or recesses of one of the two assemblies. This symmetrical arrangement makes it possible for the upstream seat to retreat parallel to the axis of the channel of the body while preventing the upstream seat from being set “crossways” in this channel, which could result in the occurrence of friction on the plug as this plug is being pivoted.

Furthermore, the plug may comprise at least two assemblies each comprising a first recess or first and second recesses, the two assemblies being substantially symmetrical to one another with respect to the pivoting axis of the plug. This makes it possible to obtain a “bidirectional” valve, the recesses of one assembly cooperating with a projection formed on the downstream seat.

The plug may thus comprise four assemblies consisting of one or two recesses each (on the upstream side/on the downstream side and on either side of the axis of the channel of the body). Advantageously, the upstream seat comprises a plurality of successive annular portions from the upstream end toward the downstream end, the dimensions of which are chosen such that, owing to the fluid pressure upstream and downstream of the upstream seat:when the pressure-equalizing means are in the closed position, the upstream seat is pressed against the plug, thus ensuring that the valve is leaktight;when the pressure-equalizing means are in the open position, a thrust force counter to the elastic means is exerted on the upstream seat.

The means for equalizing the fluid pressure between the upstream end and the downstream end of the upstream seat comprise, for example:an upstream annular chamber whose downstream wall is formed by a shoulder formed on the upstream seat and facing upstream, and a downstream annular chamber situated between the upstream seat and the plug, not communicating with the central passage of the upstream seat when the valve is in the closed and leaktight position;a duct that is formed in the body and has a first portion connected to the upstream annular chamber by a channel and a second portion in communication with the downstream annular chamber;means for obstructing the passage between the first and second portions of the duct, which means are housed in said duct and can move translationally along the axis of the duct, said obstruction means being urged toward the closure position of said passage by elastic means and having a bearing face which, in the closure position of said passage, is situated outside the duct, in the region of the second portion thereof;a cam which, formed on the body between said obstruction means and a spindle which actuates the pivoting movement of the plug and is substantially coaxial with the pivoting axis of said plug, is able, when said actuating spindle is rotated, to cooperate with the bearing face and thus cause the obstruction means to move in the duct, counter to the force exerted by the elastic means and the pressure, toward a position of releasing the passage between the first and second portions of the duct.

According to one possible embodiment, the axis of the duct is substantially orthogonal to the pivoting axis of the plug, and the cam comprises a part situated opposite the bearing face of the obstruction means, a first end of which is fastened to the body of the valve (or to the cap secured to the body) such that it can pivot about an axis substantially parallel to the pivoting axis of the plug, and a second end of which has a projection projecting toward the actuating spindle of the plug, said projection being designed to cooperate, when the valve is in the closed and leaktight position, with a cavity formed in the actuating spindle.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1represents a valve1comprising a body2in which there is formed a channel with an axis3. The body2is intended to be connected to an upstream pipe by means of an upstream flange4and to a downstream pipe by means of a downstream flange5. The fluid conveyed by the pipes flows in the direction indicated by the arrow F, the terms “upstream” and “downstream” being defined with respect to this direction.

Other body variants are possible, particularly a version in which the body is directly connected to the upstream and downstream pipes without the use of flanges. The internal elements are then mounted and demounted from the top of the body.

The valve1also comprises a rotating plug6mounted in the body2, via bearings7,8, such that it can pivot about an axis9substantially perpendicular to the axis3. The plug6features a main spherical part having a cylindrical through orifice10with an axis11, the axis11being situated in the plane which is orthogonal to the pivoting axis9of the plug6and which passes through the axis3of the channel of the body2. The main spherical part of the plug6is extended by two cylindrical parts12whose axis is substantially coincident with the pivoting axis9of the plug6, each extending on one side of the main spherical part.

The plug6is assigned an actuating spindle13, substantially coaxial with the pivoting axis9, which passes through the body2via interposed gland packings14. The actuating spindle13is extended by an external lever (not shown) which allows a user to move the plug6between:an open position, in which the axis11of the orifice10and the axis3of the channel of the body are substantially coincident, the fluid then being able to flow from upstream to downstream;and a closed position, in which the axis11of the orifice10forms an angle α of around 70° to 80°, for example 80°, with the axis3of the channel of the body. Of course, the plug6is dimensioned so that, in this position, the fluid cannot pass from upstream to downstream.

In each of the cylindrical parts12extending the main spherical part of the plug6are formed four substantially identical recesses situated substantially at the same distance from the plane which is orthogonal to the pivoting axis9of the plug6and which passes through the axis11of the through orifice10:a first recess55offset angularly from the axis11of the through orifice10by an angle α of around 70° to 80°, for example 80°, in a direction such that, when the plug6is in the closed position, the first recess55is oriented in the upstream direction;a second recess56situated substantially in the plane formed by the pivoting axis9of the plug6and the axis11of the through orifice10;a third recess57substantially symmetrical to the first recess55with respect to the pivoting axis9of the plug6; anda fourth recess58substantially symmetrical to the second recess56with respect to the pivoting axis9of the plug6.

The recesses have, for example, a semicylindrical shape whose axis is substantially parallel to the pivoting axis9of the plug6. Moreover, the four recesses formed in one of the cylindrical parts12and the four recesses formed in the other of the cylindrical parts12are substantially symmetrical to one another with respect to the plane which is orthogonal to the pivoting axis9of the plug6and which passes through the axis11of the through orifice10of the plug6.

An upstream seat15having a central passage16is mounted substantially coaxially in the channel of the body2, upstream of the plug6, such that it can move translationally along the axis3to a limited extent.

From upstream to downstream, the upstream seat15has a first annular portion17, a second annular portion18of larger outside diameter, defining a stop surface, a third annular portion19of even larger outside diameter, and then a fourth annular portion20whose outside diameter is smaller than that of the third annular portion19. These four annular portions substantially have the same inside diameter, such that the central passage16is substantially cylindrical.

The upstream seat15finally has, most downstream, a fifth annular portion59(defining the sealing surface of the upstream seat15), the outside diameter of which is smaller than the outside diameter of the third annular portion19(and here substantially equal to the outside diameter of the fourth annular portion20), and the inside diameter of which is larger than the outside diameter of the first annular portion17. The advantage in selecting these dimensions is explained below.

The upstream seat15is mounted in the body2by means of an annular guide element21, placed between the third annular portion19and the body2, and an annular closure element22placed between the first annular portion17and the body2. Seals23,24are interposed between the body2and the guide element21and between the body2and the closure element22, respectively. Furthermore, rings25are placed between the closure element22and the upstream seat15, a slight radial clearance being formed between these two parts.

Between the closure element22, the guide element21and the upstream seat15is defined an upstream annular chamber26which is in limited fluid communication with the central passage16of the upstream seat15via the rings25and the radial clearance mentioned above. In the upstream annular chamber26is placed a spring washer27bearing, on the one hand, on the stop surface formed between the first and second annular portions17,18of the upstream seat15and, on the other hand, on a stop surface formed on the closure element22. The washer27thus urges the upstream seat15toward the plug6, the effect of which is to press the downstream end28of the upstream seat15against the plug6and, consequently, ensure that the valve1is leaktight when the plug6is in the closed position. A metal diaphragm54is, furthermore, arranged in the upstream annular chamber26against the downstream face of this chamber, one end of the diaphragm54being fastened to the guide element21and the other end being fastened to the upstream seat15. The diaphragm54provides leaktightness between the upstream seat15and the body2when the valve is in the closed and leaktight position.

A ring29is mounted on the fourth annular portion20of the upstream seat15, in the channel of the body2. The ring29, illustrated inFIG. 2, comprises two diametrically opposed, substantially parallelepipedal housings30in each of which is mounted a roller31such that it can rotate about a common axis32substantially joining the centers of the two housings30. The ring29is mounted on the upstream seat15such that the axis32is substantially parallel to the pivoting axis9of the plug6and intersects the axis3of the channel of the body2. The rollers31are thus arranged each opposite a cylindrical part12of the plug6, at the same axial level as the recesses55,56,57,58, and project toward the plug6with respect to the downstream end28of the upstream seat15.

Furthermore, a false downstream seat33having a central passage34is mounted inside the channel of the body2, on the downstream side of the plug6, with an interposed seal35in order to provide continuity between the central passage16, the orifice10and the central passage34. In a variant, the false downstream seat33could have a similar structure to the upstream seat15, in particular for using the valve1in both directions of fluid flow (direction of the arrow F and opposite direction). In the case of a bidirectional valve, each of the two “upstream” and “downstream” seats is preferably equipped, in addition to the diaphragm54, with a counter-diaphragm which comes into play, during the equalizing phases, to protect the diaphragm associated with the seat on the “downstream” side against the reverse pressure effect, which could not be borne by a single diaphragm.

When the valve1is in the open position, the upstream fluid flow path, the central passage16of the upstream seat15, the through orifice10of the plug6, the central passage34of the false downstream seat33and the downstream fluid flow path are substantially coaxial and have similar cross sections.

Finally, as illustrated inFIGS. 1 and 3, the valve1comprises means for equalizing the pressure between the upstream end and the downstream end of the upstream seat15, prior to the valve1being opened, these means forming a bypass circuit.

The equalizing means comprise first of all a cylindrical duct36, with an axis37, formed in the body2substantially orthogonally to the pivoting axis9of the plug6and to the axis3of the channel of the body2. The duct36comprises a first portion38having radial orifices39opening into a channel40which is drilled obliquely in the body2starting from the upstream annular chamber26. The duct36also comprises a second portion41which extends the first portion38in the direction of the actuating spindle13and whose diameter is smaller than that of the first portion38. The second portion41has radial orifices42opening into the central volume accommodating the plug6, this volume forming, when the valve1is in the closed and leaktight position, a downstream annular chamber43situated between the upstream seat15and the plug6and not communicating with the central passage16of the upstream seat15.

Arranged substantially axially inside the duct36is a push rod44comprising a ball45whose diameter is sufficient to be able to obstruct the passage between the first portion38and the second portion41at the point where the cross section narrows. The push rod44is extended, beyond the ball45, up to its free end, which forms a bearing face46situated opposite the actuating spindle13. A spring47is mounted in the duct36, around the push rod44. The push rod44can move translationally along the axis37between:a closure position, toward which the push rod44is urged by the spring47. In this closure position, the ball45obstructs the passage between the first portion38and the second portion41of the duct36, the fluid then not being able to pass from the upstream annular chamber26to the downstream annular chamber43. Furthermore, the push rod44projects from the duct36in the region of the actuating spindle13, the bearing face46hence being situated outside the duct36;and a release position, in which the push rod44is moved away from the actuating spindle13. The spring47is then compressed and the bearing face46is in the vicinity of that end of the second portion41facing the actuating spindle13. In this position, the passage between the first portion38and the second portion41of the duct36is no longer obstructed by the ball45, the upstream26and downstream43annular chambers thus being in fluid communication.

The pressure-equalizing means comprise, moreover, a cam48formed by a curved part connected to the cap60, itself fastened to the body2of the valve1, the convex outer face49of which cam is arranged opposite the bearing face46of the push rod44. The cam48comprises a first end which is fastened to the cap60such that it can rotate about an axis50substantially parallel to the pivoting axis9of the plug6, and a second end to which there is fastened a roller51such that it can rotate about an axis52substantially parallel to the axis50. The roller51is designed to cooperate, when the valve1is in the closed and leaktight position, with a cavity53formed in the actuating spindle13. The cavity53is angularly separated from the axis37of the duct36by an angle β of around 20°.

When the valve1is in the closed and leaktight position (FIGS. 4a,4b,4c), the plug6is arranged such that the axis11of its through orifice10forms an angle α of around 80° with the axis3of the channel of the body2. The roller31of the ring29is then housed in the first recess55formed in the plug6(FIG. 4). Thus, owing to the action of the washer27and the pressure upstream, the upstream seat15is pressed against the plug6and the distance d between the upstream face of the closure element22and the upstream face of the upstream seat is at a maximum (FIG. 4b). The fact that the outside diameter of the fifth annular portion59of the upstream seat15is smaller than the outside diameter of the third annular portion19makes it possible to render the valve1leaktight by a pressure-sealing effect when the bypass is closed. Moreover, the roller51of the cam48is housed in the actuating spindle13of the plug6and the push rod44is in the closure position (FIG. 4a).

When a user acts on the lever, he causes the actuating spindle13to pivot about the axis9. The start of the pivoting movement of the actuating spindle13(pivoting of approximately 10° to 20°) does not result in any pivoting of the plug6, on account of the play. The plug6hence remains in the closed position, as inFIG. 4c. However, the consequence of this pivoting is that the roller51of the cam48exits the cavity53(FIG. 5). The cam48thus pivots about the axis50, causing the push rod44to move away from the actuating spindle13, thereby releasing the passage between the first and second portions38,41of the duct36. The fluid can then pass from the upstream annular chamber26to the downstream annular chamber43. There is thus equalization of the pressures on either side of the upstream seat15via the bypass circuit. The upstream seat15is thus now pushed toward the plug6only by the action of the washer27. The valve1is in the pressure-equalizing position, and the plug6is still in the closed position. However, because the inside diameter of the fifth annular portion59of the upstream seat15is larger than the outside diameter of the first annular portion17, there is a force opposing the force exerted by the washer27, the effect of which is to reduce, or even eliminate, the action of this washer27and hence reduce the friction during the opening of the valve1.

Further pivoting movement of the lever, and hence of the actuating spindle13, causes the plug6to pivot, while the thrust force exerted by the upstream seat15owing to the upstream pressure has been eliminated. When the plug6pivots about the axis9, the roller31of the ring29leaves the first recess55so as to roll against the lateral face of the cylindrical portion12of the plug6. This is followed by a retreating movement of the upstream seat15with respect to the axis9, against the force exerted by the washer27. The distance d between the upstream face of the closure element22and the upstream face of the upstream seat is then minimal. The pivoting of the plug6is thus facilitated through the fact that the friction against the upstream seat15is largely reduced, since this friction is located only at the roller31and not over the whole contact area between the upstream seat15and the spherical part of the plug6. The valve1is in the intermediate open position (FIGS. 6a,6b,6c).

In the open position (FIGS. 7a,7b,7c), the roller31of the ring29is housed in the second recess56, the upstream seat15thus being once again advanced toward the plug6and pressed against it (maximum distance d). The angle of rotation of the plug6is limited to a value of between 70° and 80° such that the total rotation of the lever remains 90°: thus, the invention can be used with standard actuators (pneumatic, electric or hydraulic actuators). The bypass circuit for its part is still open.

When the actuating spindle13is operated in the direction of closure, first of all the play is taken up and then the plug6is rotated about the axis9, the bypass circuit still being open. When the plug6returns to the completely closed position, simultaneously with the end of rotation of the actuating spindle13, the roller31of the ring29comes to be housed in the first recess55(maximum distance d) and the roller51of the cam48comes to be housed in the cavity53. The push rod44, under the effect of the spring47, moves translationally toward the actuating spindle13. The ball45then closes off the passage between the upstream annular chamber26and the downstream annular chamber43. The pressure difference between the upstream end and the downstream end of the upstream seat15then contributes to pressing the latter against the plug6.

Thus, the invention brings a decisive improvement over the prior art by providing a valve which is perfectly leaktight at low or medium pressure and which is easy to operate.

It goes without saying that the invention is not limited to the embodiment described above by way of example but that, on the contrary, it covers all the variant embodiments thereof.