FR2937394A1 - ROTARY SHUTTER VALVE - Google Patents

Abstract

The invention relates to a valve provided with a rotary-type flap. The valve (1) comprises a body (2) delimiting an internal chamber (7) having a surface portion (12) provided with at least one opening (13, 14) corresponding to a channel of this valve (1), and a flap (16; 16 ') movably mounted along this surface portion (12), said flap (16; 16') having a screen (17; 17 ') running along the surface portion (12) for sealing the opening (13, 14) or leaving it open as a function of the position of this flap (16; 16 ') about the axis (AX), this flap being provided with a sealing segment (22; 22') mobile in a normal direction on the screen (17; 17 '). The invention applies to three-way valves used in thermal engines such as diesel engines, supercharged engines and engines in which is ensured recirculation of exhaust gas.

Description

The invention relates to a valve for equipping a heat engine such as a supercharged engine and / or exhaust gas recirculation.

BACKGROUND OF THE INVENTION Such a valve can be used, for example to measure the proportion of exhaust gas reinjected into the engine when it is of the recirculating gas type. It can also be used to dose the amount of air to be cooled before admission to a supercharged engine. Such a valve may have two lanes, three lanes, four lanes or more, which depends mainly on the use that is made of it.

In a supercharged engine, the outside air is compressed by a compressor before being admitted into an engine inlet manifold. A radiator and a bypass are interposed between the compressor and the inlet manifold, to cool or not to cool the compressed air before admission into the engine. The compressor is thus connected to an inlet of a three-way distribution valve, having a first output connected to the radiator, and a second output connected to the branch. The bypass and the radiator outlet meet in an intake line in the manifold. The valve has two butterflies located respectively in the first and the second outlet, which are controlled to direct the air to either the radiator or to the bypass, depending on whether or not it must be cooled before admission. These butterflies can be controlled either by two independent actuators or by a single actuator via a mechanism comprising a gear set by which this actuator is connected to each butterfly. 2 When the first throttle is fully-green while the second throttle is fully closed, air from the compressor is directed to the radiator for cooling before admission. Conversely, when the second throttle is fully open while the first throttle is closed, air is admitted to the engine without being cooled, which typically corresponds to a regeneration phase of a particulate filter fitted to this engine.

OBJECT OF THE INVENTION The object of the invention is to propose a solution for reducing the manufacturing cost of such a valve. SUMMARY OF THE INVENTION To this end, the subject of the invention is a valve comprising a body delimiting an internal chamber pre-feeling a surface portion provided with at least one opening corresponding to a channel of this valve, and a mounted flap. movable along this surface portion, this flap having a screen along the portion of the surface to close the opening or leave open depending on the position of the flap about the axis, this flap being provided with a sealing segment movable in a normal direction on the screen.

The invention also relates to a valve as defined above, in which the portion of the surface in which the opening opens out, has a shape of cylindrical portion of axis, and wherein the flap is rotatably mounted around the axis of this cylindrical portion. The invention also relates to a valve as defined above, wherein the sealing segment is a rigid segment having a shape corresponding to the contour of the screen, in which this segment is engaged in a corresponding throat of the screen and in which elastic means are interposed between the segment and the screen to press the segment on the cylindrical portion. The invention also relates to a valve as defined above, in which each elastic element is a spring engaged in a housing formed by a hole locally deepening the groove. The invention also relates to a valve as defined above, in which each elastic element is a cylindrical stud of elastomer-type material engaged in a housing formed by a widening hole and locally deepening the groove. The invention also relates to a valve as defined above, in which the elastic means are formed by an elastomer seal of the same general shape as the segment, this seal being interposed between the segment and the bottom of the groove. The invention also relates to a valve as defined above, in which each cylindrical stud is an integral part of the elastomer seal. The invention also relates to a valve as defined above, in which the elastomer seal is overmoulded on one face of the segment. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a perspective view of the valve according to the invention; Figure 2 is a perspective view of the shutter of the valve according to a first embodiment of the invention; Figure 3 is another partial perspective view of the shutter of the valve according to the first embodiment of the invention; Figure 4 is a partial perspective view in section of the shutter of the valve according to the first embodiment of the invention; Fig. 5 is a perspective view showing a portion of the valve flap according to the second embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION As seen in FIG. 2, the three-way valve 1 according to the invention comprises a valve body 2 carrying three ducts marked by 3, 4 and 6. The valve body 2 delimits an internal chamber 7. having an inner face formed of three parts. The first generally flat part marked by 8 has an opening 9 through which it communicates with the pipe 3, and the second part 11, generally flat extends perpendicular to the first part. The third portion 12, in the form of a quarter-cylinder axis AX has two openings 13 and 14 communicating respectively with the lines 4 and 6. The lines 3 and 4 are aligned with each other, while the duct 6 is inclined at about sixty degrees with respect to the duct 4, and at about one hundred twenty degrees relative to the duct 4, when the body 2 is seen from above, that is to say parallel to the axis AX. In operation, the valve body 2 which has its upper part open in FIG. 2 is closed by a lid or cover, not shown, to close this chamber hermetically. This three-way valve comprises a flap marked 16 which is mounted rotatable about the axis AX, being installed inside the chamber 7. When this flap occupies a first angular position, as in Figure 2, it closes the opening 13 to prevent entry into the valve. This flap 16 may also be placed in a second angular position, in which it closes the opening 14 so as to oppose entry into the air valve. from the pipe 6. As shown in Figure 1, the pipes 2 and 3 are oriented along axes whose intersection is on the axis AX, so as to spontaneously balance the forces applied to the shutter when closing an opening through which circulates a gas under ession. The shutter 16 can be placed in any intermediate position between the first and the second position, to partially close off the openings 13 and 14, so as to proportion the air from the one and the other of these openings, which is introduced into the valve body and discharged via the opening 9, that is to say the pipe 3.

As can be seen in FIG. 3, this flap comprises a screen 17 in the form of a cylindrical portion of axis AX cylinder, of substantially rectangular contour, carried by an upper flat flange 18 having a rectangular contour extending in a direction normal to the axis AX, and by a lower flange marked by 19 in Figure 4, but having the same shape and the same orientation. The free end of the upper flange is for-view of a hole 21 of hexagonal section, coinciding with the axis AX, as well as the free end of the lower flange. A sleeve or axle with hexagonal section, not shown, and driven by an actuator, such as an electric motor of torque motor type, rigidly secured to the valve body is engaged in these holes to move the flap from the first position to the second and vice versa. The screen 17 of the flap 16 carries a sealing member which is interposed between this screen and the wall in the form of a cylinder portion 12, while being held in abutment on this wall by elastic elements interposed between the body sealing and screen.

This sealing member is a segment 22 constituted by a rigid frame having a shape corresponding to the contour of the screen 17 but slightly smaller dimensions than those of this contour.

In other words, this segment 22 has a general shape corresponding to the projection of a rectangle on a cylindrical portion. It thus comprises two rectilinear edges 23 and 24 parallel to each other, as well as an upper curved edge and a lower curved edge parallel to one another, and marked respectively by 26 and 27. The upper edges and lower have curvatures corresponding to arcs of the same radius as the cylindrical wall 12. Similarly, the outline of the screen 17 is delimited by two straight edges 28 and 29, and by an upper edge and a lower edge in arcs marked respectively by 31 and 32. This screen 17 has a main face or wall 33 in the form of a cylindrical portion, provided with a peripheral rib 34, forming a bead, which protrudes radially relative to the axis AX of this main face 33. The peripheral rib 34 has a shape corresponding to the letter U, and it runs along the rectilinear edges 28 and 29 of the screen 17 as well as its upper curved edge 31. The segment 22 is held in a groove 36 who e The segment 22 thus has its curved upper edge 26 in the base of the U, and its two straight edges 28 and 29 engaged in the branches of the U. As seen in FIG. 2, the curved lower edge 27 of the segment 22 is free since it is neither held nor guided by the groove 36. This solution reduces the risk of jamming of the segment in the groove 36 in case of establishment a differential thermal expansion between the screen and the segment. In the example of FIGS. 2 to 4, the segment 22 is kept pressed to the inner face of the cylindrical wall 12 of the valve body 2 by four coil springs marked 38, 39, 41 and 42, to ensure the tightness when the shutter closes an opening. These springs are engaged in corresponding holes forming housing. Each of these holes is made in the groove 36, which widens it locally, extending beyond the bottom thereof, these holes being oriented in a direction normal to the plane defined by the two straight edges 28 and 29 of the screen. As can be seen in FIG. 2, these springs are situated at the ends of the upper and lower curved edges 26 and 27 of the segment 22. Additionally, the segment 22 comprises four pins identified by 43, 44, 46 and 47, having diameters substantially identical to those of the helical springs, and by which this segment is supported on these springs. In the examples of the figures. Each peg is integrated with the curved edge that carries it, so that it locally constitutes a widening-ment of this edge whose cross section is rectangular, as that of the groove 36. The segment 22 is thus movable in translation in the groove 36, in a direction normal to the plane defined by the rectilinear edges 28 and 29, while being held pressed against the wall 12 by the springs, which ensures a sealed application of the screen 17 on this wall to hermetically closing the opening of this wall in front of which is placed the flap 16. According to another embodiment shown in Figure 5, the segment is pressed against the cylindrical wall by an elastomeric seal interposed between the segment and the bottom throat. In this other embodiment, the flap and the segment which it carries, marked respectively by 16 'and by 22', have the same shapes as in the embodiment of FIGS. 2 to 4, except as regards the section cross section of the groove in which the segment is engaged. As regards this second embodiment, the flap 16 'and the segment 22', as well as their parts, bear the same numerical references as in the example of FIGS. 2 to 4, supplemented by the prime sign. Thus, the segment 22 'here also has a general shape of rectangle projected on a cylindrical portion, each of its edges has a rectangular cross section, and it comprises four pins located at each end of its two curved edges. Complementarily, the screen 17 'also has a groove 36' into which this segment engages, this groove 36 'being again provided with holes widening it locally and extending beyond its bottom, the pieces of the segment sliding in these holes. The elastomer seal which is indicated by 48 'in FIG. 5 is overmoulded on the rear face of this segment 22', which is the face of this segment located opposite the bottom of the groove 36 '. This seal extends the segment 22 'in a direction normal to the plane defined by the two straight sides of this segment, having a shape very close to that of this segment 22'. Its thickness, measured radially relative to the axis AX, is smaller than that of the segment over most of its contour, and it also comprises studs located in the extension of the pieces of the segment, these studs. on the contrary having a thickness greater than that of the pions. Each pad of the elastomeric seal 48 'is engaged in a corresponding housing to form an elastic member plating the segment 22' to the wall, similar to the springs of the first embodiment. One of these pads is visible in Figure 5 being identified by 49 '. On the other hand, the groove 36 'has a cross section which comprises a U-shaped main part, as in the first embodiment, but a groove is formed at the bottom of this main part, of smaller width than the latter, to receive the elastomer seal 48 '.

As seen in Figure 5, the width of the joint, which is measured parallel to the axis AX for its curved edges, is identical to that of the segment 22 ', and corresponds to the width of the groove made at the bottom of the groove. The elastomer seal is thus engaged so as to seal in the groove of the groove 36 ', and moreover, it is overmolded on the rear face of the segment, to constitute a sealed barrier preventing gas from bypassing the segment by the bottom of the throat. The invention provides the following advantages in particular. With the single flap, the architecture of the three-way valve is significantly simplified only one internal chamber is needed instead of two to contain a single flap instead of two. In addition, the control mechanism of the valve is reduced to a minimum since a single torque motor driving an axis of rotation of the flap is sufficient to drive the valve, directly and without the need for gears.

Finally, the presence of the rigid segment held in abutment on the internal cylindrical surface of the valve body makes it possible to ensure a high degree of tightness making it possible to integrate this valve with a heat engine. It can be integrated in a supercharging system, exhaust gas recirculation, or other application in which the valve is traversed by a gas under pressure and must be able to oppose the passage of this gas.

Claims (8)

REVENDICATIONS1. Valve (1) comprising a body (2) delimiting an internal chamber (7) (2) having a surface portion (12) provided with at least one opening (13, 14) corresponding to a channel of this valve (1) , and a flap (16; 16 ') mounted movably along this surface portion (12), this flap (16; 16') having a screen (17 17 ') running along the surface portion (12) for closing the opening (13, 14) or leaving it open as a function of the position of this flap (16; 16 ') around the axis (AX), this flap being provided with a sealing segment (22 22 ') moving in a normal direction on the screen (17 17'). 2. Valve according to claim 1, wherein the surface portion (12) in which opens the opening (13, 14), has a cylindrical portion shape axis (AX), and wherein the flap (16; 16 ') is rotatable about the axis (AX) of this cylindrical portion (12). A valve according to claim 2, wherein the sealing segment is a rigid segment (22; 22 ') having a shape corresponding to the contour of the screen (17-17'), wherein said segment (22; 22 ') ) is engaged in a corresponding groove (36; 36 ') of the screen (17 17'), and in which elastic means (43, 44, 46, 47) are interposed between the segment (22; 22 ') and the screen (17; 17 ') for pressing the segment (22; 22') on the cylindrical portion (12). 4. Valve according to claim 3, wherein each elastic element is a spring (43, 44, 46, 47) engaged in a housing formed by a hole locally deepening the groove (36). 5. Valve according to claim 3, wherein each resilient means is a cylindrical stud made of elastomer-type material (49 ') engaged in a housing formed by a widening hole and locally deepening the groove (36'). 6. Valve according to claim 3, wherein the elastic means are formed by an elastomer seal (48 ') of the same general shape as the segment (22'), this seal being interposed between the segment and the bottom of the throat (36 '). Valve according to claims 5 and 6, wherein each cylindrical stud (49 ') is integral with the elastomeric seal (48'). Valve according to claim 6 or 7, wherein the elastomeric seal (48 ') is overmoulded on one face of the segment (22').