FR3052221A1 - PRESSURE RELIEF VALVE AND FLUID DISPENSING VALVE COMPRISING SUCH A VALVE - Google Patents

Abstract

Pressure relief valve (1), in particular for a fluid circulation valve, comprising a rod (100) and a guiding means (200), said rod being provided for sliding inside the guiding means, characterized in that the guiding means comprises a first segment (210) forming a guide for the rod, said first segment (210) being extended by a second segment (220), said guide means comprising a flange (230) located at the junction of the first segment ( 210) and the second segment (220), said valve further comprising a resilient means adapted to maintain spaced apart a valve head (110) from the rod (100) and the guide means (200), resting on said collar (230).

Description

The invention relates to a pressure relief valve for a valve in a fluid distribution circuit, particularly for a motor vehicle, and a liquid circulation valve comprising such a valve. The invention finds an application in particular for motor vehicle coolant distribution valves, in particular the ball valves, comprising a device for limiting the pressure within the valve, such as a pressure relief valve. Such a valve is mounted fitted into a housing opening into the valve chamber of the valve, near a side surface of the chamber cooperating with the plug.

According to an earlier solution, it has been developed by the holder a pressure relief valve formed of a set of parts which is supplied preassembled, this set generally comprising: - A valve stem, comprising a valve head, - A guide means of the rod, having a housing inside which the rod can slide, - a biasing means such as a spring, tending to move the valve head of the guide means to press against a valve seat located on a body of the valve.

So that this assembly does not separate, before mounting on the valve, the rod further comprises retaining devices adapted to maintain the rod inside the guide means despite the action of the return means.

We can therefore distinguish three major phases in the life cycle of such a set: - A phase of assembly of this set, which can be extended by phases of packaging, transport ... and finally delivery to the assembly site - A phase of installation in the valve body, - A phase of use.

The function of the guide is to very precisely guide the rod in its sliding so that the valve head is correctly repositioned on its seat after the valve has come into action to prevent leakage. With the current solutions, the guidance is however not satisfactory. The invention aims to solve these problems. For this purpose, it proposes a pressure relief valve, in particular for a fluid circulation valve, comprising a rod and a guide means, said rod being designed to slide inside the guide means, characterized in that the means for guide comprises a first guide segment for the rod.

Through said first segment, the guidance of the rod is improved.

According to features of the invention which can be taken alone or in combination: said first segment has a length greater than the largest dimension of a cross section of the rod, in particular greater than the diameter of the rod, said first segment has a length greater than twice the largest dimension of a cross section of the rod, in particular greater than twice the diameter of the rod. said first segment has a length of about three times the largest dimension of a cross-section of the shank, in particular about three times the diameter of the shank, said first guide segment comprises a first and a second guide portions separate and apart from each other, the wall of the first segment comprises at least one recess located between the first and second guide parts, an inner face of the guide means comprises at least one groove provided for the passage of at least one male retaining member of the rod, a wall portion of the first segment between two grooves having a single recess, the first segment has an opening for the introduction of the rod, the first segment is extended by a second segment; said valve has a first translational guide set between a body of the stem and the first segment and a second clearance between the body and an inner wall of the second segment. ent, the first set being lower than the second set, said second segment is configured to allow a plugging of the valve in a support, in particular within a housing provided for this purpose in said valve, said second segment is configured to to maintain a rod retainer or devices, the guide means comprises a collar which extends radially on its outer face, the collar extends to the junction of the first segment and the second segment, the stem comprises a valve head, the valve further comprises a resilient means able to maintain spaced the valve head and the guide means bearing on said flange, the first segment comprises a plurality of tongues which extend radially and longitudinally to from its outer face and provided to maintain the elastic means. The invention also relates to a fluid distribution valve comprising a pressure relief valve as described above.

Embodiments and variants will be described hereinafter, by way of non-limiting examples, with reference to the accompanying drawings in which:

Figures IA, IB and IC schematically show a general view of the valve, respectively in elevation and in longitudinal section along two positions of the rod,

FIG. 2 represents a valve stem in perspective,

FIGS. 3A and 3B show, in enlarged view, sections of one end of the rod with a pin, respectively according to the prior solution and according to the invention,

FIGS. 4A, 4B and 4C respectively represent a guide means in perspective, a cross section of the guide means and a developed view of the distal opening of the guide means,

FIGS. 5A to 5C respectively represent a developed view of the guide means at the abutment surface in various embodiments,

FIG. 6 represents in perspective another embodiment of a guiding means,

Figure 7 shows in perspective a rod and a guide means having indexing means.

The pressure relief valve 1 according to the invention illustrated in FIGS. 1A, 1B and 1C is an assembly comprising three assembled elements: a rod 100, comprising at a first end a valve head 110 provided with an O-ring 113 at its end; periphery, and at a second end of the male retainers 120 for retaining the rod within a guide means 200, - the guide means or guide 200 within which the rod 100 is slidable; the guide 200 comprises an abutment surface, provided here with internal retaining devices intended to cooperate with the male retaining devices 120 to retain the rod inside the guide means, - A spring 300 tending to move the valve head and the guide means; the spring 300 is omitted from Figures IB and IC.

Initially, these three elements are manufactured separately. They are assembled in the following way: - Slide the spring 300 on the guide 200, - Insert the rod 100 inside the spring 300 and the guide 200 so that the valve head 110 comes to compress the spring 300, - Give an angle of rotation to the rod so that the male retainers 120 engage the abutment surface, particularly with the internal retainers within the guide, - Release the rod 100.

As shown in FIG. 1A, in the assembled valve the spring 300 is energized, aiming to move the valve head 110 and the guide 200 away.

By convention, and regardless of the position of the valve once mounted in the valve, it will be oriented by calling the lower part the part comprising the valve head 110 and the upper part the part comprising the retainers.

These elements will now be described in more detail.

FIG. 2 more particularly illustrates the rod 100. The rod 100 comprises a cylindrical rod body 101 which extends along a longitudinal axis X-X 'whose direction corresponds to the sliding direction of the rod 100 in the 200. The rod body 101 has an outer diameter di and has a guide surface. Said rod 100 comprises at a first end, said lower, the valve head 110 and at a second end, said upper, the male retainers 120 in the form of four lugs 120a, 120b, 120c, 120d (120d not visible) which extend radially and / or coplanar from the surface of the rod body 101. The lugs 120a-120d are distributed at the periphery of the rod body 10 1 so as to delimit equal angles between them, that is, ie with a 90 ° angle between lugs in the case of four lugs as shown in Figure 2.

These lugs are provided to cooperate with an abutment surface 215 of the guides 200 and more particularly here a specific angular portion of said abutment surface 216 forming notches 216 formed on the inner face of the guide 200 so as to maintain the rod 100 to inside the guide 200; these notches will be described later. However, according to the present invention, said abutment surface is not necessarily provided with notches.

Figure 3A illustrates a lug 120a cooperating with a conical abutment surface. This lug is formed of two parallel flat faces 122a, 122b (122b not visible) which extend from the rod body 101 at its upper end and parallel to its axis X-X ', a flat face 121, so-called first bearing face, which extends from the surface of the rod body 101 orthogonal to its axis X-X 'and a curved face 123 which joins the end of the rod and the first bearing face 121. The first bearing face 121 is more particularly intended to cooperate with a second bearing surface of the aforementioned notches of the guide 200. The junctions between the faces of the lugs on the one hand and between the faces of the lugs and the surface of the lugs. the stem on the other hand preferably form rounded.

This solution has the following defect: the disposition of the first support face 121, orthogonal to the axis X-X 'and thus to the rod body 101, is at the origin of significant constraints at the junction of the first face 121 with the body of the rod on the one hand and with the curved face 123 on the other hand when the spring 300 is compressed and under tension. As a result this ergot of the anterior solution is fragile.

FIG. 3B illustrates an advantageous lug 120a: it differs from the anterior solution in that the first bearing face 121a is inclined with respect to the X-X 'axis towards the second end of the rod 100 of a angle α between 30 ° and 60 °, preferably close to 45 °. Combined with a flared abutment surface and more precisely here conical, this arrangement provides the ergot surface support and not more linear and thus better distributes the stresses within the lug 120a which is then less fragile.

In other embodiments: - the lugs are at a number different from four, and their distribution on the stem body may not be equiangular, - the faces 122a, 122b and 121a may not be flat, they may be domed; in particular, the first bearing face 121a can be convexly curved so as to further distribute the stresses, the stop surface then having at least locally, for example at the second bearing surface of the notches 216, a corresponding shape. to allow a surface contact, - the lugs may have different dimensions and not be coplanar, - the rod 100 may extend beyond the lugs 120a - 120d, which are then no longer at the end of the rod 100 .

As illustrated in FIG. 2, the valve head 110 is formed of a flattened body of revolution, comprising a plate 111 below which there is a groove 112 for the O-ring 113. In the direction opposite to this groove, the plate 111 is connected to the rod body 101 by means of a spider 102 having four branches, the faces 102a of these branches which are distant from the rod body 101 being parallel to the axis X-X 'of the rod. When mounting the valve, the base of the spring 300 bears on the valve head being guided by these remote faces 102a.

FIG. 4A illustrates the guiding means 200 of the valve 1. This guiding means extends along a longitudinal axis Y-Y 'which in use will be parallel or coincide with the axis X-X' of the rod It comprises a first segment 210 and, here, a second segment 220, the rod 100 being guided inside the first segment. This arrangement makes it possible to provide a better guidance of the rod 100 compared to the anterior solution that was devoid of such a segment because: it is exercised over a greater guide length of the rod, for example greater than or equal to three diameters of the rod body 101, - it is exerted solely between the rod and the guide, to the exclusion of another element such as the spring.

This gives a better control of the opening and closing of the valve. In particular, the radial tolerance of the installation of the valve head on its seat is decreased.

The second segment 220 has the function, in use, of maintaining the valve 1 within a housing provided for this purpose in the valve body. Its length is greater than or equal to the maximum lift of the valve. For example, it is equivalent to about one stem body diameter.

At the junction between the first and second segments radially extends a flange 230. Tabs 240 extend radially and longitudinally on the outer face of the first segment 210. These tabs 240, as can be seen in FIG. IA, serve to guide or maintain the spring 300.

During the manufacture of the valve 1, the rod 100 must be introduced into the guide 200, more precisely in its first segment 210. For this purpose, the first segment 210 of the guide comprises an axial channel 212 opening on an opening 211 whose The shape corresponds to that of the rod body 101. For the purposes of guiding, the diameter d2 of this channel is substantially equal to the outer diameter di of the rod body 101, or slightly higher. Or the rod has at its second end the male retainers 120 which, as already said, form lugs protruding on the surface of the stem body. In order to allow the crossing of these protruding lugs inside the guide 200, as illustrated in FIG. 4B, the inner surface of the guide comprises grooves 213 intended to allow the passage of the lugs, that is to say that their number their shape, their size and their relative position correspond to those of the lugs. FIG. 4B illustrates an embodiment comprising three tongues 240 for holding the spring and four grooves 213 for passing lugs, but of course these numbers could be different, for example three tongues and three grooves, the grooves then being arranged radially in the extension of the tabs, as shown in Figure 6.

As illustrated in FIG. 4C, the internal surface of the channel 212 is divided longitudinally into longitudinal sliding portions 214a -214d; it comprises as many grooves 213 and sliding portions as there are pins, the rod 100 sliding on these sliding portions for its guidance within the guide 200.

FIG. 6 illustrates another embodiment of the guiding means 200. This comprises recesses 250 in the wall of the first segment 210, which extend longitudinally from the collar 230 to the vicinity of the opening 211 of the 212. Each recess is located between two tongues 240 and the grooves 213 are located radially in the extension of the tongues. The guide of the rod 100 in the guide means 200 is therefore exerted from two distinct and remote portions 210a, 210b of the guide means 200, a first portion 210a located in the vicinity of the opening 211 of the channel 212, a second portion 210b located in the vicinity of the flange 230, shorter than the first segment. The advantage over a first fully cylindrical guide segment 210 as shown in FIG. 4A is that it is no longer necessary to provide a clearance angle for the channel 112, without losing the guiding quality of the channel 112. rod 100. When molding the guide means, different pins can be used to obtain the recesses 250.

FIGS. 5A to 5C illustrate internal retaining means of the guide 200. In these figures is represented the insertion direction I of the rod 100.

The channel 212 of the guide 200 includes a narrowing, preferably located at the flange 230, to provide engagement means to the male retainers 120 of the shank 100 through the abutment surface 215 which forms here a shoulder within said channel. FIG. 5A illustrates a first exemplary embodiment. The narrowing takes the form of a plane radial flange, on which the grooves 213 open. When the rod 100 is inserted into the guide 200, the male retainers 120 slide in the grooves, projecting beyond the rim 215, and then the operator provides an angle of rotation to the rod and release, so that the male retainers 120 abut on the rim 215 and thus lock the rod within the guide. A disadvantage of this exemplary embodiment is that the operator has no way of checking whether the male retainers are properly resting on the rim 215, i.e., away from the opening of a groove 213. It may happen that the retaining devices 120 are unstably engaged on the rim 215, and that the valve 1 disengages for example under the effect of vibrations during transport or when it is placed in the body. Valve.

In the valve of more advantageous embodiments, as illustrated in FIG. 5B, the rim 215 has a notch 216 between two groove outlets 213. In this way, when the operator places the rod 100 in the guide 200 , it can perceive by hand, by a notching effect, the moment when the lugs 120a-120b penetrate into the notches 216. Each notch comprises two axial and parallel walls, a bottom and the second bearing face 216a, intended for receive a first bearing surface 121, 121a of a lug 120a - 120d. In this embodiment, the second bearing face 216a of the notches is flat and extends along a radius.

Figure 5C illustrates another embodiment of the internal retainers. In this embodiment, the radial flange 215 is not plane but comprises corrugations in the axial direction, so as to present in developed, measured in the direction of introduction I, extrema, including maxima or "bumps" 215a and minimums 215b or "troughs". By maximum 215a is meant that this portion of the rim is the farthest from the opening 211 of the guide 200; by minimum 215b is meant that this portion of the flange is closest to the opening 211. The trace of the radial flange on the inner face of the guide means is a closed curve which has minimums and maximums measured in the direction of introduction of the stem.

In Figure 5C, this trace takes the appearance of a sinusoid, but other forms are covered by the invention as sawtooth for example.

The internal face of the guide means always comprises the grooves 213, provided for the passage of the lugs 120a - 120b during the introduction of the rod into the guide 200. These grooves open on the rim 215 at a "hump" 215a. In this way, the operator no longer has to give an angle of rotation to the rod 100 once introduced into the guide 200, the lugs are directed to a "hollow" 215b along the slope of the rim 215, this of as much as the rod is returned by the spring 300. In this embodiment of the rim 215, a notch is not necessary to achieve the desired notching effect, the lugs are in a stable position at the bottom of a " hollow ". If for more security notches 216 are provided, they are advantageously located in a respective "hollow".

As illustrated in FIG. 5C, the second bearing face 216b of the notches 216 is inclined to cooperate with the first inclined bearing face 121a of a lug 120a-120d of FIG. 3B. This second bearing surface 216b is angularly offset with respect to the Y-Y 'axis of the guide 200 towards the opening 211 of the first segment 210 of the guide 200.

Each second bearing face 216b may be flat to cooperate with a first bearing surface 121a flat, or concave if the first bearing face 121a is convex.

In addition, the valve comprises means capable of facilitating its assembly. Indeed, at rest the spring 300 is relatively long, so that the second end of the rod 100 is out of the guide means, which does not allow a pre-centering of the rod in the guide before compression of the spring .

Thus, in order to facilitate the introduction of the rod 100 into the channel 212, each groove 213 comprises, at the opening 211 of the channel 212, a flared entry 213a, as can be seen in FIG. 4C in which I represents the direction of insertion of the stem. The surfaces 213b of these flares may take a curved shape, as shown in FIG. 4C, or be planar or comprise facets (not shown). This arrangement makes it possible to make up for an angular indexing defect, for example up to 15 °. Other indexing means are provided, usable by the assembly tooling of the valve, which will now be described.

As shown in FIG. 7, the valve head 110 has two indexing tabs 131 having radial and longitudinal components disposed on the face of the valve head opposite to the rod body 101. In the example shown, these indexing tabs are arranged symmetrically with respect to the axis X-X 'of the rod and facing one another, in a cavity 132 formed in this face of the valve head.

Alternatively or cumulatively, the flange 230, preferably located at the junction of the first 210 and the second 220 guide segment comprises one or more notches 231, at its periphery, here two arranged in axial symmetry. The invention is not limited by the foregoing description: the first indexing means such as the tabs 131 could be arranged at the periphery of the valve head, they could take the form of a recessed impression. instead of tongues, - they could not be arranged in a cavity, - the second indexing means such that the notches could take the form of pins or tabs, - they could be arranged on the first segment (210) or the second segment (220) of the guide, the first and second indexing means could be present in a different number of two. The invention also relates to a valve equipped with such a valve.

Said valve, not shown, may comprise a cylindrical body defining a housing accommodating a plug movable in rotation along a longitudinal axis of said housing. Said body has inlet / outlet orifices communicating with said housing, for example or axial inlet orifice and a plurality of lateral orifices, in particular radial, located on a lateral wall of the body. By way of example, a first outlet orifice is intended to communicate with a cooling channel of a cooling circuit of a motor vehicle engine, a second outlet orifice is intended to communicate with a heating channel of the passenger compartment of the vehicle and a third output port is for communicating with a short circuit path. The valve is configured so that the angular position of the plug determines the opening / closing of the outlets.

The valve may be mounted mounted in a lumen communicating with the housing defined by the valve body, at its side wall, so as to put said housing in communication with one of the above mentioned channels, including when the corresponding outlet port is closed by the bushel ..

Claims (9)

claims 1. Pressure relief valve (1) in particular for a fluid circulation valve, comprising a rod (100) and a guide means (200), said rod being provided for sliding inside the guide means, characterized in that the guide means comprises a first segment (210) forming a guide for the rod, said first segment (210) being extended by a second segment (220), said guide means comprising a flange (230) located at the junction of the first segment (210) and the second segment (220), said valve further comprising resilient means for keeping a valve head (110) apart from the rod (100) and the guide means (200), resting on said flange (230). 2. Pressure relief valve according to claim 1, characterized in that said first segment (210) has a length greater than the largest dimension of a cross section of the rod. 3. Pressure relief valve according to claim 1, characterized in that said first segment (210) has a length greater than twice the largest dimension of a cross section of the rod. 4. Pressure relief valve according to claim 1, characterized in that said first segment (210) has a length of about three times the largest dimension of a cross section of the rod. 5. Pressure relief valve according to any one of the preceding claims, characterized in that said first guide segment comprises first and second guide portions (210a, 210b) separate and remote from each other. 6. Pressure relief valve according to claim 5, characterized in that the wall of the first segment (210) has at least one recess (250) between the first and the second guide portions (210a, 210b). 7. Pressure relief valve according to claim 6, characterized in that an inner face of the guide means (200) comprises at least one groove (213) provided for the passage of at least one male retaining member of the rod ( 120), a wall portion of the first segment (210) between two grooves having a single recess (250). 8. Pressure relief valve according to any one of the preceding claims, characterized in that the first segment (210) has an opening (211) for the introduction of the rod (100). 9. A fluid dispensing valve having a pressure relief valve according to any one of the preceding claims.