Valve with compensating element and compensating element for a valve

Abstract

A valve (1) for controlling the flow of a fluid, comprising: a valve body having at least one first body portion (2) formed of a molded plastic material; a chamber (6) for the passage of a fluid defined in the first body portion (2) and having at least one fluid inlet (6a) and at least one fluid outlet (6b); a valve seat (7) defined in the chamber (6) for the passage of the fluid; means (8-9) for blocking the fluid, displaceable relative to the valve seat (7) to control the flow of the fluid; and a valve body for controlling the volume and / or volume of the fluid. and a compensation element pre-positioned to compensate for a possible increase in pressure, the compensation element having a compensation body (26) made of an elastically deformable and / or elastically compressible material, the molded plastic material of the first body part (2) being harder than the elastically deformable and / or elastically compressible material, the first body part (2) defining a tubular part (23) extending between a valve seat (7) and one of an inlet (6a) and an outlet (6b) in a chamber (6) for the passage of a fluid, the compensation body (26) being mounted in the chamber (6) for the passage of a fluid so as to at least partially surround the tubular part (23).

Description

[Technical Field]

[0001] The present invention relates to valves for controlling the flow of fluids, and has been developed with particular reference to electrically operated valves installed in fluid circuits, systems or devices, particularly in motor vehicles or household appliances. [Background technology]

[0002] Valves for controlling the flow of fluids have been known for a long time and are sold for use in a wide range of fields. It is also known to provide compensation elements in valves of the above type in order to compensate for possible increases in the volume and / or pressure of the controlled fluid and to prevent the occurrence of structural damage that could impair the operation of the valve itself. Solutions of this type are typically employed in hydraulic and fluid systems that operate at low ambient temperatures for more or less long periods, such as in automobiles, in household appliances installed outdoors (e.g., on residential balconies), or in irrigation systems.

[0003] For example, U.S. Patent No. 7,891,370 describes an irrigation pilot valve having a body made of a plastic material. The valve includes a solenoid housing with a core provided with an elastomeric opening / closing element that can cooperate with a valve seat. To prevent possible structural damage due to freezing of the controlled liquid, the valve is provided with a tubular compensation element made of an elastomeric material and therefore elastically deformable or compressible. Such a compensation element is attached to a housing intentionally defined in the valve body. This housing is separate from the chamber in which the valve seat is located, but is in fluid communication with said chamber. In this way, the increase in volume caused by freezing of the fluid (usually water) can be compensated for within the valve body by elastic compression of the compensation element.

[0004] Although effective, the solutions described in this document are relatively complex, cumbersome, and costly to the point of being impractical. Therefore, there is a need for a valve for controlling fluid flow that does not suffer from these drawbacks. Summary of the Invention

[0005] In view of the above, the object of the present invention is to provide a valve for controlling the flow of a fluid, which valve has structural features that make it easier and more efficient to use than the known solutions mentioned above.

[0006] In this summary, according to one aspect, it is an object of the present invention to provide a valve having a simple, cheap and compact structure, with a compensation element suitable for preventing damage that may occur due to an increase in the volume and / or pressure of the fluid. According to another aspect, it is an object of the present invention to provide a valve that prevents the risk of malfunction due to inefficient cooperation between the means for blocking the fluid and the corresponding valve seat. According to yet another aspect, it is an object of the present invention to provide a valve that is easy and cheap to manufacture.

[0007] According to the present invention, one or more of the above-mentioned objects, as well as other objects that will be specified below, are achieved by a valve for controlling the flow of a fluid and a corresponding compensation element having the features set out in the appended claims, which form an integral part of the technical teachings provided herein in relation to the invention.

[0008] Further objects, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, given purely by way of non-limiting example, in which: [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic perspective view of a valve according to a possible embodiment of the present invention; [Figure 2] 1 is a schematic exploded view of a valve according to a possible embodiment of the present invention; [Figure 3] 1 is a schematic cross-sectional view of a valve according to a possible embodiment of the invention, with the corresponding means for blocking the fluid in the closed position; [Figure 4] 1 is a schematic cross-sectional view of a valve according to a possible embodiment of the invention, with the corresponding means for blocking the fluid in the open position; [Figure 5] 1 is a schematic perspective cross-sectional view of a valve according to a possible embodiment of the invention, with the corresponding means for blocking the fluid in the closed position; [Figure 6] 1 is a schematic perspective cross-sectional view of a valve according to a possible embodiment of the invention, with the corresponding means for blocking the fluid in the closed position; [Figure 7] 1 is a schematic perspective view of a compensation element in a possible embodiment of the present invention; [Figure 8] 1 is a schematic perspective view of a compensation element in a possible embodiment of the present invention; [Figure 9] 1 is a schematic perspective cross-sectional view of a portion made of molded plastic material of a body of a valve according to a possible embodiment of the invention, without a corresponding compensating element attached thereto; [Figure 10] 1 is a schematic perspective cross-sectional view of a portion made of molded plastic material of the body of a valve according to a possible embodiment of the invention, with a corresponding compensation element mounted thereon; FIG. [Figure 11] 5 is a cross-sectional view similar to FIG. 4 for illustrating the operation of the compensation element provided by the present invention. [Figure 12] 1 is a schematic cross-sectional view of a portion of a valve to illustrate the deformations that a tubular portion of the valve body may undergo due to freezing of the controlled fluid in the absence of a compensation element. [Figure 13] 1 is a schematic cross-sectional view of a portion of a valve to illustrate the deformations that a tubular portion of the valve body may undergo due to freezing of the controlled fluid in the absence of a compensation element. [Figure 14]1 is a schematic cross-sectional view of a portion of a valve to illustrate the deformations that a tubular portion of the valve body may undergo due to freezing of the controlled fluid in the absence of a compensation element. [Figure 15] 15 is a schematic view similar to FIGS. 12 to 14 of a valve according to an embodiment of the present invention. FIG. [Figure 16] 4 is a schematic cross-sectional view similar to FIG. 3, but of a possible variant embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] The reference to "one embodiment" or "one embodiment" in the text of this specification is intended to indicate that a particular configuration, structure, or feature described in connection with an embodiment is included in at least one embodiment. Therefore, the appearance of phrases such as "in one embodiment," "in one embodiment," and "various embodiments" in various places in this specification do not necessarily refer to the same embodiment. Furthermore, specific conformations, structures, or features defined in the text of this specification may be combined in any suitable manner in one or more embodiments, even if different from those shown. Reference numbers and spatial designations (such as "top," "bottom," "top," "bottom," "upward," "below," etc.) used in this specification are provided merely for convenience and do not define the scope of protection or the scope of the embodiments. In this specification and the appended claims, the general term "material" is understood to include mixtures, compositions, or combinations of multiple different materials (e.g., multilayer structures or composite materials). In the figures, the same reference numbers are used to refer to elements that are similar (similar) to each other or technically equivalent to each other.

[0011] In the accompanying drawings, elastically deformable elements such as gaskets and opening / closing members are shown in an undeformed state in some drawings (e.g., Figures 3 to 6, 11, and 16) for the sake of illustration.

[0012] Referring initially to Figure 1, a valve for controlling fluid flow according to a possible embodiment of the present invention is generally designated by the reference numeral 1. In various embodiments, valve 1 is an electrically actuated (motorized) valve, particularly a solenoid valve.

[0013] The valve 1 comprises a valve body 2. At least a portion of the valve body 2 is formed from a molded plastic material, such as a thermoplastic material, for example, polyamide, polypropylene, polyphenylene sulfide, or polyphthalamide, which may optionally be filled and may include reinforcing materials, for example, glass fibers.

[0014] In the illustrated embodiment, the valve body 2 is formed entirely of molded plastic material, although this feature is not to be understood in a limiting sense. In other embodiments, the valve body 2 may include one or more portions formed of one or more different materials, such as metal, in addition to portions formed of molded plastic material.

[0015] 2-4, in various embodiments, the plastic material of the valve body 2 is overmolded onto a metal insert, which here has the shape of a plate 3. In other embodiments, the insert or plate 3 may be mounted on or engaged with the body 2. Preferably, the metal plate 3 has a substantially square cross-section, although this feature is not limiting. In other embodiments (not shown), the plate 3 may have a different cross-section, for example, a rectangular or circular cross-section.

[0016] In various embodiments as shown in Figures 2 to 4, the plate 3 is partially englobed or embedded in the plastic material in the first end region 2' of the valve body 2. At least a part of the insert or plate 3 that is not embedded in the plastic material of the valve body 2, i.e. that protrudes from the valve body 2, may be configured as a polarization element for the purpose of mounting the valve on another device. The insert or plate 3 may also serve other purposes, if necessary, for example to provide a fixing element such as a flange with a hole for a screw or a relief belonging to a bayonet coupling.

[0017] As will be described below, in various embodiments, the plate 3 is part of the electromagnetic yoke of the actuation coil of the valve 1 .

[0018] The provision of an insert such as plate 3 is also particularly advantageous for the purpose of fixing an electrical-actuation assembly, described below, to valve body 2. For this purpose, plate 3 preferably has one or more grooves 4 on one or more of its peripheral surfaces that protrude outward from the material forming valve body 2. The function of grooves 4 will be explicitly explained below. In the illustrated embodiment, plate 3 has at least one groove 4 on each of its two opposing sides, although this feature is not to be understood in a limiting sense.

[0019] With particular reference to FIG. 2 , the valve body 2 defines a seat 2 a (see also FIGS. 9-10 ). The seat 2 a is adapted to receive a corresponding annular sealing element 5, such as an X-ring type gasket as illustrated, or a gasket with a flat surface (e.g., a square or rectangular cross section). In the illustrated example, the seat 2 a is located in the first end region 2′ of the valve body 2, at the portion of the valve body 2 that protrudes axially beyond the plate 3, i.e., at the proximal end of the valve body 2. Preferably, the annular element 5 and the seat 2 a have a substantially circular shape. However, it will be understood that in other embodiments (not shown), the seat 2 a and the annular element 5 may be absent or may have shapes and dimensions different from those shown in FIG. 2 .

[0020] As shown particularly in Figures 3-4, the valve body 2 comprises a chamber for the passage of a fluid, designated by reference numeral 6, defined within a portion formed from a molded plastic material. The chamber is bounded by a generally cylindrical peripheral wall 2b. The peripheral wall 2b has an inner surface 6' that bounds the periphery of the chamber 6.

[0021] Chamber 6 includes at least one fluid inlet and at least one fluid outlet. In the illustrated embodiment, chamber 6 includes only one inlet 6a and only one outlet 6b, the relative arrangement of which will be explained in more detail later in this specification. However, in other embodiments (not shown), chamber 6 may have two or more fluid inlets and / or two or more fluid outlets. In various embodiments, inlet 6a is defined at the axial end of valve body 2, opposite a through-hole surrounded by seat 2a for gasket 5, while outlet 6b is defined in peripheral wall 2b.

[0022] Within the chamber 6 for the passage of fluid there is defined a valve seat, for example shown by the reference numeral 7 in Figure 3. Shut-off means 8, 9 displaceable relative to the valve seat 7 are adapted to cooperate with this valve seat to control the flow of fluid. In a preferred embodiment, the shut-off means 8, 9 are displaceable relative to the valve seat 7 at least between a closed position (shown in Figure 3) in which fluid cannot pass from the inlet 6a to the outlet 6b, and an open position (shown in Figure 4) in which fluid can pass from the inlet 6a to the outlet 6b, in particular a maximum open position in which fluid can pass at a maximum flow rate or velocity.

[0023] In a preferred embodiment, valve 1 is a valve of the open / closed type (either normally closed or normally open), i.e., the shut-off means 8, 9 can only assume two positions, the open and closed positions described above. However, in other embodiments (not shown), the shut-off means 8, 9 and corresponding actuation assemblies are configured to allow the shut-off means 8, 9 to be displaced relative to the valve seat 7 between one or more intermediate positions relative to the open and closed positions shown in Figures 3 and 4. This allows for variably controlled flow rates of fluid between the inlet 6a and outlet 6b of chamber 6.

[0024] In a preferred embodiment, the fluid shutoff means 8, 9 comprises a valve member 8 (or valve element), preferably at least partially formed of an elastically deformable material, such as an elastomeric material. In the illustrated example, the valve member 8 is essentially configured as a rubber element or tip, particularly a substantially cylindrical element. The valve member 8 is fixed to one axial end of a corresponding drive shaft, as described below. Here, the drive shaft is formed by a movable core 9 of a solenoid. It is understood that the valve member 8 may have different shapes and dimensions in different embodiments and may have different hardnesses (e.g., hardnesses between 50 and 80 ShA) depending on the application. In some cases, the valve member 8 may be formed of metal and / or have a shape designed to facilitate variable flow or volume control as described above.

[0025] 4 to 6, in the closed position of the valve 1 (FIG. 3), when the opening / closing member 8 is on the valve seat 7, fluid circulation between the inlet 6a and the outlet 6b of the chamber 6 is prevented. In this type of embodiment, the cross-sectional dimensions of the opening / closing member 8 are preferably larger than the cross-sectional dimensions of the valve seat 7.

[0026] However, in other embodiments (not shown), the opening and closing member 8 may be configured to at least partially penetrate into the central passage of the valve seat 7, for example, when the opening and closing member is brought into the corresponding closed position and / or intermediate adjustment position. Thus, in these embodiments, the cross-sectional dimensions of the opening and closing member 8 may be at least partially smaller than the cross-sectional dimensions of the valve seat 7. The penetration depth of the opening and closing member 8 into the valve seat may vary in different embodiments.

[0027] Returning to FIG. 2 , as previously mentioned, in various embodiments, the opening / closing member 8 is associated with the end of a drive shaft or core 9. The drive shaft or core 9 preferably has a substantially circular cross-section. The core 9 can be displaced away from or toward the valve seat 7 by an appropriate actuation assembly. In various embodiments, the actuation assembly of the valve 1 includes an electric actuator. In the preferred embodiment shown, the electric actuator is a solenoid, generally designated 10 in FIGS. 3 and 4 . The solenoid has windings 11 including electrical wire wound around a bobbin 12. The bobbin 12 is axially traversed by a cavity (not shown). The core 9 is slidably engaged in at least a portion of the cavity. At least a portion of the core 9 is formed of a material that can be attracted by a magnetic field, i.e., a ferromagnetic material. The cavity of the bobbin 12 has a diameter slightly larger than that of the core 9 to allow the core to slide. For this purpose, at least the part of the chamber 6 in which the head portion of the core 9 slides, and which is provided with the opening and closing member 8, has a circular cross section with a diameter that corresponds substantially to the diameter of the cavity of the bobbin 12.

[0028] The solenoid 10 is preferably protected by a corresponding housing (casing) 13. The housing 13 is preferably an overmolded housing made of an electrically insulating material, preferably a molded plastic material such as polyamide, polypropylene, polyphenylene sulfide, or polyphthalamide, possibly of the type containing a filler material.

[0029] Housing 13 preferably has a generally cylindrical outer shape (see FIG. 2) and, in various embodiments, similarly defines a radially projecting connector body, designated 15. In other embodiments (not shown), the connector body may extend in the same axial direction as the actuation coil (i.e., the same as the assembly formed by bobbin 12 and winding 11).

[0030] The housing 13 defines a seat at its top, designated 13a in Figure 2, for receiving a corresponding annular element 14, preferably an X-ring type gasket or other gasket having a flat surface. Preferably, the seat 13a and the corresponding annular element 14 have a substantially circular shape. However, it will be understood that in other embodiments (not shown), the seat 13a and the annular element 14 may be absent or may have different shapes and dimensions.

[0031] In the illustrated embodiment, the solenoid 10 can be connected to a mains power supply by means of a connector body 15. Within the connector body 15, at least two electrical terminals 16 (only one of which is shown in the various figures) are arranged, one for each end of the electrical wire of the winding 11 wound on the bobbin 12. In accordance with known techniques, an electric current is passed through the winding 11 to generate a magnetic field, which causes the core 9 to be axially displaced within the cavity of the bobbin 12, preferably against the action of a resilient element such as a spring. In this way, by electrically supplying the solenoid 10, the core 9 can be displaced relative to its resting position, e.g., the position in which the hydraulic ducts 6 a, 6 b are closed (in this position, the opening / closing member 8 is held in a position corresponding to the valve seat 7, preferably pressed against the valve seat 7 by the action of the aforementioned resilient element). The resulting displacement of the core 9 results in a displacement of the opening and closing member 8 relative to the valve seat 7, thereby allowing fluid flow between the inlet 6a and outlet 6b of the chamber 6.

[0032] 2-6, in various embodiments, the core 9 defines a blind cavity 9a, preferably having a cylindrical portion (notch), at the end opposite the opening / closing member 8. The cavity 9a is prearranged so that a first end 17' of the spring 17 rests on the bottom of the cavity 9a, while an opposite end 17'' of the spring 17 rests on a counter core portion generally designated 18.

[0033] The counter core part 18 is typically made of a ferromagnetic material and has a portion 18' with a substantially circular cross section. This portion is adapted to be fixedly inserted into a corresponding portion of the cavity of the bobbin 12. In the illustrated example, the counter core part 18 further has an enlarged head portion, designated 18'', whose outer circumferential dimension is preferably larger than the through cavity of the bobbin 12. Preferably, the transition region between the portions 18' and 18'' of the counter core part 18 defines a seat or shoulder 18a for accommodating an annular sealing element 20, such as an O-ring type gasket, as partly shown in FIG. 2 . More preferably, the peripheral surface of the portion 18' is provided with teeth or reliefs 18b. The teeth or reliefs 18b mechanically cooperate with the surfaces defining the axial cavity of the bobbin (see, for example, Figures 3-4) and essentially act as a wedge to block portion 18' of counter core portion 18 within bobbin 12 through mechanical interference.

[0034] In the illustrated embodiment, the portion 18' of the counter core 18 does not have any cavity at the contact surface with the second end 17'' of the spring 17. However, in other embodiments (not shown), the second end 17'' of the spring 17 can rest on the bottom of a blind cavity defined in the portion 18' opposite the head portion 18''.

[0035] The actuator assembly, including the solenoid 10 and housing 13, is fixed to the region 2' of the valve body 2 so that the head region of the core 9 (with the opening and closing member 8 associated with it) protrudes from the assembly itself into the chamber 6, as can be clearly seen in Figures 3-4. In this case, a sealing means represented by a gasket 5 operates between the front portions of the assemblies 10-13 and the valve body 2.

[0036] 1-6, in various embodiments, the housing 13 having the solenoid 10 therein is mechanically secured to the valve body 2 by a metal armature 21, particularly formed of a ferromagnetic material. Here, the metal armature 21 is substantially U-shaped, i.e., having two generally parallel upright walls 21a connected by a transverse portion 21b.

[0037] The end of wall 21a opposite wall 21b may be provided with appendages 22 configured to engage with the grooves 4 (see FIG. 2) of plate 3. For example, an extension of each appendage 22 may be engaged in a respective one of grooves 4. The terminal extensions of the same appendages 22 may be bent to engage plate 3 and armature 21 together, thereby completing the electromagnetic yoke of solenoid 10. In this example, the assembly consisting of solenoid 10 and housing 13 is thus packed between valve body 2 and armature 21, with gasket 5 disposed therebetween.

[0038] In the various embodiments as shown, the armature 21 has a hole 21' in the lateral wall 21b, which allows the portion 18' of the counter-core part 18 to penetrate into the cavity of the bobbin 12 up to the end of its mechanical travel, determined by the head portion 18'', with the possible sealing element 20 resting on an internal shoulder of the cavity of the bobbin 12. Preferably, in the assembled configuration, the armature 21 and the counter-core part 18 are in contact, for example with mutual mechanical interference, i.e. are coupled at an electromagnetic level.

[0039] According to one important aspect, the valve body 2 made of plastic material is molded to define a longitudinally extending tubular portion that extends within a chamber for the passage of fluid between the valve seat and one of the fluid inlet and outlet. Preferably, the tubular portion extends longitudinally or axially between the valve seat and at least one of the inlet and outlet in the same direction as the movement of the valve opening / closing means. More preferably, the other of the fluid inlet and outlet is disposed transversely to the tubular portion.

[0040] With reference to the illustrated example, and as shown in particular in Figures 3-6 and 9-10, the valve body 2 defines a tubular portion, designated by reference numeral 23, which here extends within the chamber 6 between the valve seat 7 and the fluid inlet 6a, preferably substantially coaxially with respect to the cylindrical circumferential surface 6' of the chamber 6 itself. Preferably, the tubular portion is substantially cylindrical in shape.

[0041] In a preferred embodiment of the present invention, the average thickness of the tubular portion 23 is smaller than the average thickness of the wall 2b of the valve body 2 which defines the periphery of the chamber 6 for the passage of a fluid (the average thickness of the tubular portion 23 means the average between the minimum and maximum thickness of the wall of the portion 23, and the average thickness of the wall 2b means the average between the minimum and maximum thickness of the wall 2b).

[0042] Molded plastic materials typically undergo what is known as "shrinkage" after the molding process. This shrinkage is essentially a reduction in the material's dimensions as it cools and hardens. This shrinkage varies depending on the type of material (whose properties may vary to some extent depending on the raw material manufacturer) and on other process parameters. These process parameters can vary due to a wide range of factors (e.g., ambient and / or mold temperature, wear, molding speed, etc.). As a result of this shrinkage, in the case of valves of the type considered here, the valve seat changes in size relative to its optimal design dimensions, which can cause the opening / closing member 8 and the valve seat 7 to operate incorrectly. This can result in incorrect control of fluid flow by the valve.

[0043] To overcome this drawback, in a preferred embodiment of the present invention, the same molded plastic material as the material of the valve body 2 is used to define a thin tubular portion 23, which defines the valve seat 7 at its end. As already mentioned, the average thickness of the tubular wall is smaller than the average thickness of the wall 2b that defines (divides) the periphery of the chamber 6. By way of example, the average thickness of the wall of the tubular portion 23 may be between 1.6 and 1.8 mm, and the average thickness of the peripheral wall 2b may be between 2.5 and 2.8 mm.

[0044] In this manner, considering that the shrinkage of the plastic material after the molding process is substantially proportional to the thickness of the material itself, shrinkage of the tubular portion 23 is significantly suppressed, allowing a sufficiently precise definition of the valve seat 7 in any case, i.e., so as not to impair cooperation with the opening / closing member 8. Meanwhile, the peripheral wall 2b of the valve body 2 defining the chamber 6 can be formed with a thickness that is deemed most suitable, taking into account the operating pressure of the fluid to be controlled and the mechanical anchorage of the actuator assemblies 10-13. It will be further understood that the valve seat 7 may also be directly defined by the tubular portion 23 itself. That is, the valve seat 7 is made integral with the valve body 2, eliminating the need for an additional element dedicated for this purpose, as in, for example, U.S. Pat. No. 7,891,370.

[0045] As mentioned above, preferably, the fluid inlet and fluid outlet not defined by tubular portion 23 are disposed transversely relative to tubular portion 23. As a result, (with reference to the non-limiting example shown in the figures, in which tubular portion 23 extends between valve seat 7 and fluid inlet 6a) fluid outlet 6b is defined in wall 2b of valve body 2 transversely relative to tubular portion 23. It will be appreciated that in other embodiments, the port designated by reference numeral 6a in the figures may correspond to the fluid outlet, and the port designated by reference numeral 6b may correspond to the fluid inlet. In such embodiments, as a result, tubular portion 23 extends between valve seat 7 and the fluid outlet, and the fluid inlet is disposed transversely relative to tubular portion 23. In other embodiments, port 6b may also be disposed substantially parallel to port 6a. For this purpose, body portion 2 may have an appropriate shape.

[0046] As mentioned above, in the preferred embodiment shown in the figures, the tubular portion 23 has a substantially cylindrical shape, i.e. a circular cross section, however, this characteristic should not be understood in a limiting sense, as other cross-sectional shapes are also possible, particularly in relation to the type of closure member 8 used.

[0047] According to one aspect of the present invention, the valve 1 includes a compensating element prearranged to compensate for potential increases in the volume and / or pressure of the controlled fluid. The compensating element is mounted within the chamber 6. As shown, for example, in FIGS. 2 and 7-8, the compensating element is generally designated by the reference numeral 25 and has at least one compensating body 26 made of an elastically deformable and / or elastically compressible material, such as an elastomeric material. For example, the body 26 may be molded from a silicone material, such as a silicone elastomer, liquid silicone rubber (LSR), or fluoroliquid silicone rubber (FLSR). Preferably, the compensating body 26 is made of an impermeable material to prevent fluid from penetrating into the compensating body 26. For this purpose, the selected material preferably has a closed-cell structure. The molded plastic material of the valve body 2 is in any case stiffer than the elastically deformable and / or elastically compressible material of the compensating body 26 .

[0048] In the illustrated embodiment, the entire compensating element 25 is constituted by the compensating body 26 made of a deformable and / or compressible material. However, this feature should not be understood in a limiting sense, and in other embodiments (not shown), the compensating element 25 may include other parts made of different materials. For example, the compensating element may include a core made of a relatively hard material onto which the compensating body 26 is fixed (e.g., overmolded). As can be seen, for example, in Figures 2-3, the body 26 of the compensating element 25 is constructed as a separate part relative to the valve body 2 and is designed to be mounted on the valve body 2.

[0049] As shown in particular in Figures 9-10, the compensating body 26 is mounted in the chamber 6 so as to at least partially surround the tubular portion 23. For this purpose, the compensating body 26 preferably has a cross-section of a suitable shape, in particular a substantially cylindrical peripheral wall 27. However, this feature is not limiting and in other embodiments (not shown) the compensating body 26 may have a cross-section of a shape different from cylindrical.

[0050] Preferably, the compensating element 25 has at least one peripheral surface having a profile that is at least partially complementary to the profile of the peripheral surface of one of the chamber 6 and the tubular portion 23. For example, the outer surface of the peripheral wall 27 of the compensating body 26 may have a profile that is at least partially complementary to the surface 6' of the body 2 that defines the periphery of the chamber 6. Additionally or alternatively, the inner surface of the peripheral wall 27 may have a profile that is at least partially complementary to the outer surface of the tubular portion 23.

[0051] On the other hand, in a possible variant embodiment, the compensating element 25 is connected, for example elastically, only to the tubular portion 23, leaving a space (for example an annular gap) relative to the surface 6' that laterally delimits the chamber 6. Alternatively, the compensating element 25 can be connected to the peripheral surface 6' of the chamber 6 via reliefs or protrusions on the outer surface of the wall 27. These reliefs or protrusions may extend in the axial direction of the element 25.

[0052] Preferably, the axial extension of the compensating body 26 is such that, when placed in the chamber 6, the upper end of the compensating body 26 is located above the valve seat 7, as can be seen, for example, in Figure 3. In any case, the body 26 is axially hollow, so that the opening / closing member 8 carried by the core 9 can reach the valve seat 7.

[0053] 7, in various embodiments, the compensating body 26 has at least one lateral passage 28 in the peripheral wall 27 of the compensating body 26 to allow the passage of fluid between the valve seat 7 and the outlet 6b. Preferably, the lateral passage 28 comprises a recess extending from the first longitudinal end 31 of the wall 27.

[0054] The shape and extension length of the passage 28 may vary from embodiment to embodiment. In the illustrated embodiment, the compensating body 26 has only one lateral passage 28. However, in other embodiments (not shown), two or more lateral passages 28 may be provided. This solution is required, for example, when the chamber 6 for the passage of fluid has two or more outlets (or inlets) 6b.

[0055] In the illustrated embodiment, the transverse passage 28 comprises (consists of) a recess extending from the first longitudinal end 31. However, in other embodiments (not shown), the passage 28 can have other shapes, for example, a shape formed by a hole provided in the peripheral wall 27 or another hole provided in the compensating body 26.

[0056] In various embodiments, the valve body defines a polarization or positioning element within the chamber for the passage of fluid, which cooperates with a polarization or positioning counter-element of the compensation element, for example during assembly, to ensure the correct mutual angular position of the valve body and the compensation element. Preferably, the polarization element is defined in a position transverse to the tubular portion defining the valve seat.

[0057] For example, and with particular reference to Figures 4 and 9, a polarization element 30 is defined within chamber 6. Polarization element 30 is here substantially constituted by a rib or relief on the peripheral surface 6' of chamber 6 and extends at a position transverse to tubular portion 23.

[0058] 8, the peripheral wall 27 of the compensation body defines a polarization counter element 29, which is pre-positioned to receive the element 30. In this example, the polarization counter element 29 consists of a recess extending from the second longitudinal end 32 of the cylindrical wall 27 of the compensation body 26. Also in this case, the shape and extension (extension length) of the recess may vary from embodiment to embodiment.

[0059] In a preferred version, the polarization counter-element or recess 29 has opposing inclined surfaces intended to mate with the surfaces of the polarization element or relief 30, which are also preferably at least partially inclined in opposite directions. The inclination of these surfaces is also advantageous for autonomous polarization or centering during installation, in particular via a slight autonomous rotation of the compensation body 26 until it is oriented in a preset position.

[0060] The provision of the element 30 and the counter-element 29 not only simplifies the assembly of the valve 1, but also prevents rotation of the compensating body 26 relative to the valve body 2. Thus, the lateral passage 28 is always optimally positioned to allow the passage of fluid between the valve seat 7 and the outlet (or inlet) 6b.

[0061] In the illustrated embodiment, the compensation body 26 has only one polarization counter-element 29, but it is clear that in other embodiments (not shown) the body 26 may have two or more counter-elements 29, and the same number of polarization elements 30 may be provided in the chamber 6. Naturally, the opposite configuration is also possible, i.e. with the chamber 6 including at least one seat or recess and the compensation body 26 having the same number of corresponding reliefs engaging in this recess.

[0062] In the illustrated embodiment, the lateral passage 28 and the polarization counter-element are defined at substantially opposing positions in the cylindrical wall 27 of the body 26. However, even this feature should not be construed in a limiting sense, as in other embodiments (not shown) the passage 28 and the counter-element 29 may be at different angular positions.

[0063] In various preferred embodiments, at least one of the chamber for the passage of fluid and the compensating element comprises engagement means, the engagement means being pre-positioned to maintain the compensating element in a substantially pre-set axial position within the chamber for the passage of fluid.

[0064] In various embodiments, the aforementioned engagement means comprise at least one relief or rib provided on the outer surface of the wall 27 of the body 26. In the illustrated embodiment, the relief or rib is designated by the reference numeral 33 in FIGS. 7-8. The relief or rib extends over at least a part of the circumference of the compensating body 26. The rib 33 may consequently have an annular shape and is configured to elastically couple with the surface 6' of the valve body 2. Additionally or alternatively, the engagement means may be provided on the body 2, for example in the form of one or more reliefs or seats defined on the surface 6', such that the compensating body 26 can elastically interfere with such engagement means, in particular on the outer surface of the wall 27 of the compensating body 26.

[0065] The engagement means may also be interengaging means, i.e. provided for coupling with one another. For example, in the non-limiting case illustrated in the figures, the surface 6' of the chamber 6 may define a seat 34 in which the rib 33 can engage.

[0066] In other embodiments (not shown), the compensating body 26 may have two or more peripheral ribs 33. The chamber 6 may have the same number of corresponding seats 34 as the peripheral ribs 33. Of course, the opposite configuration is also possible, i.e., with the chamber 6 having one or more peripheral ribs and the compensating body 26 may have the same number of corresponding seats 34 extending over at least a portion of the circumference of the compensating body 26.

[0067] In various embodiments, the valve 1 is arranged in a fluid circuit, a fluid system or a fluid device, for example hydraulic or pneumatic. As mentioned above, such a circuit may belong, for example, to an irrigation system, or such a device may be a domestic electrical appliance. Preferably, the valve 1 is applied to a circuit, device or system installed in a vehicle, in particular an automobile. For example, the valve forming the subject of the present invention can be advantageously used in circuits, systems and devices for the control and / or supply of water (or aqueous solutions) in a vehicle, such as a system for washing the windshield or headlights of an automobile, or a system for washing sensors belonging to an autonomous driving system, such as a video camera or a sensor of a LIDAR (Light Detection and Ranging) system, a system for controlling and / or supplying a water-urea solution to an SCR (Selective Catalytic Reduction) system for removing nitrogen oxides from the exhaust gases of an internal combustion engine, or a system for injecting water into an ADI (Anti Detonant Injection) system, etc.

[0068] The use of a preferred embodiment of the valve as shown schematically in Figures 1 to 10 is described in detail below, with the understanding that this description is for the sole purpose of understanding the mechanism of operation and is not intended in any way to limit the scope of protection defined by the appended claims.

[0069] In the illustrated preferred embodiment, when the valve 1 is at rest, i.e., when the actuator assemblies 10-13 are not powered, the opening / closing member 8 carried by the core 9 is in a closed position relative to the valve seat 7, as shown in FIGS. 3 and 5-6. The opening / closing member 8 is biased to this position by a spring 17. In this state, as previously described, no fluid path exists between the inlet 6a and outlet 6b of the chamber 6. When the valve 1 needs to be opened, electricity is supplied to the solenoid 10. This causes the solenoid 10 to generate a magnetic field that exerts an attractive force on the core 9, retracting it relative to the valve seat 7 and thereby compressing the spring 17, as shown in FIG. 4. As previously described, the plate 3, counter-core portion 18, and armature 21 provide a stationary electromagnetic yoke for the actuating coil formed by the winding 11 on the bobbin 12.

[0070] When the aforementioned operating coil is energized, in accordance with techniques known per se, a magnetic attraction force is generated in the yoke, and the counter core part 18 concentrates this force on the core 9, tending to move it back. The displacement of the core 9 correspondingly moves the opening / closing member 8 back relative to the valve seat 7, allowing fluid to circulate freely between the inlet 6a and the outlet 6b of the chamber 6. When the power supply to the solenoid 10 is then interrupted, the magnetic field disappears and the elastic reaction of the spring 17 returns the core 9 to its original position shown in Figure 3, causing the opening / closing member 8 to close the valve seat 7 again.

[0071] When the valve element 8 is in the closed position, residual fluid may remain inside the chamber 6. This risk also arises when the hydraulic system in which the valve is installed undergoes dry operation. During dry operation, only the inlet 6a and the tubular portion 23 are emptied, but some fluid remains in the chamber 6. If this residual fluid freezes, the resulting increase in volume can create a significant thrust that retracts the valve element 8 and the core 9, and thus the counter core portion 18 and the entire actuator assembly 10-13. This thrust can have a force that can compromise the fixation and / or sealing between the valve body 2 and the actuator assembly 10-13. The presence of the compensating body 26 in the chamber 6 limits the amount of residual fluid that can remain in the chamber 6, and the compressible capacity of the body 26 allows the increase in fluid volume to be compensated for.

[0072] FIG. 11 illustrates the case where the hydraulic system with valve 1 is not running dry and there is a freezing fluid F in chamber 6 and upstream and downstream of chamber 6. Comparing FIG. 4 with FIG. 11, it can be seen that the increase in volume of fluid F causes core 9 to retract slightly, to the same extent as under normal operating conditions when solenoid 10 is electrically powered. This phenomenon is made possible by the normal (general) axial compression of body 26, as highlighted in FIG. 11, which allows a significant compensation for the increase in volume of fluid F.

[0073] As mentioned above, Figure 11 relates to the case where there is residual fluid in the hydraulic circuit into which the valve 1 is inserted, i.e. upstream and downstream of the valve 1. In this type of application, the increase in the volume of residual fluid in the tubular portion 23 is substantially compensated by the increase in the volume of residual fluid in the chamber 6 and the outlet 6b, so that no significant deformation of the tubular portion itself occurs.

[0074] However, in other applications, the hydraulic circuit or device into which the valve 1 is inserted may be of the type in which the branches of the circuit upstream and downstream of the valve itself are emptied after use, as described above. It is envisaged that in some hydraulic systems, such as SCR systems for example, an intentional emptying step is provided to ensure that the risks associated with the possibility of freezing are prevented or at least limited. However, this does not exclude the possibility that residues of such liquid may remain inside the chamber 6 in some form.

[0075] In this type of application, therefore, there is no liquid in the tubular portion 23, but instead in the chamber 6. An increase in the volume of residual liquid in the chamber 6 may result in a significant radial compression of the tubular portion 23, which may in turn result in a significant deformation of the annular portion 23, especially considering the small thickness of the portion 23.

[0076] 12 to 14 show this type of situation in the case of a valve without a compensating body 26 in the chamber 6. From these figures it can be seen how an increase in the volume of the fluid F leads to large deformations in the part 23, which in the limit can cause permanent damage or deformations that impair the proper cooperation between the opening / closing member 8 and the valve seat 7.

[0077] 12-14 illustrate that the increase in volume of the frozen fluid causes the tubular portion 23 to deform radially inward, either substantially throughout the entire portion or by stretching only the middle, bottom or top of the portion, and possibly even affecting the valve seat 7. Such deformation may potentially change the cross section of the passage for the fluid, change the sealing area of ​​the valve seat 7, or even cause points of failure in the tubular portion 23.

[0078] This risk can be avoided by providing a compensating body 26 as shown in Figure 15. The body 26, fitted around the tubular part 23, makes it possible to reduce the volume that the residual liquid can occupy. If the residual liquid F freezes, the resulting increase in volume is compensated for by the compression capacity of the body 26, preventing stresses, particularly in the radial direction, of the tubular part 23.

[0079] As is evident from the above description, the valve forming the subject of the present invention achieves several advantages compared to the solutions available in the prior art.

[0080] First, the valve seat 7 is defined by the tubular portion 23, which is made integral with the portion of the valve body 2 made of molded plastic material. This solution eliminates the need for an additional, purposefully dedicated part to perform the function of the valve seat, resulting in a valve with simpler and more precise construction characteristics than solutions known in the art. Furthermore, the small thickness of the tubular portion 23 minimizes the risk that possible shrinkage of the molded plastic material would impair the precision of the valve seat 7 and thus the efficient cooperation between the means for blocking the fluid and the valve seat. Additionally, the compressible or deformable body 26 of the compensating element 25 is advantageously located around the tubular portion 23, within the chamber 6 for the passage of the fluid, eliminating the need for a dedicated housing. This simplifies the valve's construction and improves its compactness. This allows the valve, which forms the subject of the present invention, to be manufactured easily and inexpensively.

[0081] By providing a compensation element 25 surrounding the tubular portion 23, the risk of deformation of the portion 23 and the valve seat 7 is avoided, and as a result the risk of the opening / closing member 8 being closed incorrectly is avoided, as well as the risk of malfunction or narrowing of the cross section of the fluid passage.

[0082] It will be apparent to those skilled in the art that numerous modifications can be made to the valve described by way of example without departing from the scope of the invention as defined in the claims that follow.

[0083] FIG. 16 shows an alternative embodiment in which a pin 9b is centrally mounted within a cavity 9a of the core 9, with a spring 17 positioned around the pin 9b. In addition to guiding the spring 17 during compression, the pin 9b reduces the useful volume of the cavity 9a that can be filled by liquid that may reach the region between the core 9 and the counter-core portion 18. This reduces the volume of this liquid, thereby reducing the negative effects that can result from an increase in the volume of the liquid due to freezing. The pin 9b is preferably made of metal or another rigid material, but can also be advantageously made of an elastic and / or compressible material, such as a material similar to that of the element 25. This allows the pin 9b to deform and / or compress in the event of freezing of the fluid.

Claims

1. 1. A valve for controlling the flow of a fluid, comprising: a valve body having at least one first body portion (2) formed of a polymer or plastic material; a chamber (6) for the passage of a fluid defined within said first body portion (2) and having at least one fluid inlet (6a) and at least one fluid outlet (6b); a valve seat (7) defined within said chamber (6) for the passage of a fluid; a shut-off means (8, 9) for blocking the fluid, displaceable relative to the valve seat (7) to control the flow of the fluid; a compensation element (25) pre-positioned to compensate for a possible increase in the volume and / or pressure of said fluid, the compensating element (25) comprises a compensating body (26) made of an elastically deformable and / or elastically compressible material, the polymer or plastic material of the first body part (2) being harder than the elastically deformable and / or elastically compressible material of the compensating body (26), the compensating body (26) being axially hollow tubular with a peripheral wall (27); The first body portion (2) comprises a generally cylindrical tubular portion (23), the generally cylindrical tubular portion (23) extends into the chamber (6) for the passage of the fluid between the valve seat (7) and one of the fluid inlet (6a) and the fluid outlet (6b); the other of the fluid inlet (6 a) and the fluid outlet (6 b) is disposed transversely to the generally cylindrical tubular portion (23), and the compensating body (26) defines at least one transverse passage (28) between the valve seat (7) and the other of the fluid inlet (6 a) and the fluid outlet (6 b) that allows the passage of the fluid; The compensating body (26) is mounted in the chamber (6) for the passage of the fluid such that the peripheral wall (27) of the compensating body (26) surrounds at least a portion of the generally cylindrical tubular portion (23), and the inner surface of the peripheral wall (27) of the compensating body (26) has a profile that is at least partially complementary to the outer surface of the generally cylindrical tubular portion (23).

2. 2. The valve according to claim 1, wherein the average thickness of the generally cylindrical tubular portion (23) is smaller than the average thickness of a peripheral wall (2b) of the first body portion (2) that defines the periphery of the chamber (6) for the passage of the fluid.

3. 2. A valve according to claim 1, wherein the compensation body (26) has an axially hollow cylindrical shape.

4. 2. The valve according to claim 1, wherein the compensating body (26) is arranged in the chamber (6) for the passage of the fluid such that a first longitudinal end (31) of the circumferential wall (27) of the compensating body (26) is located above the valve seat (7) and a second longitudinal end (32) of the circumferential wall (27) of the compensating body (26) is located below the other of the fluid inlet (6a) and the fluid outlet (6b).

5. 2. A valve according to claim 1, wherein the outer surface of the peripheral wall (27) of the compensating body (26) has a profile that is at least partially complementary to an inner surface (6') of at least one of the first body parts (2) that defines from the surroundings the chamber (6) for the passage of the fluid.

6. one of a polarization element (30) and a polarization counter-element (29) is defined within the chamber (6) for the passage of the fluid; the compensation body (26) has the other of the polarization element (30) and the polarization counter element (29); 2. The valve of claim 1, wherein the polarization element (30) and the polarization counter element (29) are pre-positioned to keep the compensation body (26) in a predetermined angular position within the chamber (6) for the passage of the fluid.

7. A polarization element (30) is defined within the chamber (6) for the passage of the fluid; The compensation body (26) has a polarization counter element (29), the polarization element (30) and the polarization counter-element (29) are pre-positioned to keep the compensation body (26) in a predetermined angular position within the chamber (6) for the passage of the fluid; 2. The valve according to claim 1, wherein the at least one transverse passage (28) and the at least one polarization counter element (29) are defined at opposite positions in a generally cylindrical peripheral wall (27) of the compensation body (26).

8. 8. A valve according to claim 7, wherein the at least one transverse passage (28) is constituted by a recess extending from a first longitudinal end (31) of a generally cylindrical peripheral wall (27) of the compensation body (26) towards a second longitudinal end (32) opposite the first longitudinal end (31), and the at least one polarization counter-element (29) is constituted by a recess extending from the second longitudinal end (32) of the generally cylindrical peripheral wall (27) towards the first longitudinal end (31).

9. 2. A valve according to claim 1, wherein at least one of the chamber (6) for the passage of the fluid and the compensating element (25) has pre-arranged engagement means (33, 34) for maintaining the compensating body (26) in a predetermined axial position within the chamber (6) for the passage of the fluid.

10. 10. A valve according to claim 9, wherein the engagement means comprise at least one rib or relief (33) extending over at least a portion of the periphery of the compensation body (26), possibly in combination with a corresponding seat or recess (34) defined in a surface that delimits the periphery of the chamber (6) for the passage of the fluid, or vice versa.

11. A fluidic device comprising a valve according to any one of claims 1 to 10.

12. A compensating element (25) for a valve (1), comprising: The valve (1) comprises at least one first body portion (2) defining a fluid passage chamber (6), at least one inlet (6a) and one outlet (6b) for fluid fluidly connected with the fluid passage chamber (6), and a valve seat (7) within the fluid passage chamber (6); the at least one first body portion (2) further defines a generally cylindrical tubular portion (23) extending between the valve seat (7) and one of the at least one inlet (6a) and one outlet (6b); the fluid passage chamber (6) is defined laterally between an inner surface (6') of the at least one first body portion (2) and the generally cylindrical tubular portion (23); said compensation element (25) being pre-positioned to compensate for a possible increase in volume and / or pressure of said fluid; The compensating element (25) comprises an axially hollow compensating body (26) made of an elastically deformable and / or compressible material, The compensation body (26) a tubular peripheral wall (27) pre-arranged within the fluid passage chamber (6) to surround the valve seat (7), the outer surface of the tubular peripheral wall (27) being configured to directly face the inner surface of the first body portion (2) and the inner surface of the tubular peripheral wall (27) being configured to directly face the outer surface of the generally cylindrical tubular portion (23); a transverse passage (28) provided in the tubular peripheral wall (27) and configured to allow passage of the fluid between the at least one inlet (6 a) and the one outlet (6 b), the transverse passage (28) having a recess extending in the axial direction of the tubular peripheral wall (27) of the compensating body (26) from a first longitudinal end (31) of the tubular peripheral wall (27) towards a second longitudinal end (32) of the tubular peripheral wall (27); an engagement element (33) pre-positioned to maintain the compensation body (26) in a predetermined position within the fluid passage chamber (6) and / or a polarization element (29) pre-positioned to maintain the compensation body (26) in a predetermined angular position within the fluid passage chamber (6); A compensation element comprising:

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