Mechanical reset device for safety valves

Abstract

A reset device (50) for a safety valve has a device body (51) with an inlet (52) and an outlet (53) between which a duct (C) extends in an axial direction, the inlet (52) and the outlet (53) having an inlet fitting (52a) and an outlet fitting (53a) configured for coupling with an outlet of the safety valve (1) and a generic pipe, respectively, wherein on the device body (51) a reset mechanism (76-78) is mounted, which comprises: - a reset member (76) inside the duct (C), mounted slidably in the axial direction between an inoperative position and an operative position, - an actuating member (77, 78), operable to cause the displacement of the reset member (76) between the inoperative position and the operative position, wherein the actuating member (77, 78) includes: - a shaft (77a) extending inside the duct (C) transversely to the axial direction, the shaft (77a) being angularly rotatable below the reset member (76) in a respective seat (79, 82, 83) defined by the device body (51), - a cam (78) fixed in rotation on the shaft (77a), having a surface (78d') susceptible of interacting with a surface of the reset member (76) during a rotation of the shaft (77a), to move the reset member (76) at least from the inoperative position to the operative position.

Description

[0001] Mechanical reset device for safety valves

[0002] DESCRIPTION

[0003] Field of the invention

[0004] The present invention relates generally to safety valves intended for connection between a liquid supply source and an apparatus or system using said liquid, configured to measure the volume of liquid passing through the valve itself and to interrupt the flow when the measured volume reaches or exceeds a preset volume.

[0005] State of the art

[0006] Safety valves of the indicated type are known, for example from document GB2055454 A.

[0007] Referring, for example, to the field of domestic water-conducting appliances, a safety valve of the indicated type is typically applied between a water draw-off point from a water network and the appliance at issue, particularly upstream of its supply pipe. The valve is configured to measure the flow rate of water continuously flowing from the water network to the appliance, and to interrupt the flow in case the quantity of water supplied is equal to or greater than a certain safety limit, which can be predefined during production or set by the user.

[0008] Referring to this example, the known safety valve typically comprises a mechanical flow metering arrangement, a mechanical valve arrangement and, often, a mechanical adjustment arrangement intended to allow setting of said safety limit. In this way, if the safety limit predefined or set for the valve is 50 liters, upon detection of a corresponding volume of water, detected via the flow metering arrangement, the safety valve proceeds to interrupt the flow, via its internal valve arrangement. The valve is generally designed to detect said quantity of water corresponding to the safety limit in the presence of a continuous flow, i.e., in the absence of interruptions of the flow itself, as this circumstance is indicative of the fact that the served appliance has not functioned correctly. Conversely, when the appliance functions correctly, the supply of water occurs at successive intervals, each time reaching individual quantities of supplied water that are lower than the safety limit: for this purpose, consider a washing machine, whose operatingcycle typically involves a succession of individual treatment steps, each of which presupposes loading a given quantity of water into the machine that is lower than the safety limit. Obviously, the sum of the individual quantities of water necessary for performing the various steps may exceed the safety limit but, as said, these quantities are loaded in a non-continuous manner (and each step of the operating cycle usually ends with a discharge of water from the appliance).

[0009] To give an even more specific example, suppose that the cycle being executed on the appliance requires, for performing one of its treatment steps, a loading of 30 liters of water: this quantity is therefore drawn continuously from the water network, and once this quantity is reached (measured internally to the appliance, for example via its pressure switch) the appliance interrupts the water supply, for example by causing the closure of its own loading valve. In this circumstance, the safety valve does not cause the closure of its internal valve arrangement, given that its related safety limit is set to 50 liters. The valve is, however, able to detect, via its internal flow meter, the stop of the flow at the end of the supply of the 30 liters, and consequently reset the count performed by said flow meter up to that moment. Therefore, even if a second water loading is subsequently performed (for example again 30 liters, for performing a subsequent step of the treatment cycle), the flow meter will start a new count of liters, starting from zero, and the safety valve will not perform any flow stop via its valve arrangement (unless, of course, said second water loading continues beyond 50 liters, which is a condition indicative of a malfunction of the appliance).

[0010] Completely mechanical safety valves are often used as an alternative to similar electrical safety valves, as they have more contained dimensions in the axial and radial directions, which facilitates their placement even in tight spaces (electrical safety valves must, for example, be equipped with a backup battery). Such mechanical valves also do not presuppose connection to an electrical network, with the added advantage of operating correctly even in the absence of mains voltage (black-out), i.e., without the need for a backup battery.

[0011] Following the intervention of a mechanical-type safety valve, the shutter of its valve arrangement moves stably into a closed position of a corresponding valve seat. In order to restore the operability of the safety valve, the shutter must be returned to its respective stable open position, and this operation must be performed manually, forexample by imparting an axial or upward push to the shutter itself or to another part associated therewith, typically acting through the outlet opening of the valve itself, and for this purpose the pipe connected to the user apparatus must be disconnected. The reset operation is typically performed using a generic rod-like device, such as a screwdriver, and is relatively delicate, given that the internal components of the safety valve, such as its valve arrangement and the associated flow metering arrangement, are made of plastic material: an error in performing the operation can therefore also cause irreversible damage to the safety valve, and for this reason it is advisable that the reset be performed by a specialized technician, in any case with particular care.

[0012] Object and summary of the invention.

[0013] In its general terms, the present invention aims to indicate a specific device for performing the reset of a safety valve of the indicated type, which is simple, convenient and safe to use in view of the need to restore the operability of the valve itself.

[0014] This aim is achieved according to the present invention by a reset device or tool having the characteristics indicated in the attached claims. The claims constitute an integral part of the technical teaching provided here in relation to the invention.

[0015] Brief description of the drawings

[0016] Further objects, characteristics and advantages of the invention will become apparent from the detailed description that follows, made with reference to the accompanying drawings, provided purely by way of explanatory and non-limiting example, in which:

[0017] - figures 1 and 2 are schematic perspective views of a reset device according to possible embodiments of the invention, shown in a decoupled and coupled condition, respectively, with a generic safety valve;

[0018] - figure 3 is a schematic exploded perspective view of a reset device according to possible embodiments of the invention;

[0019] - figure 4 is a schematic section of a reset device according to possible embodiments of the invention:

[0020] - figures 5 and 6 are, respectively, an exploded perspective view of two components of the reset device of figures 3-4, and a corresponding detail on a larger scale;

[0021] - figures 7 and 8 are schematic and sectioned perspective views, from differentangles, of a generic safety valve, in an open condition;

[0022] - figure 9 is a schematic section of the safety valve of figures 7-8;

[0023] - figure 10 is a schematic and sectioned perspective view of the safety valve of figures 7-9, in a closed condition;

[0024] - figure 11 is a schematic section of the safety valve of figure 10;

[0025] - figure 12 is a schematic and sectioned perspective view of the safety valve of figures 7-9, coupled to which is a reset device according to possible embodiments in a first condition;

[0026] - figures 13 and 14 are schematic sections, orthogonal to each other, of the safety valve and the reset device of figure 12;

[0027] - figures 15 and 16 are a schematic and sectioned perspective view and a schematic section, respectively, of the safety valve and the reset device of figures 12-14, in a second condition;

[0028] - figures 17 and 18 are a schematic and sectioned perspective view and a schematic section, respectively, of the safety valve and the reset device of figures 12-14, in a third condition;

[0029] - figures 19 and 20 are respectively a schematic perspective view and an exploded view of a mechanical reset device according to an alternative version which is not an object of the invention; and

[0030] - figure 21 is a schematic section of a safety valve of the type shown in figures 7-9, with a reset device according to figures 19-20 coupled therewith.

[0031] Detailed description of preferred embodiments of the invention

[0032] The reference to "an embodiment" . to "various embodiments" and the like, within this description is intended to indicate that at least one particular configuration, structure, or feature described in relation to an embodiment is included in at least one embodiment. Therefore, phrases such as "in one embodiment" . "in an embodiment" . "in various embodiments" and the like, possibly present in different places of this description, are not necessarily referring to the same embodiment, but may instead refer to different embodiments. Furthermore, particular conformations, structures or features defined within this description may be combined in any suitable manner in one or more embodiments, even different from those depicted. The numerical and spatial references(such as "upper", "lower", "high", "low", "front", "rear", "vertical", etc.) used here, particularly in reference to the examples in the figures, are for convenience only and therefore do not define the scope of protection or the extent of the embodiments. In the present description and in the attached claims, the generic term "liquid" shall be understood to include water or other liquids, including mixtures and solutions containing water and / or other liquids. Similarly, the generic definition "liquid-conducting appliances and systems" shall be understood to include all those devices, appliances, plants and systems that are supplied or that, more generally, use at least one liquid (such as, for example, domestic appliances or systems, sanitary heating systems, heating or air conditioning systems, irrigation systems, etc.). In the figures, the same reference numbers are used to indicate analogous or technically equivalent elements.

[0033] Referring to figures 1-2, reference 1 indicates as a whole a generic safety valve, for example of a completely mechanical type, a possible construction of which will be described later. The valve 1 has a body 2 preferably formed in at least two parts 2a, 2b coupled together in a sealed manner, said parts 2a and 2b possibly being formed of molded plastic material. The body 2 is axially hollow and defines internally a duct for the passage of a liquid flow, within which a flow metering arrangement and a valve arrangement are housed. In the upper part 2a of the body 2, an inlet 3 of the aforesaid duct is defined, at a corresponding fitting, which can be a threaded fitting, or comprising a female thread. In the lower part 2b of the body 2, an outlet 4 of the aforesaid duct is instead defined, at a corresponding fitting, which can be a threaded fitting, or comprising an external thread. The aforesaid fittings can be of a complementary type to each other.

[0034] Reference 50 indicates as a whole a mechanical reset device according to possible embodiments, which is susceptible to being occasionally coupled to a safety valve of the type previously indicated, to be used as a tool for the purpose of restoring the operability of the valve itself, or to be coupled stably to the valve, in case of particular uses.

[0035] The device 50 has a respective device body 51, configured for separable coupling to the outlet of a safety valve, such as the outlet 4 of valve 1. For this purpose, also referring to figures 3-4, the device body 51 has an inlet 52 and an outlet 53, between which a duct C extends in the axial direction (figure 4). The inlet 52 and the outlet 53 are preferably defined at an inlet fitting 52a and an outlet fitting 53a, respectively. The fittings 52a and 53a are preferably configured as threaded fittings: in the example, the fittings 52aand 53a comprise a female thread and a male thread, respectively. It is possible to provide fittings of another type, depending on the type of fittings of the inlet and / or outlet of valve 1. As can be seen, the reset device 50 constitutes an autonomous component structurally distinct from the safety valve 1, although configured to cooperate therewith for the purpose of restoring its operability.

[0036] In various embodiments, the inlet fitting 52a and the outlet fitting 53a of the device 50 are complementary to each other. Preferably, the fitting 52a of the device 50 is configured for coupling with the outlet fitting 4 of valve 1, and can therefore be complementary thereto, while the fitting 53a of the device 50 is of a type analogous to the outlet fitting 4 of valve 1, for example in terms of diameter and thread pitch: in this way, in the use of device 50, a pipe originally connected to the fitting 4 of the valve 1 can be separably connected to the fitting 53a of the device 50. As can be seen, the device 50 is configured to be coupled to valve 1 in a separable manner for occasional use, or it can be left associated with valve 1 in a more stable manner depending on the application.

[0037] In various advantageous embodiments, the inlet 52 and the outlet 53 of the device 50, or the respective fittings 52a and 53a, are substantially coaxial with each other and with respect to an axis X of the duct.

[0038] In preferred embodiments, the device body 51 comprises at least a first body part 60 and a second body part 70, which have a generally tubular shape. The two body parts 60 and 70 are coupled axially to each other, particularly in accordance with said axis X. The body part 70 defines at least a portion of the duct C, to which the threaded through cavity of the body part 60 is coaxial.

[0039] The first body part 60, hereinafter also referred to for simplicity as the upper part, includes the inlet fitting 52a, while the second body part 70, hereinafter also referred to for simplicity as the lower part, includes the outlet fitting 53a, and has a reset mechanism mounted thereon, described later.

[0040] In preferred embodiments, the two body parts 60 and 70 are both formed of molded plastic material, for example a thermoplastic material, although a construction of the part 60 in metal material is not excluded.

[0041] In preferred embodiments, the upper part 60 is snap-coupled onto the lower part 70, and is susceptible to rotating relative thereto, particularly around the axis X of the duct C. The upper part 60 could however be structured and coupled differently to thelower part 70, for example via a quick-coupling fitting.

[0042] In various particularly advantageous embodiments, the upper part 60 is configured as a rotatable ring nut, integrating the inlet fitting 52a, i.e., the previously mentioned female thread.

[0043] Referring in particular to figures 3 and 4, in various embodiments, the upper part 60 is obtained in a single piece by molding plastic material and presents a peripheral wall 61 generally cylindrical, provided with a plurality of radial apertures or windows 62, preferably equidistant along the circumference of the same wall 61. At each window 62, at least one elastically flexible engagement element 63 is defined, particularly in the form of a tooth or tab. Preferably, at each window 62, at least two engagement elements 63 are provided. The engagement elements 63 rise from a base portion 61a of the peripheral wall 61, and are generally inclined, so as to converge towards the center of the upper part 60 or towards the axis X. A head portion 61b of the peripheral wall 61 is preferably provided peripherally with gripping elements 64, for example a series of axial reliefs or ribs, to facilitate rotation of the upper part 60, also manually.

[0044] In various embodiments, the lower part 70 is obtained in a single piece by molding plastic material, and presents a peripheral wall generally cylindrical 71, whose lower portion integrally defines the outlet fitting 53a, i.e., the previously mentioned male thread.

[0045] In various embodiments, the upper portion of part 70, i.e., of its wall 71, is shaped so as to define an annular seat, indicated with 72 only in figures 3 and 5, for a sealing ring 73.

[0046] In embodiments where the upper part 60 of the device body 51 is rotatable, the upper portion of part 70, i.e., of its wall 71, presents an annular protrusion 74, particularly for the snap engagement of the upper part 60. More generally, the body parts 60 and 70 are provided with mutual coupling means, such as those indicated with 63 and 74, preferably capable of allowing a relative angular movement.

[0047] Referring to the preferential case illustrated, the annular protrusion 74 has an outer circumference that is smaller than the inner circumference of the peripheral wall 61 of the upper part 60, and preferably also larger than the circumference identified by the tips of the engagement elements 63 of the same upper part 60, this latter circumference being preferably (but not necessarily) at least slightly larger than the circumference of the cylindrical wall 71. In this way, the upper part 60 can be fitted from above onto the lowerpart 70, and pushed downward so that the engagement elements 63 flex elastically outward as a result of interference with the annular lug 74. When, during the downward movement of part 60, the tip of the engagement elements 63 passes beyond the annular protrusion 74, the same elements 63 can return elastically to the original condition, determining the snap engagement between parts 60 and 70, with the tips of elements 63 now below the protrusion 74, and the possibility of freely rotating the upper part 60 relative to the lower part 70.

[0048] Preferably, the peripheral wall 71 of the lower part 70 defines a further annular centering protrusion 75, arranged below the protrusion 74 and having a maximum circumference equal to or slightly smaller than the inner circumference of the wall 61 of the upper part 60. The lug 75, preferably having a radiused surface, is positioned so as to be in contact or facing with minimal clearance to the inner surface of the aforesaid wall 61, at its lower portion 61a, in order to guarantee a substantially coaxial arrangement between the body parts 60 and 70.

[0049] As previously indicated, on the device body 51, and specifically on its lower part 70, a reset mechanism is mounted. Said reset mechanism comprises a reset member, indicated as a whole with 76 in figures 3 and 4, which is arranged inside the portion of the duct C defined in the lower part 70, and is mounted slidably in the axial direction between a lowered inoperative position and a raised operative position. As can be seen, the reset member 76 is a component proper to the reset device 50, i.e., it structurally belongs to it, being mounted on the device body 51 and guided by the same body inside the respective duct C in the displacement between the inoperative and operative positions.

[0050] As clarified later, the reset member 76 is intended to interact with a valve arrangement internal to the safety valve 1 and for this purpose, in various embodiments, the reset member 76 has a central reset pin 76a, which extends substantially along the axis X of the duct C. Preferably, the reset member 76 and / or the reset pin 76a are aligned or centered relative to the body part 60 and / or to the fitting 52a, and aligned or centered with the inlet 52 and with the outlet 53, as well as with the fitting 53a of the body part 70. As will be seen, in the coupled condition of the device 50 to the valve 1, the displacement of the reset member 76 is configured to move an element of the internal valve arrangement of the associated valve, in particular of a shutter body thereof or of a protruding movable portion thereof.In various embodiments, the reset member 76 is provided with guiding and / or centering means relative to the duct C, in order to guarantee precise sliding in the axial direction. In the preferential example illustrated, the member 76 comprises a peripheral portion 76b, which is connected coaxially to the central pin 76a, particularly via a plurality of radial elements 76c; in an alternative version, the peripheral portion could be absent, and only the plurality of radial elements 76c could be provided.

[0051] The height of the peripheral portion 76b, when present, is preferably equal to a fraction of the height of the central pin 76a.

[0052] In the example, the peripheral portion 76b is annular, or has a circular-ring shape, and is connected to the pin 76 via a plurality of radial elements in the form of fins 76c, preferably equidistant from each other, which extend radially from the pin 76a. The fins 76c preferably have a height that is greater than the height of the annular portion 76b, or the height of the annular portion 76b is equal to a fraction of the height of the fins 76c.

[0053] The height of the fins 76c is preferably less than the height of the pin 76a, so that at least a portion of the latter protrudes in height beyond the upper edge of the same fins; indicatively, the height of the fins 76c can be between half and four -fifths of the height of the pin 76b. Preferably, at least a portion of the central pin 76a protrudes downward beyond the lower edge of the fins 76c, in order to better interact with a cam described later.

[0054] The annular portion 76b is preferably located at an intermediate lateral zone of the fins 76c, for example at a generally lower region of the reset member 76 (indicatively in the lower half of the fins, with reference to their height).

[0055] Preferably, the fins 76c are connected to the annular portion 76b only at their outer edge, so that, in any case, between the same fins 76c and the peripheral portion 76b, axial passages are defined (not visible in the figures), of approximately triangular or trapezoidal profile with curved bases, such as to allow the transit of liquid.

[0056] In various preferential embodiments, the peripheral portion 76b has an outer surface, therefore a circumferential surface, which is slidably engaged with the inner circumferential surface of the duct C. Preferably, the outer surface of the annular portion 76b has a height equal to a fraction of the height of the central pin 76a. Indicatively, the height of the outer surface of the annular portion 76b can be less than half or three-quarters of the height of the central pin 76b. In the case where the peripheral portion 76b is absent,each fin 76c has an outer edge or surface, preferably arcuate, which is slidably engaged with the inner circumferential surface of the duct C.

[0057] Preferably, the outer surface of the annular portion 76b, if provided, has a height equal to a fraction of the height of the central pin 76a. Indicatively, the height of the external surface of the annular portion 76b can be less than half or three-quarters of the height of the central pin 76b.

[0058] Preferably, the central pin 76a, the annular peripheral portion 76b (when provided) and the radial elements represented by the fins 76c are formed in a single piece, particularly of molded plastic material.

[0059] In various embodiments, the device body 51 comprises at least one stop element, or similar constraint or positioning element for the reset member 76, in particular configured to prevent complete slipping out of the same reset member 76 through the inlet 52 of the device body 51. In the non-limiting example shown, at the inner surface of the duct C, particularly in its portion defined by the lower part 70, there is at least one stop protrusion, partially visible only in figures 12, 14 and 16, where it is indicated with Ci, configured to prevent slipping of the reset member 76 out of from the duct C. In preferential embodiments, the at least one stop element Ci is substantially tooth- or protrusion-shaped, preferably defining an inclined ramp descending towards the inlet fitting 52. The reset member 76 can be inserted from above into the duct portion defined by the lower body part 70 and pushed downward, so that a section of the peripheral portion 76b of the same member 76 flexes elastically inward as a result of interference with the aforesaid protrusion, preferably facilitated by aforesaid ramp.

[0060] When, during the downward movement of the member 76, the annular peripheral portion 76b passes beyond the ramp, the aforesaid section of the annular peripheral portion 76b can return elastically to the original condition, so that extraction of the member 76 upward cannot occur. In this preferential configuration, the peripheral portion 76b therefore obtains an engagement and / or positioning element for the reset member 76, preferably of an annular shape to allow easy assembly without having to worry about the relative angular position within the duct C, i.e., to allow coupling with the protrusion Ci substantially in any angular position. According to possible variants, different engagement and / or positioning means for the member 76 could be adopted, for example also providing only a single portion of peripheral element 76b, and providing between themember 76 and the duct portion defined by the body part 70 suitable polarization means, or means intended to allow insertion of member 76 into the portion of the duct C in a unique angular position, in which subsequent coupling between the aforesaid engagement and / or positioning means is guaranteed.

[0061] The extraction of member 76 downward is, on the other hand, prevented by the presence of an underlying actuation member, described below.

[0062] The reset mechanism that equips the device 50 further comprises an actuating member, which is operable to cause the displacement of the reset member 76 between the inoperative and operative positions. As explained below, said actuating member includes a shaft, which extends inside the duct C transversely to the axis X thereof, and which is angularly rotatable around a respective axis below the reset member 76, in a respective seat defined by the device body 51, particularly of its lower part 70. The presence of this transverse shaft prevents the slipping out of the reset member 76 downward, i.e., through the outlet 53. The reset mechanism further comprises a cam on the aforesaid shaft, which has a cam surface designed to interact with a surface of the reset member 76 during a rotation of the shaft itself, to move the reset member 76 at least from the inoperative position to the operative position. As can be seen, therefore, the reset mechanism of the device 50 is configured to obtain a motion transformation whereby a rotation manually imparted to the actuation member is converted into an axial displacement of the reset member 76.

[0063] Referring in particular to figures 3 and 4, in the example shown the actuating member comprises an element, indicated as a whole with 77, which is rotatable around a respective axis Y (figure 4) transverse to the duct C, particularly substantially perpendicular to axis X. The rotatable element 77 comprises the aforementioned transversely disposed shaft, indicated with 77a. The rotatable element 77 has an end portion accessible outside the duct C, which is configured to be operable by a user. Preferably, this end portion is shaped to be directly manually graspable by the user, in order to impart the necessary rotation to the shaft 77a. Preferably, the operable end portion is formed in a single piece with the shaft 77a, particularly of molded plastic material. The end portion comprises a graspable knob, which in the non-limiting example shown comprises a flange formation 77b of the shaft 77a, provided frontally with a projecting wall 77c.The actuating member further comprises a cam 78 on the shaft 77a, having a cam surface which is configured to interact with a surface of the reset member 76 during a rotation of the shaft 77a, to displace the reset member 76 at least from the inoperative position to the operative position. As can be seen, the cam 78 is configured to cause a controlled advancement of the reset member 76 along the duct C of the device 50, so as to develop in the device itself an axial thrust destined to be transferred to the associated valve.

[0064] As visible particularly in figure 3, in various embodiments, the cam 78 has a body, preferably formed of molded plastic material, having a central part 78a provided with an axial passage 78b, configured to be coupled to the shaft 77a without possibility of rotation. In the example, the passage 78b is provided with at least one axial groove 78C, in which at least one corresponding axial protrusion 77a' defined in an intermediate zone of the shaft 77a is adapted to engage. From the central part 78a of the cam body 78, a portion 78d protrudes radially, which extends eccentrically relative to the passage 78b, and which performs the functions of a cam in the strict sense. In the non-limiting example, two axial protrusions 77a' are provided in diametrically opposite positions on the shaft 77a.

[0065] The portion 78d has a peripheral surface, indicated with 78d' in figures 14-18, which obtains a cam surface, susceptible to interacting with the reset member 76, particularly with the lower end of its central pin 76a.

[0066] The device body 51 has a lateral passage, particularly in the lower body part 70, through which at least the shaft 77a can be inserted. In the example, said opening is shaped to define, towards the outside of the lower part 70, a cylindrical seat or housing 79 susceptible to receiving internally at least one sealing element 80, for example one or two o-ring type seals, susceptible to cooperating in sealing with a corresponding portion of the shaft 77a in order to avoid leakage of liquid to the outside of the device body 51. The sealing element or elements 80 can be maintained in position within the housing 79 via the flange formation 77b of the rotatable element 77.

[0067] In various embodiments, the reset mechanism of the device 50 includes at least one elastic element, configured to urge the actuation member, i.e., its shaft 77a, into a respective rest position, to which the inoperative position corresponds, in which the reset member 76 is in its respective lowered inoperative position. In preferred embodiments,the cylindrical housing 79 (particularly its outer surface) conveniently also serves as an element for the positioning of a torsion spring 81, interacting between the rotatable element 77 and the lower body part 70.

[0068] For this purpose, and as shown in figures 3, the device body 51, or its lower part 70, can present in a peripheral position relative to the housing 79 an abutment formation 70a for one end of the spring 81, the other end of the spring instead finding an abutment with a rear projection 77b' of the rotatable element 77. The device body 51, or its lower part 70, further has a stop formation 70b, also in a peripheral position relative to the housing 76, against which the aforesaid rear projection 77b' is maintained in abutment by the spring 81 in the aforesaid rest position of the rotatable element 77 (in the example, the spring 81 urges the rotatable element 77 counterclockwise).

[0069] In various embodiments, the device body 51 defines, inside the duct C, positioning elements configured to maintain the cam 78 in a substantially predefined position along the shaft 77a.

[0070] Referring in particular to figure 4, in the exemplary case, the lower body part 70 defines, in a position axially aligned with the housing 79, a through tubular seat 82 of circular cross-section, protruding towards the inside of the duct C in the radial direction, within which a corresponding intermediate portion of the shaft 77a is received; in a diametrically opposite position of the duct C a similar tubular seat 83 is provided, having a closed bottom defined by the peripheral wall of the lower body 70, where this seat 83 protrudes radially towards the inside of the duct C and within it a corresponding end portion of the shaft 77a is received.

[0071] Preferably, the length of the two tubular seats 82 and 83, i.e., the distance between their facing ends, is substantially coincident or slightly greater than the length of the central part 78a of the cam body 78, as clearly noted in figure 4. In this way, the correct axial positioning of the cam 78 along the shaft 77a is guaranteed, without the need for specific means for mutual fixing. The tubular seats 82 and 83 are also configured to maintain the rotatable element 77 in the correct operative position, obtaining at least part of the rotation seat thereof.

[0072] In various embodiments, the rotatable element 77 and the device body 51 are configured to prevent unintentional slipping of the first out of the second, with the shaft 77a of the rotatable element 77 being for this purpose provided with at least oneprotrusion, suitable to stop any axial extraction of the shaft itself from its respective rotation seat 82-83: for this purpose, the upstream part 82 of said seat 82-83 is provided with a groove aimed at allowing the passage of the aforesaid protrusion, but without subsequently, in the normal and correct use of the reset device 50, said protrusion and groove being able to become axially aligned with each other again.

[0073] Referring in particular to figures 5-6, in a preferred embodiment, said at least one stop protrusion corresponds to the at least one protrusion 77a' used to constrain the cam 78 to the shaft 70a. On the other side, the upstream part of the rotation seat of the shaft 70a, here represented by the tubular seat 82, is provided with at least one respective axial groove, configured to allow the insertion of the at least one protrusion 77a'. In the nonlimiting example, since two opposite protrusions 77a’ are provided on the shaft 77a, the tubular seat 82 is also provided with two diametrically opposite axial grooves, indicated with 82a in figures 5-6.

[0074] The angular position of the at least one axial groove 82a is such that, in a condition of correct operability of the reset device 50, the at least one protrusion 77a' is never axially aligned with said groove. In other words, referring to the example shown, during the assembly of the device 50, the shaft 70a of the rotatable element 77 can be inserted through the seats 79, 82 and 83, taking care that each protrusion 77a' is axially aligned with the corresponding groove 82a (in this phase, the cam 78 will be correspondingly positioned inside the duct C, so that its axial grooves 78c of figure 3 are also aligned with the grooves 82a). In the condition of complete insertion, the protrusions 77a', with the cam 78 on them, will therefore be located in the space between the facing ends of the seats 82 and 83. The action of the torsion spring 81 then has the effect of urging the rotatable element 77 counterclockwise, in order to keep the rear projection 77b' of the flange formation 77b of the same rotatable element 77 abutting against the stop formation 70b of the lower body part 51 (see figures 3-4).

[0075] After assembly, for the correct use of the reset device 50, as described later, the rotatable member 77 can be rotated by 90° (clockwise) only within an angular field that does not include a position such that the protrusions 77a' become again axially aligned with the grooves 82a of the seat 82: in this way, given that the diameter identified by the axial protrusions 77a' is greater than the internal diameter of the tubular seat 82, the head ends of the axial protrusions 77a' can only rest on the end of the tubular seat 82 internalto the duct C, without the rotatable element 77, i.e., its shaft 77a, being able to be extracted from its respective rotation seat 82-83.

[0076] The reset device 50 is intended to be used to restore the operability of the safety valve 1 after an intervention by the latter, as explained in the introductory part.

[0077] For purely exemplary purposes, for a better understanding of the invention, figures 7-11 show a possible construction of a safety valve 1, which is preferably a mechanicaltype safety valve. In various embodiments, the general structure of the valve 1 is of a type similar to that described in GB2055454 A.

[0078] As already indicated, the valve 1 has a housing body 2 including a respective upper part 2a and a respective lower part 2b, preferably coupled by means of a threaded coupling, not indicated but clearly visible, for example, in figures 7-11 (although a different type of coupling is not excluded, for example bayonet, snap-fit, with welding or gluing).

[0079] On one of the two parts, preferably the upper part 2a, an externally defined polygonal faceted portion can be provided, to facilitate the installation of the valve using a suitable tightening device, particularly downstream of a water network tap, or similar hydraulic connection. For this purpose, the valve 1 presents an inlet fitting and an outlet fitting, which integrate the previously mentioned inlet 3 and outlet 4, here of the threaded type, female and male respectively. At the inlet 3, an annular gasket with an associated filter, indicated with 8 in figures 7-11, can be mounted.

[0080] The valve 1 comprises a first shutter 10, or upstream shutter, associated with the upper end of an axial shaft 11 mounted idly inside the housing body 2. The lower end of the shaft 11 is engaged - via a corresponding axial hollow part 23b of a pinion 23 described later (see for example figures 9 and 11) - with a contrast helical spring 12 (figures 9 and 11), housed inside a second shutter (or downstream shutter, hereinafter indicated with 21). The axial shaft 11, in addition to rotating, can translate axially due to the pressure of the liquid entering the valve 1.

[0081] The first shutter 10 is provided superiorly with a flow deflector element 10a, for example constituted by a series of blades arranged radially. In the rest condition of the valve (shown in figures 7-9), the deflector 10a is at a level higher than a first valve seat 13, against which a sealing ring 10b of the first shutter 10 is intended to abut. In operation, in the presence of a liquid flow entering the valve 1, the first shutter 10 lowers, alsolowering the shaft 11, in contrast to the action of the spring 12, so as to allow the passage of liquid through the valve seat 13.

[0082] Below the first shutter 10, and in a coaxial position relative to the shaft 11, there is a diffuser 14, provided with helical or inclined ribs or blades 14a, intended to direct the flow against the blades 15a of an underlying impeller 15, mounted idly on the axial shaft 11. The blades 14a of the diffuser 14 are preferably inclined in the opposite direction to the blades 15a of the impeller 15.

[0083] A worm screw 16 is keyed inferiorly to the impeller 15, which is coupled to a reduction mechanism, here comprising respective pairs of gears 17a-17b and 18b-18d, for example with skew axes, constituted by corresponding teeth and worm gears formed at the ends of rotating bushings 17 and 18, supported in a rotatable manner on an internal diaphragm 19 which transversely subdivides the interior of the valve body.

[0084] Regardless of the specific configuration of the reduction mechanism 17-18, said diaphragm 19 presents a plurality of apertures 19a for the passage of liquid, as well as supports (not indicated) for the gears 17, 18 of the reduction mechanism, so that said gears are mutually engaged (worm gear 17a engaged with the worm gear 16, worm gear 17b engaged with the teeth 18a and worm gear 18b engaged with the pinion indicated with 23). The incoming liquid passing through the apertures 19a of the diaphragm 19 collects towards the bottom of the lower body part 2b, which for this purpose preferably has a flared shape, suitable for constituting a lead-in for the liquid towards an outlet valve, disposed at the outlet 4, or at its threaded fitting.

[0085] Said outlet valve comprises a shutter body 21 and a valve body 22. The shutter body 21 is fixed in rotation with the lower end of the axial shaft 11, via the aforementioned axial hollow part 23b of the pinion indicated with 23. The shutter body 21 is generally hollow, and has a lower head 21a shaped as a stem, which is guided axially inside the valve body 22. Within the shutter body 21 is the aforementioned contrast spring 12, operative to push on the lower end of the shaft 11, or to bring the first shutter 10 into its respective closed position of the first valve seat 13. A control mechanism of the shutter body 21 is also mounted on the shaft 11, which comprises the aforementioned pinion 23, provided with a frontal toothing 23a (figures 10-11). In the lowered condition of the axial shaft 11, i.e., when a liquid flows from above and pushes the first shutter 10 downward, the frontal gear 23a of the pinion 23 is engaged with a lamellar spring 24 (figures 10-11),housed inside the upper part of the shutter body 21, externally to which a preloaded helical spring 25 is also applied, retained axially between an upper flange 21b of said upper part of the shutter body 21 and a lower washer 26 coupled to the same part (figures 7-8). The spring 25 is arranged so as to urge the shutter 21 against rotation towards a rest position. A first end 25a of the spring 25 is reacted against a stop 2b' (figures 7 and 8) provided inside the lower body part 2a, while the second end of the spring 25 is reacted on the shutter body 21. The shutter body 21 also has a radial extension 21c (figures 7 and 8), intended to abut against the cited stop 2a' in the rest condition of the shutter body 21 (the radial extension 21c can also function as an abutment for the cited second end of the spring 25).

[0086] The shutter body 21 further comprises a sealing ring or gasket 2 Id, intended to abut against a second valve seat 22a defined at the upper end of the valve body 22, when the shutter 21 closes the liquid passage.

[0087] The valve body 22 is substantially cylindrical, axially hollow, and mounted in a sealed manner, via an annular gasket 27, within the outlet 4 of the housing body of valve 1. The valve body 22 has a central guide portion 22b, substantially cylindrical, within which a substantially cylindrical lower part 2T of the shutter 21 is susceptible to slide, from which the corresponding lower head 21a extends downward.

[0088] The through cavity of the central guide portion 22b of the valve body 22 presents a radial and axial recess 22b', within which a corresponding radial and axial protrusion 21a' of the lower part 2 T of the shutter body 21 can be slidably engaged (see in particular figure 8).

[0089] In the valve 1, the shaft 11, the worm screw 16 with the associated reduction mechanism 17-18, the pinion 23 and the lamellar spring 24 obtains a mechanical flow metering arrangement, configured to cause, when needed, the switching of a mechanical valve arrangement, represented by the shutter body 21, the valve body 22 and the torsion spring 25, which operate as described below.

[0090] In the absence of a liquid flow, as shown in figures 7-9, the first shutter 10 and the shaft 11 are in a raised position, and the protrusion 21a' of the lower part 2 T of the shutter body 21 is located at a height higher than the recess 22b' of the valve body 22, outside it, not aligned therewith.

[0091] Suppose that the inlet 3 of the safety valve 1 is connected to a tap of a waternetwork, and that a supply pipe of a household appliance is associated with the outlet 4 of the safety valve.

[0092] In normal operation, the water entering the safety valve 1 causes the opening of the first shutter 10 relative to the first valve seat 13, as shown in figures 10-11. The water can reach the deflector 10a and then the diffuser 14. The water is then directed by the diffuser 14 onto the underlying impeller 15, which is set into rotation, with its number of revolutions being directly proportional to the liquid flow rate. In this condition, the lower end of the protrusion 21a' of the shutter body 21 rests on the upper edge of the central guide portion 22a of the valve body 22.

[0093] The impeller 15, through the associated worm screw 16 and the reduction mechanism 17-18, sets the pinion 23 into slow rotation which, in addition to rotating coaxially with the impeller 15, has moved downward together with the shaft 11 under the thrust that the first shutter 10 receives from the liquid. In this way, the front toothing 23a of the pinion 23 torsionally engages with the lamellar spring 24 which, loaded, sets the shutter body 21, integral with the same spring 24, into slow rotation, opposing the action of the spring 25, which therefore progressively loads. The water can flow out through the outlet 4 of the safety valve 1, i.e., through the valve body 22, since the shutter body 21 is in the open position, and reach the appliance via the corresponding supply pipe.

[0094] Upon cessation of the water flow, for example due to the closure of an internal solenoid valve of the appliance, if the volume of water released through the safety valve 1 falls within the preset field (i.e., is less than a safety limit preset for the valve itself), the pressure on the first shutter 10 ceases. The spring 12 therefore returns the axial shaft 11 and the first shutter 10 to closure of the respective valve seat 13. Consequently, the front toothing 23a of the pinion 23 releases the lamellar spring 24, and the spring 25, which had partially loaded due to the rotation of the shutter body 21, returns the shutter body 21 to the original angular position, with the previously mentioned radial protrusion 21a' of the shutter body against the related stop 2b', in a rest condition.

[0095] If, on the contrary, the incoming liquid flow does not stop, for example due to a break in the open position of said internal solenoid valve of the appliance or due to a pipe leak, the rotation of the shutter body 21 continues until the protrusion 21a' of the lower part 2T of the shutter 21 is aligned with the related recess 22b' of the central portion 22b of the valve body 22. At this point, the reaction of the spring 12 pushes the shutter body21 downward, so that its protrusion 21a' slips inside the recess 22b'. The shutter body 21 therefore moves downward, with the corresponding gasket 21d coming into contact with the valve seat 22a, thus preventing further liquid from exiting the valve 1. The head 21a of the shutter body 21 protrudes downward to a substantial extent with respect to the central portion 22b of the valve body 22, as shown in figures 10-11.

[0096] In order to restore the operability of the safety valve 1, the tap to which the safety valve 1 is attached may be closed, and the supply pipe of the appliance is disconnected from the outlet 4 of the same valve. Through the same outlet 4, an upward pressure must be exerted on the lower head 21a of the shutter 21, sufficient to overcome the reaction of the spring 12 and the pressure of the liquid acting from above on the shutter body 21. This pressure substantially corresponds to that existing in the supply water network, given that, in this condition, the first shutter 10 is still in the open position relative to the first valve seat 13.

[0097] The lifting of the shutter body 21 as a whole must be such as to cause the extraction of the protrusion 21a' of the lower part 2T of the shutter 21 from the related recess 22b' of the central portion 22b of the valve body 22, so that the reaction of the spring 25, previously loaded, causes the rotation of the same shutter body 21, returning it towards the original rest position of figures 7-9, in which said protrusion 21a' is not aligned with the related recess 22b'.

[0098] As explained in the introductory part, the reset operation is typically performed with a screwdriver or similar, and is relatively delicate, given that the internal components of the safety valve, such as its valve arrangement, are made of plastic material. In order to make this reset operation safer and more practical, the reset device 50 according to the invention is proposed.

[0099] For the purpose of occasional use of the device 50, after closing the tap upstream of the safety valve 1 and disconnecting the appliance supply pipe from the outlet 4 of the safety valve 1, the inlet fitting 52a of the device 50 is coupled to the same outlet 4, as shown in figures 12-14 (note that, in these figures, the shutter body 21 of the safety valve 1 is shown in the rest or open position, only for descriptive clarity).

[0100] It should be emphasized that the valve 1 might also be used to repeatedly deliver determined quantities of liquid, automatically closing upon reaching the predefined volume for the valve's intervention: consider, for example, a valve 1 used for irrigation,where a predefined volume of water must be directed to a generic crop. In applications of this type for the valve 1, where there is a cyclic need to restore the operability of the valve itself, the reset device 50 can be stably coupled between the valve 1 and the downstream (irrigation) pipe, for example mounted during the installation of the same valve (and therefore with the shutter body 21 of the safety valve 1 in the rest or open position, as in figures 12-14), in order to allow the reset operation to be performed cyclically without having to disconnect the downstream pipe each time. As can be seen, in this configuration the device 50 remains stably interposed between the safety valve 1 and the downstream pipe or other connection, continuing to make the reset function available without the need for further disassembly, where the intermediate placement of device 50 between the valve and the downstream line makes it possible to combine in a single component a fluid connection function and a mechanical reset function.

[0101] As noted in figures 12-14, in the mounted condition of the device 50, the central pin 76a of the corresponding reset member 76 is axially aligned with the head 21a of the shutter body 21 of the safety valve 1, in particular so as to allow transmission of the reset thrust along a direction substantially coinciding with the axis X. As can be seen, the device 50 is therefore configured so that its own movable element, constituted by the reset member 76, acts mechanically on a movable element of the associated safety valve.

[0102] In the initial condition, as already explained, the rear projection 77b' of the flange formation 77b of the rotatable member 77 of the device 50 is held in abutment by the spring 81 against the stop formation 70b of the lower body part 10 (see figures 3-5). The rotatable member 77 is therefore in an angular position such that the cam 78 associated with the shaft 77a is in a lowered rest position, or substantially disposed transversely (like 9 o'clock, looking frontally at the knob 77b-77c) with respect to the central pin 76a of the reset member 76, which therefore rests on an initial section of the corresponding cam surface 78d', as shown in figures 12-14. The reset member 76 is therefore in a lowered condition, completely contained within the portion of the duct C defined by the lower body part 70 of the device 50.

[0103] Figures 15 and 16 show an initial phase of the rotation manually imparted to the rotatable member 77. In these figures, the safety valve 1 is shown with its corresponding shutter body 21 in a closed position, and therefore with its corresponding head portion 21a in a lowered position.In the condition shown, the partial rotation of the rotatable member determines a corresponding angular movement of the cam 78, with a consequent initial sliding of the lower end of the pin 76a of the reset member 76 on the cam surface 78d'. The pin 76 of the reset member 76 therefore comes into contact with the lower end of the head portion 21a of the shutter body 21 of the safety valve 1. As can be seen, the movement of the reset member 76 does not end in an action internal to the device 50, but is functionally directed to transfer a reset thrust to the valve 1 aimed at returning the shutter thereof towards a stable open condition.

[0104] Figures 17 and 18 instead show the condition of maximum rotation of the rotatable member 77, to which there corresponds the completely raised position of the cam 78 (like 12 o'clock, looking frontally at the knob 77b-77c). As can be understood, during the passage from the position of figures 15-16 to that of figures 17-18, the lower end of the pin 76a of the reset member 76 progressively slides on the surface 78d' of the cam 78, up to the condition of maximum lifting of the member 76, which now partially protrudes into the portion of the duct C defined by the upper body part 60 of the device 50. In this phase, the central pin 76a of the member 76 determines the lifting of the head 21a of the shutter body 21 of the safety valve 1, up to the reset position wherein, as explained previously in relation for example to figures 7-9, the protrusion 21a' of the lower portion 21' of the shutter 21 disengages from the related recess 22b' of the central part 22b of the valve body 22, and the reaction of the spring 25 causes the rotation of the same shutter body, returning it towards the original position, wherein said protrusion 21a' is not aligned with the corresponding recess 22b'. As can be seen, the pin 76a of the reset member 76 is configured to cooperate with the movable element of the valve represented by the shutter body 21, in order to transmit a reset thrust in the axial direction.

[0105] The user can then release the rotatable member 77, so that the same is returned by its corresponding spring 81 to the initial position of figures 12-14, and the reset member 76 can descend again. The safety valve 1 is therefore reset, and the water still contained therein can flow into the supply pipe of the appliance (or other system).

[0106] In the case of the aforementioned occasional use of the device 50, the supply pipe of the appliance can then be detached from the outlet fitting 53 of the device 50, to be coupled again to the outlet 4 of the safety valve 1. The upstream tap can be reopened if necessary. Note that, in case of occasional reset of the valve 1, the connection of the citedsupply pipe to the outlet of the reset device 50 is not strictly indispensable. In the case of the aforementioned cyclic or repetitive use of the device 50, the user is not required to perform any additional operation beyond the manual rotation of the rotatable member 77, the device 50 being stably interconnected between the valve 1 and the downstream pipe.

[0107] In figures 19-21, a different version of a reset device aimed at facilitating the operation traditionally performed by a specialized technician is schematically illustrated, as an alternative to the operation of lifting via a relatively thin tool, such as a screwdriver, the shutter body 21 of a safety valve 1 of the type previously described.

[0108] In the different version shown in figures 19-21, the device indicated overall with 100 has a device body 101 in a single piece of molded plastic material, defining an inlet 102 and an outlet 103 at respective fittings having female and male threads, respectively, offset from each other and between which an internal duct C extends. The axes of the inlet 102 and the outlet 103 are designated by Xi and X2, respectively, in figures 19 and 21.

[0109] The body 101 defines a tubular sliding seat 104 external to the duct C, which is axially aligned relative to the center of the inlet 102. In an axially aligned position below the tubular seat 104, a guide recess 105 is defined, which in the example also extends at the thread of the outlet 103.

[0110] In the tubular seat 104, a reset pin 106, also of molded plastic material, is partially inserted, which has a upper head 106a and an operable lower portion 106b, like a linearly movable button. The reset pin 106 is predominantly located outside the duct C where the liquid flows, i.e., located partly in the tubular body portion 104 which is in hydraulic communication with the duct C but not affected by the liquid flow, given the presence of sealing means.

[0111] In an intermediate zone of the pin 106, an annular seat 106c for a sealing ring 107 is defined. A cylindrical part of the pin 106 extending above the seat 106c has a reduced diameter, so that a helical spring 108 can be fitted thereon, susceptible to being housed inside the tubular seat 104. In the lower part of the pin 106, just above the operable portion 106, a transverse through hole 106d is defined, for receiving a corresponding transverse pin 109. In the assembled condition, the ends of the pin 109 protrude relative to the pin 106, and are received slidably linearly in respective linear guides 110, arranged along axes parallel to the axis Xi, which extend laterally relative to the mouth of the tubularseat 104 and the terminal part of the underlying guide recess 105.

[0112] As can be understood, in the assembled condition, the pin 106, with the sealing ring 107 and the spring 108 on it, is constrained within the seat 104 and the recess 105, without the possibility of slipping out thanks to the engagement of the protruding ends of the pin 109 within the corresponding linear guides 110.

[0113] In the inlet 102 of the body 101, an annular stop element 111 is constrained, against which the upper end of the spring 108 abuts. At a seat 11 la of the annular stop element 111, a sealing gasket 112 is mounted. As can be understood, the reaction of the spring 108 against the stop element 111 maintains the pin 106 in a lowered position, wherein the protruding ends are at the lower bottom of the corresponding guides 110.

[0114] In figure 21, the device 100 is associated with a safety valve 1 of the type previously described. Also in this case, the inlet 102 of the device 100 is coupled to the outlet 4 of the valve 1, while a generic pipe can be coupled to the outlet 103 of the device 100. Note that also in figure 21, the shutter body 21 of the valve 1 is represented in a raised position.

[0115] As can be noted, in this condition, the upper end 106a of the reset pin 106 is axially aligned below the head 21a of the shutter body 21 of the valve 1. Therefore, for the purpose of resetting, the user need only to push the pin 106 linearly upward, acting on its operable portion 106b, like an axially movable button. In this way, when the pin 160 has been lifted for the maximum stroke thereof (determined by the abutment of the protruding ends of the pin 109 against the upper bottom of the corresponding guides 110), the shutter body 21 of the valve 1 has also been correspondingly lifted to an extent sufficient to determine the reset of the valve 1, similarly to what was previously described.

[0116] In the version of the device in figures 19-21, in order to have a slidable pin 106 that is axially aligned relative to the center of the inlet 102 (i.e., to the head 21a of the shutter body 21 of valve 1), it is necessary to shape the device body 101 with the inlet 102 and the outlet 103 not axially aligned, so as to have the necessary space for defining the tubular seat 104 for the pin 106. This inevitably results in a certain lateral or radial bulk of the reset device 100 as a whole, which is poorly compatible with certain possible uses (for example when the safety valve 1 is mounted in tight spaces, or on short taps). This drawback is not present in the case of the device 50 according to the invention, thanks to the coaxiality between the respective inlet fitting 52a and outlet fitting 53a,which reduces its bulk and facilitates liquid flow.

[0117] The fact that in the version of figures 19-21 the fitting comprising the inlet 102 is in one piece with the entire device body 101 presents evident advantages in terms of cost containment. However, in practice, this construction requires that the entire device body 101 be rotated for performing the coupling and decoupling operations with respect to the valve 1, and this is inconvenient, considering the aforementioned lateral or radial bulk of said body 101. The drawback is complicated by the fact that, at the end of coupling the device 100 to the valve 1, the angular orientation of the device itself is uncertain, and potentially in a position not favorable for operating the reset pin 106, or with the offset portion of the fitting 103 hitting a wall or other surrounding parts, not allowing or making the fixing of the outlet pipe inconvenient.

[0118] This angular orientation depends on the screwing position of the device 100, typically variable considering the need to compress both the axial sealing gasket 112 of the device 100 with respect to the outlet 4 of the valve 1 (see figure 21), and the axial sealing gasket 8 of the valve 1 with respect to the wall-mounted tap.

[0119] These drawbacks are not present in the case of the device 50 according to the invention, thanks to the axial shape of the device body 51, which has less bulk and facilitates liquid flow, and to the separate construction of the upper body part 60, which is freely rotatable and thus constitutes a rotatable fixing ring nut, which allows orienting the handle portion 77b, 77c of the rotatable member 77 in the position considered most favorable in relation to its maneuverability and the available surrounding spaces.

[0120] The fact that in the solution of figures 19-21 the reset member is represented by a simple push-button pin 106 slidable vertically simplifies the construction of device 100. However, with such a construction the linear movement occurs with a 1 : 1 ratio for the entire stroke of the pin 106, thereby requiring a considerable actuation effort at the start of the movement, due to the static water pressure that keeps the shutter body 21 of the safety valve 1 closed. In contrast, in the reset device 50 according to the invention, the reset action occurs by rotating the handle represented by portions 77b and 77c of the rotatable member 77, which rotates the transverse shaft 77a which in turn causes the angular movement of the cam 78, with the consequent lifting of the reset member 76 and therefore of the shutter body 21 of the safety valve 1. The mechanism obtained by the shaft 77a, the cam 78 and the reset member 76 can therefore be dimensioned to achievea very favorable ratio between the force applied to the aforesaid handle and that discharged onto the head 21a of the shutter body 21 of valve 1, greater than 1:1 and preferably between 1:4 and 1:8, for example approximately 1:6. This favorable ratio is particularly advantageous at the start of the reset movement, when maximum effort is required to cause the lifting of the shutter body 21 of valve 1, with this effort reducing gradually up to the maximum rotation of 90°, when high effort is no longer required because the water pressure has now decreased. This favorable ratio therefore allows easy manual reset, without the need for additional tools.

[0121] The shaft 77a of the device 50 according to the invention is also arranged transversely, substantially orthogonal to the axis of duct C (corresponding to the direction of the water flow) and therefore also occupies less space in that direction. The at least one sealing ring 80 mounted on the shaft 77a prevents water leakage, but at the same time allows its easy rotation without great effort: friction being generated on the internal diameter of the at least one ring 80, and not on the external diameter of the ring 107 as instead occurs in the version of figures 19-21, where the ring must also slide in a sealed manner along the internal surface of the tubular guide 104.

[0122] From the description provided, the characteristics of the present invention are clear. The invention allows having a specific reset device applicable as needed to a safety valve of the indicated type, of simple and economical construction, but of simple and effective use, with the advantages previously highlighted.

[0123] It is clear that numerous variants are possible for a person skilled in the art to the reset device described as an example, without thereby departing from the scope of the invention as defined by the claims that follow.

Claims

CLAIMS1. A reset device (50) for a safety valve (1), the device (50) having a device body (51) with an inlet (52) and an outlet (53) between which a duct (C) extends in an axial direction, the inlet (52) and the outlet (53) having an inlet fitting (52a) and an outlet fitting (53a), respectively, the inlet fitting (52a) and the outlet fitting (53a) being in particular configured to be coupled with an outlet of a safety valve (1) and a generic pipe, respectively, such that the reset device (50) is configured to be interposed between the outlet of the safety valve (1) and the generic pipe,wherein a reset mechanism (76-78) is mounted on the device body (51), which comprises:- a reset member (76) inside the duct (C), mounted for sliding in the axial direction between an inoperative position and an operative position,- an actuating member (77, 78), which is operable to cause displacement of the reset member (76) between the inoperative position and the operative position, wherein the actuating member (77, 78) includes:- a shaft (77a) extending inside the duct (C) transversely with respect to the axial direction, the shaft (77) being angularly rotatable below the reset member (76) in a corresponding seat (79, 82, 83) defined by the device body (51),- a cam (78) fixed in rotation on the shaft (77a), having a surface (78d') capable of interacting with a surface of the reset member (76) during a rotation of the shaft (77a), in order to move the reset member (76) at least from the inoperative position to the operative position, thereby causing in particular a lifting of a shutter body (21) of the safety valve (1).

2. The reset device (50) according to claim 1, wherein the device body (51) comprises at least a first body part (60) and a second body part (70) which are generally tubular in shape, coupled axially to each other, wherein the first body part (60) includes the inlet fitting (52a), and the second body part (70) includes the outlet fitting (53a) and has the reset mechanism (76-78) mounted thereon.

3. The reset device (50) according to claim 2, wherein the first body part (60) iscoupled to the second body part (70) in such a way as to rotate or perform angular movements with respect to the second body part (70) around an axis (X) of the duct (C), the first body part (60) preferably being coupled to the second body part (70) via a snap coupling or a quick coupling.

4. The reset device (50) according to any one of claims 1-3, wherein the device body (51) comprises at least one fastening or positioning element (Ci) for the reset member (76), preferably configured to prevent the reset member (76) from slipping out through the inlet fitting (52a).

5. The reset device (50) according to any one of claims 1-4, wherein:- the device body (51) defines, within the duct (C), positioning elements (82, 83) configured to hold the cam (78) in a substantially predefined position along the shaft (77a), and / or- the actuating member (77, 78) and the device body (51) are configured to prevent unintentional slipping out of the former from the latter, wherein preferably the shaft (77a) of the actuating member (77, 78) has at least one protrusion (77a1), and an upstream part (82) of the seat (79, 82, 83) form the shaft (77a) has at least one groove (82a) configured for enabling passage of the at least one protrusion (77a1) only during an assembly step of the reset device (50), the shaft (77a) being rotatable between the inoperative position and the operative position within an angular range which does not include an angular position at which the at least one protrusion (77a1) is axially aligned with the at least one groove (82a).

6. The reset device (50) according to any one of claims 1-4, wherein the device body (51) defines, within the duct (C), tubular positioning elements (82, 83) which obtains at least part of the seat (79, 82, 83) in which the actuating member (77) is angularly rotatable.

7. The reset device (50) according to any one of claims 1-6, wherein the inlet (52) and the outlet (53) of the device body (51) are substantially coaxial with each other.

8. The reset device (50) according to any one of claims 1-7, wherein the inlet fitting (52a) and the outlet fitting (53a) are complementary to each other, preferably comprising a female thread and a male thread complementary to each other.

9. The reset device (50) according to any one of claims 1-8, wherein the actuating member (77) has a manually graspable end portion which is arranged outside the duct (C) and is formed in a single piece with the shaft (77a).

10. The reset device (50) according to any one of claims 1-9, wherein the reset member (76) has a central reset pin (76a) which extends substantially according to the axis (X) of the duct (C) and has means for guiding and / or positioning and / or constraining (76b, 76c) with respect to the duct (C) associated thereto.

11. The reset device (50) according to claim 10, wherein the means for guiding and / or positioning and / or constraining means (76b, 76c) comprise at least one of:- a plurality of elements (76c) that extend radially from the central pin (76a), each having an outer surface or edge which faces or is slidably engaged with an inner circumferential surface of the duct (C);- an annular peripheral portion (76b) connected coaxially to the central reset pin (76a), in particular via a plurality of radial elements (76c), the peripheral annular portion (76b) having an outer circumferential surface slidably engaged with an inner circumferential surface of the duct (C), the outer circumferential surface of the annular peripheral portion (76b) having a height equal to a fraction of a height of the central reset pin (76a).

12. The reset device (50) according to claim 9, wherein the shaft (77a), the cam (78) and the reset member (76) are sized such that a ratio between a manual force applied to the graspable end portion of the shaft (77a) and a consequent thrust force generated by a displacement of the reset member (76) from the inoperative position to the operative position is greater than 1 : 1, in particular between 1 :4 and 1:8.

13. A reset device (50) for a safety valve (1) having a valve arrangement (21, 22,25), the reset device (50) having a device body (51) with an inlet (52) and an outlet (53) between which a duct (C) extends in an axial direction, the inlet (52) and the outlet (53) being designed for connection with an outlet of the safety valve (1) and a generic pipe, respectively,wherein a reset mechanism (76-78) is mounted on the device body (51), which comprises a reset member (76) inside the duct (C), mounted for sliding in the axial direction between an inoperative position and an operative position, and an actuating member (77, 78), operable to cause displacement of the reset member (76) at least from the inoperative position to the operative position, wherein displacement of the reset member (76) is adapted to transmit an axial thrust to a shutter body (21) of the valve arrangement (21, 22, 25) of the safety valve (1) when coupled to the inlet (52) of the reset device (50).

14. Use of a reset device (50) in accordance with one or more of claims 1-13 for resetting a valve (1) having a respective valve body (2) with an inlet (3) and an outlet (4), between which a respective valve duct for the passage of a liquid extends, within which a valve arrangement (21, 22, 25) is housed, configured to cause a condition of stable closure of the valve duct, preferably following passage through the safety valve (1) of a volume of liquid exceeding a determined threshold, a switching of the valve arrangement (21, 22, 25) causing displacement of a corresponding shutter body (21) from an open position to a closed position with respect to a valve seat (22a), with an axial element (21a) of the valve arrangement (21, 22, 25) which consequently protrudes into the outlet (4), wherein, with the inlet fitting (52) of the reset device (50) coupled to the outlet (4) of the safety valve (1), a rotation imparted manually to the actuating member (77) of the reset device (50) causes an axial movement of the corresponding reset member (76) inside the duct (C) of the device body (51), such as to cause a thrust on said axial element (21a) and a consequent displacement of the shutter body (21) of the valve arrangement (21, 22, 25) of the safety valve (1) into a condition of stable opening.

15. A combination comprising:a reset device (50) according to one or more of claims 1-13, anda safety valve (1) having a respective valve body (2) with an inlet (3) and an outlet(4), between which a respective valve duct for passage of a liquid extends, within which a valve arrangement (21, 22, 25) is housed, configured to cause a condition of stable closure of the valve duct , preferably following passage through the safety valve (1) of a volume of liquid exceeding a determined threshold, switching of the valve arrangement (21, 22, 25) causing displacement of a corresponding shutter body (21) from an open position to a closed position with respect to a valve seat (22a),wherein the inlet fitting (52) of the reset device (50) is coupled to the outlet (4) of the safety valve (1), and a rotation imparted manually to the actuating member (77) of the reset device (50) causes an axial displacement of the corresponding reset member (76) inside the duct (C) of the device body (51), such as to cause displacement of the shutter body (21) of the valve arrangement (21, 22, 25) of the safety valve (1) into a condition of stable opening.

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