Heat exchange apparatus for working fluids in power machines

Abstract

A heat exchange apparatus for working fluids in power machines, including a portion of hydraulic circuit within which the working fluid is adapted to flow, in this hydraulic circuit portion the following being provided: - a radiator, including o a radiator inlet, for the working fluid to enter the radiator, o an outlet, for the working fluid to exit the radiator, o a heat dissipation path for the fluid between the inlet and the outlet, - a fluid discharge path adapted to bypass the heat dissipation path, - a pilotable valve, arranged upstream of the dissipation path and the discharge path, adapted to manage the flow of the working fluid between the fluid discharge path and the heat dissipation path, - an electronic control module, operationally connected to the pilotable valve and configured to pilot the pilotable valve so that the working fluid, depending on the piloting imposed by the electronic control module, is adapted to pass through  only the heat dissipation path, or  the fluid discharge path, at least partially. With this configuration, it is possible, with a single valve device built into the radiator, to bypass on command the heat dissipation channels according to a desired logic of fluid flow management provided in the electronic control module, sending a certain quantity of working fluid, when needed, to the radiator outlet, thus being able, for example, to anticipate the pressure peaks, to optimize the thermal power, to manage radiator temperatures, etc.

Description

HEAT EXCHANGE APPARATUS FOR WORKING FLUIDS IN POWER MACHINESDescriptionTechnical Field

[0001] The present invention relates to the field of radiators in power machines for cooling the working fluid of the machines; more particularly, the object of the invention is a heat exchange apparatus for working fluids in power machines equipped with radiators, which is capable of optimizing the heat exchange in the radiator, and of enabling particularly durable radiators.State of the Art

[0002] In power machines, such as agricultural machines, earth moving machines, mechanical booms, etc., a power hydraulic circuit is provided, which is used, for example, to drive hydraulic actuators such as pistons or the like.

[0003] Oil is generally used as the working fluid in these power hydraulic circuits. During operation, the oil tends to heat up. In order to ensure the mechanical properties, it is necessary to keep the oil within a certain temperature range, and for these reasons a cooling radiator is inserted in the hydraulic circuit.

[0004] Usually, the radiator is of the oil / air type, and comprises a metal body provided with an oil inlet and an oil outlet, and a series of internal channels usually equipped with turbulators and finned externally, which allow heat exchange with the outside air. The radiator is often associated with a fan that forces cooling air through it.

[0005] During operation, in the oil working circuit, in addition to the pressure drops that can be generated also by the turbulators, instantaneous overpressure peaks can occur, for example, due to sudden actuations of machine members (e.g., due to strong depressurization of the system during the control release phases).

[0006] These pressure drops are also a function of the oil operating temperature. In early working conditions, the oil can be particularly cold. Low-temperature oil can have very high viscosity that increases the risks of overpressure.

[0007] To limit the pressure inside the radiator (resulting from the pressure drops and the overpressure peaks) and to prevent damage thereof, an overpressure protection bypass valve is provided in the radiator allowing the pressurized oil to be discharged toward a discharge area (devoid of turbulators and properly sized), from which it can be fed back into the main hydraulic circuit.

[0008] The overpressure bypass valve is basically a mechanical valve so arranged as to close a bypass passage of the oil from the oil path in the radiator, for the purpose of cooling, to an oil discharge segment in a lower pressure zone. This valve is either open or closed, depending on the pressure in the radiator. When open, i.e., when overpressure is reached, the valve allows the oil to flow through the bypass passage toward the discharge segment. When the valve is closed, that is, when the pressure in the radiator is below the overpressure limit value, the oil in the radiator circulates normally without being discharged to the discharge segment.

[0009] In general, the overpressure bypass valve includes a shutting member that closes the bypass passage, which is kept in closed position by an elastic spring, appropriately calibrated to the overpressure limit value.

[0010] In other solutions, a second separate bypass valve is associated with the radiator for discharging oil, depending on the temperature thereof. In this case, the respective shutting member that opens or closes the valve toward an oil discharge segment is moved by a special device provided with a temperature-sensitive material that mechanically expands and actuates the valve depending on the oil temperature.

[0011] Radiators provided with these types of valves have been known and appreciated by the market for many years now, but they are not free from perfectibility.

[0012] Improvements in the radiators aim, for example, at optimizing the oil flow in order to improve the heat exchange based on the machine cycle, reducing overall dimensions, increasing radiator safety, reducing radiator weight, reducing or eliminating external connections, etc.Summary

[0013] The aim of the present invention is to identify improvements to power machine radiator systems that meet the needs highlighted above.

[0014] Within this aim, an important object of the present invention is to provide a heat exchange apparatus for working fluids in power machines, in which different functions are implemented for managing the working fluid.

[0015] A further important object of the invention is to provide a heat exchange apparatus for working fluids in power machines, which is flexible in use.

[0016] One more important object of the invention is to provide a heat exchange apparatus for working fluids in power machines, which is equipped with a radiator and is particularly reliable in operation, practically allowing to reduce or to eliminate the risks due to overpressure and thus enabling the design of radiators of reduced thickness.

[0017] A further important object of the invention is to provide a heat exchange apparatus for working fluids in power machines, which is equipped with a radiator and reduces the space required for the use of external valves in radiators.

[0018] These and other objects, that will become clearer later, are achieved through a heat exchange apparatus for working fluids in power machines, including a portion of hydraulic circuit within which the working fluid is adapted to flow, in this hydraulic circuit portion being provided: a radiator, including• a radiator inlet, for the working fluid to enter the radiator,• an outlet, for the working fluid to exit the radiator,• a heat dissipation path for the fluid between the inlet and the outlet, a fluid discharge path adapted to bypass the heat dissipation path, a pilotable valve, arranged upstream of the dissipation path and the discharge path, adapted to manage the flow of the working fluid between the fluid discharge path and the heat dissipation path, an electronic control module, operationally connected to the pilotable valve and configured to pilot the pilotable valve so that the working fluid, depending on the piloting imposed by the control unit, is adapted to pass through• only the heat dissipation path, or• the fluid discharge path, at least partially.

[0019] In practice, in this way, it is possible, with a single valve device associated with, and preferably built into, the radiator, to bypass the heat dissipation channels according to a desired logic of fluid flow management provided in the electronic control module, sending a certain quantity of working fluid, when needed, to the radiator outlet, thus being able, for example, to anticipate the pressure peaks, to optimize the thermal power, to manage radiator temperatures, etc.

[0020] The heat exchange apparatus preferably includes one or more of the following components: a motorized cooling fan for the radiator, operationally connected with the electronic control module, at least one temperature sensor, operationally connected with the electronic control module; preferably at least one first temperature sensor arranged upstream of the heat dissipation path and preferably at least one second temperature sensor arranged downstream of the heat dissipation path; at least one pressure sensor, operationally connected with the electronic control module, preferably at least one first pressure sensor arranged upstream of the heat dissipation path and preferably at least one second pressure sensor arranged downstream of the dissipation path; and wherein the electronic control module is configured to communicate with the above components.

[0021] In practice, in this way, in combination with the flow management through the pilotable valve, the complete operation of the heat exchange apparatus can be best managed, optimizing radiator temperatures and thermal power also based on the speed of the cooling fan.

[0022] Preferably, given a maximum working fluid flow rate through the heat dissipation path for the radiator, the electronic control module varies the flow rate between the maximum flow rate and a flow rate less than the maximum flow rate for a given time interval, by piloting the pilotable valve so that the pilotable valve discharges at least part of the fluid through the fluid discharge path.

[0023] According to preferred embodiments, the electronic control module provides for one or more of the following operation modes, related, for example, to radiator protection and low-temperature operation:- the electronic control module receives a signal about a possible pressure peak in the fluid entering the heat dissipation path, thus the electronic control module commands the pilotable valve to discharge at least part of the fluid through the fluid discharge path; for example, the electronic control module receives a high-pressure signal from a pressure sensor; thus, the electronic control module commands the pilotable valve to discharge at least part of the fluid through the fluid discharge path;- the electronic control module receives a signal about low temperature of the fluid entering the heat dissipation path; thus the electronic control module commands the pilotable valve to discharge at least part of the fluid through the fluid discharge path.

[0024] According to preferred embodiments, the electronic control module includes at least one communication port configured to be connected with an electronic unit, external to the heat exchange apparatus and belonging to the power machine with which the heat exchange apparatus is associated, the electronic control module being configured to receive signals from outside the apparatus and to process the signals to enable at least part of the operation of the apparatus. For example, an electronic management device can send signals to the electronic control module of the heat exchange apparatus concerning the opening of the pilotable valve so that it discharges at least part of the fluid through the discharge path, or even concerning change in the rotational speed of a radiator cooling fan, the indication of new thermal power values to be achieved by the radiator, new temperature values of the fluid entering / exiting the radiator, or other operation modes.

[0025] This makes it possible to manage at the best the thermal power of the radiator and, in general, the temperature of the working fluid in the power machine, with which the radiator is associated.

[0026] Preferably, a predetermined required thermal power level for the radiator is provided in the apparatus, which is substantially a function of the temperature difference and pressure difference between the first and the second temperature andpressure sensors; in the apparatus, some operation logics of the electronic control module provide for the electronic control module to calculate the temperature and pressure difference values and to calculate the radiator thermal power level; if the calculated thermal power level is different from the predetermined required thermal power level for the radiator, the electronic control module is so configured as a) to vary the temperature and / or pressure difference by varying the fluid flow rate through the heat dissipation path by acting on the pilotable valve, or b) to vary the temperature difference by acting on the speed of the radiator cooling fan, or c) appropriately to implement both solutions a and b.

[0027] According to preferred embodiments, in the apparatus, a first predetermined fluid temperature is provided upstream of the heat dissipation path and / or a second predetermined fluid temperature is provided downstream of the heat dissipation path; in the apparatus, some operation logics of the electronic control module provide for the electronic control module to calculate the values of the first and / or second temperature by means of the first and second temperature sensors, and, if the first and / or second temperature values differ from the first and / or second predetermined fluid temperature, the electronic control module is so configured as a) to vary the first and / or second temperature values by varying the fluid flow rate through the heat dissipation path by acting on the pilotable valve, or b) to vary the first and / or second temperature values by acting on the speed of the radiator cooling fan, or c) appropriately to implement both solutions a and b.

[0028] According to preferred embodiments, the pilotable valve is a two-way valve of the open / closed type adapted to close a discharge port to the fluid discharge path, and wherein the change in the flow rate through the heat dissipation path occurs by keeping the valve always open in the given time interval by the electronic control module, or by a train of subsequent open- closed pulses in the same time interval sent to the valve by the control unit, whereby the fraction of flow rate through the valve has a lower average value than the maximum flow rate achievable by keeping the valve always open;or a valve with at least three ways, wherein a first way is associated with the fluid entering the radiator, a second way is associated with a discharge port toward the heat dissipation path, and a third way is associated with the discharge port, so that, depending on the piloting of the valve, the fluid is directed• only towards the heat dissipation path,• only through the discharge port,• both towards the heat dissipation path and the discharge port; whereby the change in the flow rate through the heat dissipation path occurs by keeping the fluid directed toward both the heat dissipation path and the discharge port in the given time interval; preferably, the pilotable valve has a proportional pilot control, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal.

[0029] According to preferred embodiments, the radiator includes at least one portion of the fluid discharge path adapted to bypass the heat dissipation path, wherein the portion of the discharge path includes at least one first discharge port, adapted to provide access to the discharge path, and wherein the pilotable valve is adapted to divide the flow of the working fluid, coming from the radiator inlet, between the at least one discharge port toward the discharge path and the heat dissipation path, so that the working fluid, depending on the piloting of the valve, is adapted to pass through only the heat dissipation path, or- the at least one discharge port, so that the fluid is discharged at least partially into the discharge path.

[0030] According to preferred embodiments, the radiator comprises a first manifold, into which the fluid from the inlet enters, a plurality of heat dissipation channels, directly connected with the first manifold, through which the fluid from the first manifold flows, a second manifold, operatively connected with the plurality of heat dissipation channels, into which the fluid from the plurality of heat dissipation channels arrives;the radiator preferably including at least one deviation channel adapted to connect the first manifold and the second manifold, wherein the deviation channel is distinct from the heat dissipation channels.

[0031] According to preferred embodiments, the apparatus includes an overpressure protection unit of the mechanical type, arranged downstream of the radiator inlet and adapted to divide the flow of the working fluid from the inlet so that the working fluid is adapted to flow at least partially through the at least one first discharge port to be discharged at least partially into the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceeded.

[0032] According to preferred embodiments, between the radiator inlet and the heat dissipation path a branch is provided, in which there is the at least one portion of the fluid discharge path provided with a first discharge port, and wherein the pilotable valve is a two-way valve associated with the first discharge port without interrupting the flow of the fluid from the inlet to the heat dissipation path, so that, if the valve is piloted so as to be kept open, the fluid is adapted to pass simultaneously through- both the heat dissipation path and the first discharge port into the discharge path, while if the valve is piloted so as to be kept closed, the fluid is adapted to pass through only the heat dissipation path.

[0033] According to preferred embodiments, the pilotable valve comprises an overpressure protection unit of the mechanical type, comprising an intercepting assembly for intercepting the fluid passing through a first discharge port towards the fluid discharge path, the intercepting assembly comprising• a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the first discharge port, and at least one access position, adapted to allow the fluid to pass through the first discharge port, and• an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position;when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the discharge port, a pilot actuator, adapted to move the first shutting member between the shutting position and the access position against the resistance of the reversibly compressible device, allowing the fluid to pass through the first discharge port.

[0034] Preferably, only one first shutting member is provided, which is mechanically operated only by the fluid overpressure as an overpressure protection group, or it is piloted by the electronic control module to open / close the first discharge port.

[0035] According to preferred embodiment, the first discharge port ends into a deviation channel inside the radiator body, for bypassing the heat dissipation channels, which connects the manifolds, so that the at least one discharge port is adapted to allow the fluid to pass between the two radiator manifolds.

[0036] According to preferred embodiments, the pilotable valve comprises at least an overpressure protection unit of the mechanical type, comprising a first intercepting assembly for intercepting the fluid passing through a first discharge port towards the fluid discharge path, the first intercepting assembly comprising• a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the first discharge port, and at least one access position, adapted to allow the fluid to pass through the first discharge port, and• an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the first discharge port,a second intercepting assembly for intercepting the fluid passing through a second discharge port toward the fluid discharge path, including• a second shutting member movable from a closed position, adapted to close the passage of the fluid through the second discharge port, to an open position, adapted to allow the passage of the fluid through the second discharge port, and• a pilot actuator, adapted to move the second shutting member between the closed position and the open position, allowing the fluid to pass through the second intercepting assembly.

[0037] Preferably, the second valve shutting member is adapted to reversibly close a section defining the second discharge port, internal to the valve, where the fluid passes through the second intercepting assembly, so that the closed position relates to the closing of the fluid passage section and the open position relates to the consent for the passage of the fluid through the fluid passage section; the passage section is preferably provided in a cavity operatively connected with the outside of the valve in correspondence of the first manifold from which the flow of fluid to be blocked / allowed by the valve comes, wherein the second shutting member is movable according to an axial direction and includes a closing head, for closing the passage seat, and a face opposite the head, transverse to the axis of movement of the second shutting member, wherein the face is subject to the same pressure as the fluid in the cavity; preferably the second fluid intercepting assembly comprising a fluid access duct to the passage section, wherein the fluid access duct passes through the closing surface of the first shutting member; the second fluid intercepting assembly preferably including one or more discharge segments fluidly connected with the passage section and ending into a lateral portion of the valve body comprised between the closing surface and the passage section.

[0038] According to preferred embodiments, the valve comprises a liner defining an inner space, wherein the first shutting member is at least partially contained within the inner space of the liner.

[0039] According to preferred embodiments, the valve comprises a liner defining an inner space, wherein the liner has a fastening system for fastening to a seat in theradiator body, with which the valve shall be associated; the fastening system preferably includes a thread provided on the cylindrical outer surface of the liner.

[0040] Preferably, the valve includes a central axis, and the first shutting member is movable along the central axis; the first shutting member comprising a closing surface adapted to abut, when closing, against a stop.

[0041] Preferably, the pilot actuator includes a piston, configured to be controlled so as to move parallel to the central axis, adapted to act on the first shutting member; the first shutting member preferably comprising a base on which the closing surface is defined, a stem extending from the base, the stem having an interaction end for interacting with a gripping portion of the piston.

[0042] Preferably,- the liner has a first chamber open towards the shutting position of the first shutting member, the first shutting member is adapted to slide axially within the first chamber, with the closing surface remaining external to the first chamber,- the reversibly compressible device is of type axially compressible between two ends, wherein a first end is adapted to abut against the bottom of the first chamber, and a second end is adapted to abut against the first shutting member,

[0043] According to preferred embodiments, the radiator comprises a box-shaped body provided with a first and a second tray defining the first and the second manifolds and connected with each other by means of a plurality of dissipation channels mutually separated by finned surfaces; a metal disturbance warp is provided within each dissipation channel; the first tray includes, preferably at an end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has a first discharge port, which connects the compartment with the first tray, and at least one delivery port, which connects the deviation compartment with the at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly.

[0044] According to preferred embodiments, the pilotable valve is a valve with at least three ways, wherein a first way is associated with the radiator inlet for the working fluid to enter the radiator, a second way is associated with the heat dissipation path, and a third way is associated with the discharge port, so that, depending on the piloting of the valve, the fluid from the radiator inlet is directed only towards the heat dissipation path, only through the discharge port,- both towards the heat dissipation path and the discharge port.

[0045] Preferably, the pilotable valve includes a valve body provided with an inner compartment, on which are defined a first port associated with the radiator inlet, a second opening associated with the heat dissipation path, and a third opening associated with the discharge port, at least one shutting member that is movable in a shutting direction depending on the piloting of the valve, wherein, along the shutting direction, the shutting member is adapted to take positions• of complete shutting of the second opening, with the third opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the second opening completely closed and to increase or to decrease the unclosed area of the third opening ,• of complete shutting of the third opening , with the second opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the third opening completely closed and to increase or to decrease the unclosed area of the second opening .

[0046] Preferably, the shutting direction is an axial direction and the shutting member has two opposite ends, a first piloting end, on which a pilot actuator acts for axially moving the shutting member in a first direction, and an opposite second end; preferably a return member, for returning the shutting member in a direction opposite to the first direction, abuts against the second end.

[0047] Preferably, the apparatus comprises an overpressure protection unit of a mechanical type arranged downstream of the inlet and adapted to divide the flow ofthe working fluid coming from the inlet so that the working fluid is adapted to flow at least partially through the discharge port to be discharged at least partially towards the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceed, the overpressure protection unit being formed by the part of the at least one shutting member adapted to close the discharge port and a reversibly compressible overpressure device, adapted to prevent the movement of the part of the at least one shutting member from the shutting position; when a given pressure of fluid against the part of the at least one shutting member is exceeded, the part is adapted to move from the shutting position to a position adapted to allow the fluid to pass through the discharge port, compressing the reversibly compressible device; the reversibly compressible device is preferably an elastic spring with predetermined elastic stiffness defining the mechanical calibration threshold.

[0048] Preferably, the valve comprises a pilot actuator adapted to act on the shutting member to enable its movement thereof along the shutting direction; the actuator being preferably a mechanical, electrical, pneumatic, or hydraulic actuator, or a combination thereof.

[0049] According to preferred embodiments, the apparatus comprises a box-shaped body provided with a first and a second tray defining the first and the second manifolds and connected with each other by means of a plurality of dissipation channels mutually separated by finned surfaces; a metal perturbation warp is preferably provided within each dissipation channel.

[0050] Preferably, the first tray includes, preferably at an end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has the first discharge port, which connects the compartment with the first tray, and at least one delivery port, which connects the deviation compartment with the at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly; the at least one deviation channel is preferably internal to the box-shaped body of the radiator.

[0051] Preferably, the at least one deviation channel is internal to the box-shaped body of the radiator, and wherein in the box-shaped body of the radiator a dischargecompartment is provided, adjacent to the first tray and separate from it, from which the deviation channel starts, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray and the discharge compartment, so that the second opening of the valve and the third opening of the valve are arranged at respective passages provided in the wall of the box-shaped body of the radiator for access to the tray and to the discharge compartment respectively.

[0052] According to preferred embodiments, the at least one deviation channel is internal to the box-shaped body of the radiator and the radiator outlet is provided along the at least one deviation channel.

[0053] Preferably, the at least one deviation channel is formed by a pipe external to the radiator, i.e. external to the box-shaped body of the radiator, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray, so that the second opening is arranged in correspondence of a respective passage for accessing the first tray, while the third opening is provided on a face not facing the box-shaped body of the radiator, in order to be connected to the external pipe.

[0054] Preferably, the pilotable valve has a proportional pilot control, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal.

[0055] According to preferred embodiments, a back-flow valve is provided between the second manifold and the radiator outlet.

[0056] According to a further aspect, the invention relates to a radiator including: a radiator inlet, for the working fluid to enter the radiator, an outlet, for the working fluid to exit the radiator, a heat dissipation path for the fluid between the radiator inlet and the outlet, at least one portion of the fluid discharge path adapted to bypass the heat dissipation path, wherein the portion of the fluid discharge path includes a discharge port, adapted to provide access to the discharge path,characterized by comprising a pilotable valve, adapted to divide the flow of the working fluid, coming from the radiator inlet, between the discharge port for accessing the discharge path and the dissipation path, so that the working fluid, depending on the piloting of the valve, is adapted to pass through only the heat dissipation path, or- the discharge port, so that the fluid is discharged at least partially into the discharge path.

[0057] In practice, in this way, it is possible, with a single valve device built into the radiator, to bypass on command the heat dissipation channels according to a desired logic of fluid flow management, sending a certain quantity of working fluid, when needed, to the radiator outlet, thus being able, for example, to anticipate the pressure peaks.

[0058] Preferably, the radiator is provided with a first manifold, into which the fluid from the inlet enters, a plurality of heat dissipation channels, directly connected with the first manifold, through which the fluid from the first manifold flows, a second manifold, operatively connected with the plurality of heat dissipation channels, into which the fluid from the plurality of heat dissipation channels arrives.

[0059] The radiator preferably includes at least one deviation channel adapted to connect the first manifold and the second manifold, wherein the deviation channel is distinct from the heat dissipation channels.

[0060] According to preferred embodiments, the radiator includes an overpressure protection unit of the mechanical type, arranged downstream of the radiator inlet and adapted to divide the flow of the working fluid from the inlet so that the working fluid is adapted to flow at least partially through the discharge port to be discharged at least partially into the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceeded.

[0061] Preferably, in the radiator, the overpressure protection unit is built into the pilotable valve.

[0062] According to preferred embodiments, in the radiator, between the inlet and the heat dissipation path a branch is provided, in which there is the at least one portion of the fluid discharge path provided with the discharge port, and wherein the pilotable valve is a two-way valve associated with the discharge port without interrupting the flow of the fluid from the inlet to the heat dissipation path, so that, if the valve is piloted so as to be kept open, the fluid is adapted to pass simultaneously through- both the heat dissipation path and the discharge port into the discharge path, while if the valve is piloted so as to be kept closed, the fluid is adapted to pass only through the heat dissipation path.

[0063] With this two-way configuration, the valve has a special compact appearance that can be built into the radiator box-shaped body, benefiting the overall dimensions.

[0064] According to preferred embodiments, in the radiator the pilotable valve comprises an overpressure protection unit of the mechanical type, comprising an intercepting assembly for intercepting the fluid passing through the discharge port towards the fluid discharge path, the intercepting assembly comprising• a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the discharge port, and at least one access position, adapted to allow the fluid to pass through the discharge port, and• an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the discharge port,a pilot actuator, adapted to move the first shutting member between the shutting position and the access position against the resistance of the reversibly compressible device, allowing the fluid to pass through the discharge port.

[0065] According to preferred embodiments, in the radiator the pilotable valve comprises an overpressure protection unit of the mechanical type, comprising a first intercepting assembly for intercepting the fluid passing through the discharge port towards the fluid discharge path, the first intercepting assembly comprising o a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the first discharge port, and at least one access position, adapted to allow the fluid to pass through the first discharge port, and o an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the first discharge port, a second intercepting assembly for intercepting the fluid passing through a second discharge port to the discharge path, including o a second shutting member movable from a closed position, adapted to close the passage of the fluid through the second discharge port, to an open position, adapted to allow the passage of the fluid through the second discharge port, and o a pilot actuator, adapted to move the second shutting member between the closed position and the open position, allowing the fluid to pass through the second intercepting assembly.

[0066] In the latter case, in practice, the first and second intercepting assemblies allow the fluid to pass through different and independent passages, so it is possible for the fluid to pass the valve through only the first intercepting assembly, or through only the second intercepting assembly, or through both.

[0067] For example, the first intercepting assembly is purely mechanical, and the closing movement of the first valve shutting member is allowed by the reversibly compressible device on the basis of a pressure value of the fluid entering the radiator higher than the overpressure value; whilst the second intercepting assembly is of the electromechanical type, and the movement of the second valve shutting member is realized by an electrically controlled actuator.

[0068] With such a configuration, it is therefore possible to have a radiator with a valve that essentially is a bypass valve, adapted to protect the radiator against pressures above a given limit pressure and, at the same time, to use this valve for further operations, such as opening or closing the valve depending on the fluid temperature, or even opening the valve when, on the basis of particular operations of the machine with which the radiator is associated, a pressure peak is expected, actually anticipating the operation of the mechanical overpressure protection unit. In addition, the correct quantity of oil in the radiant mass can be dosed according to the optimal temperature and pressure so as to maximize / optimize the heat transfer.

[0069] According to preferred embodiments, in the radiator the second valve shutting member is adapted to reversibly close a section, in practice the second discharge port, internal to the valve, where the fluid passes through the second intercepting assembly, so that the closed position relates to the closing of the fluid passage section and the open position relates to the consent for the passage of the fluid through the fluid passage section.

[0070] Preferably, in the radiator, the passage section is provided in a cavity operationally connected with the outside of the valve in correspondence of the room from which the fluid flow to be blocked / allowed by the valve comes; the second shutting member is movable according to an axial direction and includes a closing head, for closing the passage seat, and a face opposite the head, transverse to the axis of movement of the second shutting member, wherein the face is subject to the same pressure as the fluid in the cavity; An elastic compression element is preferably provided, adapted to act against that face.

[0071] Preferably, in the radiator, the second valve shutting member is adapted to close the second discharge port; preferably the second discharge port ends into adeviation channel inside the radiator body, for bypassing the heat dissipation channels, which connects the manifolds, so that the second discharge port is adapted to allow the fluid to pass between the two radiator manifolds.

[0072] According to preferred embodiments, in the radiator, the first shutting member is adapted to close a first discharge port which is defined in the radiator and is adapted to allow the passage of the fluid from the radiator inlet to the fluid discharge path.

[0073] In practice, according to preferred embodiments, in the radiator the valve blocks the flow between the two radiator rooms according to two independent modes: (1) by means of a movable closing surface of a first discharge port defined on the radiator, wherein the closing surface relates to a portion of the external surface of the valve, so that the fluid does not pass through the valve, (2) by means of closing (operated, for example, electrically) a passage section defining the second discharge port toward the discharge path internal to the valve, through which the fluid is adapted to circulate, and wherein, preferably, the fluid enters the valve toward the passage section through the closing surface and exits, preferably, through one or more discharge segments fluidly connected with the passage section and ending onto a lateral portion of the valve body between the closing surface and the passage section.

[0074] In preferred embodiments, in the radiator the valve comprises a liner defining an inner space, wherein the first shutting member is at least partially contained within the inner space of the liner.

[0075] In preferred embodiments, in the radiator the valve comprises a liner defining an inner space, wherein the fluid passage section of the second intercepting assembly is provided within the inner space.

[0076] According to preferred embodiments, in the radiator the valve comprises a liner defining an inner space, wherein the liner has a fastening system for fastening to a seat in the radiator body, with which the valve shall be associated; the fastening system preferably includes a thread provided on the cylindrical outer surface of the liner.

[0077] According to preferred embodiments, in the radiator the valve includes a central axis, and the first shutting member is movable along the central axis; the first shutting member comprises a closing surface adapted to abut, when closing, against a stop.

[0078] Preferably, in the radiator, the pilot actuator includes a piston, configured to be controlled so as to move parallel to the central axis, adapted to act on the first shutting member; the first shutting member preferably comprising a base on which the closing surface is defined, a stem extending from the base, the stem having an interaction end for interacting with a gripping portion of the piston.

[0079] According to preferred embodiments, in the radiator the second fluid intercepting assembly comprises a fluid access duct to the passage section, wherein the fluid access duct passes through the closing surface of the first shutting member.

[0080] Preferably, in the radiator, the liner has a first chamber open towards the shutting position of the first shutting member; the first shutting member is adapted to slide axially within the first chamber, with the closing surface remaining external to the first chamber; the reversibly compressible device is of type axially compressible between two ends, wherein a first end is adapted to abut against the bottom of the first chamber, and a second end is adapted to abut against the first shutting member, the fluid access duct towards the passage section of the second fluid intercepting assembly passes through the bottom; the fluid access duct is preferably provided within a tubular body projecting from the bottom of the first chamber and ending into the radiator through the closing surface of the first shutting member.

[0081] Preferably, the radiator comprises a box-shaped body provided with a first and a second tray defining the first and the second manifolds and connected with each other by means of a plurality of dissipation channels mutually separated by finned surfaces; a metal disturbance warp is provided within each dissipation channel; the first tray includes, preferably at an end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has the first discharge port, which connects the compartment with the first tray, and at least one delivery port, which connects the deviation compartment withthe at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly.

[0082] According to preferred embodiments of the radiator, the pilotable valve is a valve with at least three ways, wherein a first way is associated with the radiator inlet for the working fluid to enter the radiator, a second way is associated with the heat dissipation path, and a third way is associated with the discharge port, so that, depending on the piloting of the valve, the fluid from the radiator inlet is deviated only towards the heat dissipation path, only through the discharge port,- both towards the heat dissipation path and the discharge port.

[0083] Preferably, in the radiator the pilotable valve includes a valve body provided with an inner compartment, on which are defined a first opening associated with the radiator inlet, a second opening associated with the heat dissipation path, and a third opening associated with the discharge port, at least one shutting member that is movable in a shutting direction depending on the piloting of the valve, wherein, along the shutting direction, the shutting member is adapted to take positions o of complete shutting of the second opening, with the third opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the second opening completely closed and to increase or to decrease the unclosed area of the third opening , o of complete shutting of the third opening , with the second opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the third opening completely closed and to increase or to decrease the unclosed area of the second opening.

[0084] Preferably, the shutting direction is an axial direction and the shutting member has two opposite ends, a first piloting end, on which a pilot actuator acts foraxially moving the shutting member in a first direction, and an opposite second end; preferably a return member, for returning the shutting member in a direction opposite to the first direction, abuts against the second end.

[0085] Preferably, the radiator comprises an overpressure protection unit of a mechanical type arranged downstream of the inlet and adapted to divide the flow of the working fluid coming from the inlet so that the working fluid is adapted to flow at least partially through the discharge port to be discharged at least partially towards the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceed, the overpressure protection unit being formed by the part of the at least one shutting member adapted to close the discharge port and a reversibly compressible overpressure device, adapted to prevent the movement of the part of the at least one shutting member from the shutting position; when a given pressure of fluid against the part of the at least one shutting member is exceeded, the part is adapted to move from the shutting position to a position adapted to allow the fluid to pass through the discharge port, compressing the reversibly compressible device; the reversibly compressible device is preferably an elastic spring with predetermined elastic stiffness defining the mechanical calibration threshold.

[0086] Preferably, in the radiator, the valve comprises a pilot actuator adapted to act on the shutting member to enable its movement thereof along the shutting direction; the actuator is preferably a mechanical, electrical, pneumatic, or hydraulic actuator, or a combination thereof.

[0087] Preferably, the radiator comprises a box-shaped body provided with a first and a second tray defining the first and the second manifolds and connected with each other by means of a plurality of heat dissipation channels that are preferably mutually separated by finned surfaces; a metal perturbation warp is preferably provided within each dissipation channel.

[0088] Preferably, in the radiator the first tray includes, preferably at an end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has the first discharge port, which connects the compartment with the first tray, and at least one delivery port, whichconnects the deviation compartment with the at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly; the at least one deviation channel is preferably internal to the box-shaped body of the radiator.

[0089] Preferably, in the radiator, the at least one deviation channel is internal to the box-shaped body of the radiator, and wherein in the box-shaped body of the radiator a discharge compartment is provided, adjacent to the first tray and separate from it, from which the deviation channel starts, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray and the discharge compartment, so that the second opening of the valve and the third opening of the valve are arranged at respective passages provided in the wall of the box-shaped body of the radiator for access to the tray and to the discharge compartment respectively.

[0090] Preferably in the radiator, for both the first and second preferred embodiments, the at least one deviation channel is internal to the box-shaped body of the radiator and the radiator outlet is provided along the at least one deviation channel.

[0091] Preferably, in the radiator the at least one deviation channel is formed by a pipe external to the radiator, i.e. external to the box-shaped body of the radiator, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray, so that the second opening is arranged in correspondence of a respective passage for accessing the first tray, while the third opening is provided on a face not facing the box-shaped body of the radiator, in order to be connected to the external pipe.

[0092] Preferably, in the radiator the pilotable valve has a proportional pilot control, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal.

[0093] Preferably, in the radiator, for both the first and second preferred embodiments, a back-flow valve is provided between the second manifold and the radiator outlet. An accumulation system can be also provided to compensate for any delay in closing the back-flow valve.

[0094] According to a further aspect, a further object of the invention is a pilotable valve of the type configured to be inserted in the heat exchange apparatus according to one or more of the above-mentioned embodiments, wherein the pilotable valve comprises an overpressure protection unit of the mechanical type, comprising an intercepting assembly for intercepting the fluid passing through a discharge port towards the fluid discharge path, the intercepting assembly comprising o a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the discharge port, and at least one access position, adapted to allow the fluid to pass through the discharge port, and o an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the discharge port, a pilot actuator, adapted to move the first shutting member between the shutting position and the access position against the resistance of the reversibly compressible device, allowing the fluid to pass through the discharge port.Brief description of the drawing

[0095] The invention will be better understood by following the description below and the attached drawing, showing some non-limiting embodiments of the invention. More particularly, in the drawing:Fig. 1 is a schematic axonometric view of a radiator usable in a heat exchange apparatus for working fluids in power machines, according to a first embodiment of the invention, cut-away according to a vertical longitudinal plane, in an arrangement where a two-way bypass valve is fully closed;Fig. 2 is a top view of a two-way bypass valve, associated with a radiator portion in a heat exchange apparatus for working fluids in power machines, according to a firstembodiment of the invention, cut-away according to a plane passing approximately through the axis of the valve, in an arrangement where the valve is fully closed;Fig. 3 is a schematic side view of the valve of Fig. 2, associated with a radiator portion in a heat exchange apparatus for working fluids in power machines, according to the first embodiment of the invention, cut-away according to a vertical longitudinal plane passing approximately through the axis of the valve, in an arrangement where the first intercepting assembly is open, i.e., allows the fluid to pass, and the second intercepting assembly is closed, i.e., does not allow the fluid to pass;Fig. 4 is a schematic side view of the valve of Fig. 2, associated with a radiator portion in a heat exchange apparatus for working fluids in power machines, according to the first embodiment of the invention, cut-away according to a vertical longitudinal plane passing approximately through the axis of the valve, in an arrangement where the first intercepting assembly is closed, i.e., does not allow the fluid to pass, and the second intercepting assembly is open, i.e., allows the fluid to pass, thanks to the piloting of the valve by the electronic control module;Fig. 5 is a schematic axonometric exploded view of the pilotable valve of Fig. 2;Fig. 6 is a schematic view in vertical cross-section of a radiator in a heat exchange apparatus for working fluids in power machines, according to a further embodiment of the invention, cut-away according to a vertical plane, provided with a three-way bypass valve;Fig. 7 is a schematic side view of the valve associated with a radiator portion according to the further embodiment of the invention of Fig. 6, cut-away according to a vertical plane, in a first operative configuration;Fig. 8 is a schematic side view of the valve of Fig. 7, in a second operative configuration;Fig. 9 is a schematic side view of the valve of Fig. 7, in a third operative configuration;Fig. 10 shows a hydraulic control diagram of the valve of Fig. 7;Fig. 11 is a schematic view in vertical cross-section of a radiator portion in a heat exchange apparatus for working fluids in power machines, according to a variant of the further embodiment of Fig. 6, cut-away according to a vertical plane;Fig. 12 is a schematic side view of a two-way bypass valve, a variant of the two-way valve of Figs. 1-5, associated with a radiator portion in a heat exchange apparatus for working fluids in power machines, according to a further embodiment of the invention, cut-away according to a vertical longitudinal plane passing approximately through the axis of the valve, in a first operative configuration where where the valve is fully closed, i.e. the fluid does not access the fluid discharge path;Fig. 13 is a schematic side view of the valve of Fig. 12 in a second operative configuration, corresponding to the valve fully open due to overpressure;Fig. 14 is a schematic side view of the valve of Fig. 12 in a third operative configuration, corresponding to the valve partially open as a result of the valve being piloted by the electronic control module;Fig. 15 shows a hydraulic / signal functional diagram of an example of a heat exchange apparatus for working fluids in power machines according to the invention, inserted into a hydraulic / signal circuit of a power machine.Detailed description of embodiments

[0096] With reference to the above-mentioned figures, a heat exchange apparatus for working fluids in power machines is indicated as a whole by the reference number 1000, and is shown schematically in Fig. 15.

[0097] For example, the heat exchange apparatus 1000 is provided in a power machine 2000, which includes, for example, a hydraulic circuit 2001, which comprises one or more hydraulic lines (schematized by continuous lines) and is operationally connected with the apparatus 1000.

[0098] The hydraulic circuit 2001 includes, for example, a hydraulic distributor 2010 that distributes power fluid, e.g., oil, to active services, such as hydraulic motors, pumps, hydraulic cylinders, etc., altogether indicated by the reference number 2002. The hydraulic circuit 2001 of the machine 2000 also includes a fluid tank 2004, a pump2005 for moving the fluid, and a motor 2006 of the machine. For example, an inlet line 2008 is provided for the fluid entering the heat exchange apparatus 1000 from the hydraulic circuit 2001, and an outlet line 2009, along which a filter 2011 is arranged, is provided for the fluid, which flows into the tank 2004. The machine 2000 includes an electronic management device 2007, which communicates, through, for example, electrical lines (broken lines), with the various components of the machine, for example the motor 2006 that activates the pump 2005, the hydraulic distributor 2010, and the heat exchange apparatus 1000.

[0099] Preferred embodiments of the radiator provided in the apparatus 1000 are collectively indicated by the reference number 100, while preferred embodiments of the pilotable valve associated with the radiator 100 are collectively indicated by the reference number 10, 200 and 300.

[0100] The heat exchange apparatus 1000 includes a radiator 100, with which a pilotable valve 10 is associated. In this example, the apparatus 1000 also includes a cooling fan 1001, provided with a motor 1002 (which can be and electric or hydraulic motor), for cooling the radiator 100, a first and a second temperature sensors 109 A and 108C, and pressure sensors Pl and P2, whose operation is better described below. The apparatus 1000 also includes an electronic control module 1020, operationally connected with the various components of the apparatus, operationally connected, through one or more internal ports 1021, with the pilotable valve 10, 200, 300 and preferably also with the temperature and pressure sensors and the fan motor.

[0101] Appropriately, the electronic control module 1020 also includes, in this example, an external communication port 1022 configured to communicate with the electronic management device 2007 of the machine 2000. In other examples, the electronic control module 1020 can be completely autonomous and communicate only with the components of the heat exchange apparatus 1000.

[0102] As shown in Figs. 1 and 6, the radiator 100 includes a box-shaped body 101 provided with flanges and bases 102 for fastening to the hydraulic machine with which the radiator is to be associated.

[0103] On two opposite sides of the box-shaped body 101, a first and a second trays 103 and 104 are provided, connected with each other by means of a plurality of heatdissipation channels 105 that are mutually separated by finned surfaces 106 (schematically shown only in some limited portions of the radiator, for the sake of clarity of the drawing) for dissipating the heat that pass through the box-shaped body 101. The first tray 103 is a first manifold that distributes the fluid to the heat dissipation channels 105, and the second tray 104 is a second manifold that collects the fluid from the heat dissipation channels 105.

[0104] A metal perturbation warp 107, indicated by a broken line in only one dissipation channel 105 for the sake of clarity of the drawing, is provided within each dissipation channel 105, for perturbing the motion of the working fluid (e.g., oil) within the channels 105, promoting the transfer of heat to the surfaces of the channels 105.

[0105] The radiator inlet for the fluid is indicated by IN and is provided, for example, in a sleeve 108 A connecting the first tray 103 to a hydraulic circuit (not shown in the figures) from which the working fluid comes. The radiator outlet for the fluid is indicated by US and is provided, for example, in a sleeve 108B connecting the second tray 104 to a discharge line for discharging into the circuit tank, from which a pumping system takes the fluid back into the hydraulic circuit and circulates it again.

[0106] It should be noted that the heat dissipation channels 105 form a heat dissipation path D for the fluid between the radiator inlet IN and the radiator outlet US.

[0107] In this example, the first tray 103 has a second sleeve 109 designed to accommodate, for example, the first temperature sensor 109 A.

[0108] The working fluid enters the first tray 103 under a given pressure and passes into the second tray 104 through the heat dissipation channels 105.

[0109] In this example, the first tray 103 has a length less than the length of the second tray 104, and has, at an end thereof, a flow deviation compartment 110 for deviating the flow from the first tray 103 directly to the second tray 104, by means of one or more deviation channels 111, parallel to the dissipation channels 105 and free of metal perturbation warp. The flow deviation compartment 110 and the deviationchannels 111 form a fluid discharge path S adapted to bypass the heat dissipation path D formed by the heat dissipation channels 105.

[0110] It should be noted that the deviation compartment 110 forms a branch between the inlet IN and the beginning of the heat dissipation path D formed by the heat dissipation channels 105. The fluid discharge path S begins at this branch.[oni] The flow deviation compartment 110 has a first outlet port 112, which connects the deviation compartment 110 with the first tray 103, and one or more delivery ports 113, which connect the deviation compartment 110 with the deviation channels 111.

[0112] The valve 10 is housed in the deviation compartment 110, and is designed to allow the fluid to flow / to prevent the fluid from flowing from the first tank 103 to the compartment 110, according to operational needs explained below.

[0113] With particular reference to Figs. 2 through 5, an embodiment of the bypass valve 10 includes a liner 11, for example in the form of a tubular sleeve, which has a central axis coinciding with the axis X.

[0114] The liner 11 has two portions of different widths, a first portion 12 and a second portion 13.

[0115] The first portion 12 of the liner 11 has a cylindrical shape, and is provided, on its outer surface, with a fastening system, such as a thread 11 A, for connection with a counter-thread provided in a seat of the compartment 110, which takes the form, for example, of a through-hole 114, for accessing the inside of the compartment from the outside of the radiator.

[0116] Therefore, the valve 10 is inserted into the compartment 110 by screwing the first portion 12 into the through-hole 114. In this example, the first portion 12 has an axial length (according to the axis X) greater than the axial length of hole 114, and therefore protrudes within the compartment 110.

[0117] As mentioned, the second portion 13 of the liner 11 has a width greater than the width (i.e., the diameter) of the first portion 12. The second portion 12 issubstantially external to the compartment 110 and has a face 14 abutting against the outer edge 115 of hole 11 A, with the interposition of a gasket 15.

[0118] The valve 10 includes two intercepting assemblies for intercepting the working fluid.

[0119] A first fluid intercepting assembly, indicated as a whole with the reference number 20, comprises a first shutting member 21, slidably arranged within a first chamber 22 defined by the inner space of the first portion 12 of the liner 11.

[0120] More specifically, the inner wall 16 of the first portion 12 of the liner 11, i.e., of the first chamber 22, forms an axial guide along the axis X for the first shutting member 21. In this example, the first shutting member 21 is in the form of a glassshaped body, with a base 23 and an annular wall 24 extending from the base 23 and sliding over the inner wall 16 of the first chamber 22.

[0121] A closing surface 25 of the first shutting member 21 is defined on the base 23 and is adapted to abut in a sealing manner, when closing, against a stop 116 defined on the periphery of the first discharge port 112 of the compartment 110.

[0122] A reversibly compressible device 27 is provided in the first chamber 22, in this example an axial spring, e.g., a helical spring, having a first end, adapted to abut against the bottom of the first chamber 22, and a second end, adapted to abut against the base 23 of the glass-shaped body defining the first shutting member 21.

[0123] When the valve 10 is in place in the radiator, the axial spring 27 is compressed and therefore pushes the first shutting member 21 out of the first chamber 22.

[0124] The spring is designed to compress when a given calibration value is exceeded, for example a given limit pressure of the fluid pushing on the outer surface of the base 23. This pressure value is defined "overpressure" value and is chosen on the basis of the maximum pressure to be allowed for the fluid circulating through the radiator.

[0125] The first intercepting assembly essentially forms an overpressure protection unit H of mechanical type, and the operation thereof is substantially as described below. While closing the first discharge port 112 of the compartment 110, the glass-shaped body defining the first shutting member 21 protrudes with its base 23 out of the first chamber 22, with the base touching the stop 116 defined on the periphery of the first discharge port 112. When the pressure in the first tray 103 increases above the overpressure limit value, the shutting member 21 moves axially, thus compressing the spring 27, as shown in Fig. 3. The fluid thus enters the compartment 110 and flows to the second tray 104 through the deviation channel 111.

[0126] The spring 27 practically prevents the movement of the first shutting member 21 from the shutting position where the closing surface 25 of the first shutting member 21 abuts against the stop 116 on the first discharge port 112 of the compartment 110. When the given "overpressure" of the fluid against the first shutting member 21 is exceeded, the latter is adapted to move from the shutting position to an access position, where the spring 27 is further compressed, and the first discharge port 112 is thus opened, with the fluid F thus flowing through the first intercepting assembly, entering the compartment 110.

[0127] The maximum opening stroke of the first shutting member 21 is limited by the end edge of the first chamber 22, against which the base 23 can abut, with the spring 27 being compressed at the most.

[0128] The valve 10 also includes a second fluid intercepting assembly, indicated as a whole with the reference number 30.

[0129] The second fluid intercepting assembly 30 also includes a second shutting member 31 capable of closing / opening on command the passage of the fluid through a second discharge port B defined by a section 32 of the second intercepting assembly 30.

[0130] Similarly to the first intercepting assembly 20, also in the second intercepting assembly 30 the second shutting member 31 is movable from a closing position, adapted to close the second discharge port B defined by the section 32, to an opening position of the section 32, where the fluid is allowed to flow through the second intercepting assembly toward the discharge path S.

[0131] The first and second intercepting assemblies allow the fluid to pass through different and independent passages, so it is possible for the fluid to pass the valve 10through only the first intercepting assembly 20, or through only the second intercepting assembly 30, or through both.

[0132] Whilst the first intercepting assembly 20 is purely mechanical, and the movement of the first shutting member 21 is allowed by the reversibly compressible device 27 on the basis of a pressure value of the fluid entering the radiator higher than the overpressure value, the second intercepting assembly 30 is pilotable, e.g., electro- mechanically pilotable, and the movement of the second shutting member 31 is allowed by an electrically controlled pilot actuator 50, better described below.

[0133] The second intercepting assembly 30 includes a tubular body 33A projecting from the bottom of the first chamber 22 and defining a fluid access duct 33 toward the passage section 32. The fluid access duct 33 is parallel to the axis X, and more preferably its direction of extension is coincident with the axis X.

[0134] Appropriately, the tubular body 33A with the access duct 33 passes through the closing surface 25 of the first shutting member 21, so that the access duct 33 has a fluid inlet end 34 positioned outside the first chamber 22 and always beyond or at the closing surface 25 (even when positioned, when closing, on the stop 116 in the first discharge port 112 of the compartment 110), i.e., the inlet end 34 of the access duct 33 is external to the compartment 110.

[0135] The bottom of the first chamber 22 is realized by an intermediate body 36 that practically divides the inside of the liner 11 into two parts, the first chamber 22 and a second chamber 37.

[0136] A terminal body 38 is provided in the second chamber 37, which closes the liner 11 and delimits, with the intermediate body 36, a first cavity 39, into which the access duct 33 ends through the intermediate body 36.

[0137] The tubular body 33A with the access duct 33 is fastened at a through-hole provided through the intermediate body 36, and the duct 33 therefore ends into the first cavity 39. It should be noted that, in this example, the tubular body 33 A has, at its end, an enlarged portion 33B that is wider than the hole passing through the base 23 of the first shutting member 21, into which it is inserted, so that the first shutting member,when the bypass valve is not associated with the radiator, abuts against the enlarged portion 33B.

[0138] The terminal body 38 is fastened, for example, screwed, to the inner wall of the liner 11, with the interposition of gaskets 40.

[0139] The intermediate body 36 has an annular flange 36A protruding from the body and abutting against an annular shoulder 1 IB of the liner 11. An elastic element, such as a helical spring 36B, always in compressed arrangement, is provided between the terminal body 38 and the intermediate body 36, keeping the intermediate body abutting against the annular shoulder 11 A.

[0140] A support element 42 for supporting the second shutting member 31 is fastened, for example, screwed, to the terminal body 38, with the interposition of a gasket 41. In particular, in the support element 42, a housing 43 is provided, in which the second shutting member 31 is adapted to slide, preferably in a direction parallel to the axis X, and more preferably in a direction coincident with the axis X.

[0141] A second cavity 44 is delimited between the terminal body 38 and the support element 42, which is fluidly connected with the first cavity 39 through a perforation 45 (shown in the section of Fig. 2).

[0142] The second discharge port B / passage section 32 of the second shutting member 31 is defined on the terminal body 38. The discharge portion / passage section provides for a duct passing through the terminal body 38, formed by a transverse segment 46A and an axial segment 46B, ending into the second cavity 44 at the seat 47 where the head of the second shutting member 31 rests, i.e., corresponding to the closing position of the latter.

[0143] The duct 46A-46B is connected with further discharge segments 49 (shown in Figs. 3 and 4) provided within the body of the liner 11, ending into the compartment 110 in an axial position between the closing surface 25 and the section 32 by means of, for example, channels provided along the surface of the hole 114 of the compartment 110 (these channels are not shown in the figures, but the passage of the fluid F is schematically shown by a broken line in Fig. 4).

[0144] In this example, the second intercepting assembly 30 is essentially a solenoid valve.

[0145] The second shutting member 31 is integral to a piston 51 of the solenoid-type pilot actuator 50. The piston body is guided axially within the housing 43 of the support element 42. Around the support element 42, a solenoid 52 is provided, electrically connected to an external wiring system, not shown in the figures. A ring 53 makes the solenoid 52 integral to the support element 42.

[0146] An elastic element 55 is provided between the bottom of the housing 43 and the base of the piston 51, for example a helical spring, always compressed and adapted to push the piston, i.e., the second shutting member 31, into the closing position. A further duct 56, simply schematized through a broken line, directly connects the space 51 A between the face, on which the spring element 55 of the piston 51 acts, and the bottom of the housing 43 with the second cavity 44.

[0147] The operation of the first intercepting assembly 20 has already been described above. As regards the operation of the second intercepting assembly 30, the following should be noted.

[0148] The access duct 33 directly connects the first cavity 39 and the first tray 103 through the intermediate body 36. In turn, the first cavity is directly connected, through the hole 45, to the second cavity 44, which is in turn directly connected to the space between the piston 51 and the bottom of the housing 43 thereof. This direct connection have no interruptions, and therefore the access duct 33, the first cavity 39, the second cavity 44, and the space 51 A between the piston 51 and the bottom of the housing 43, are at the same pressure as the first tray 103.

[0149] The actuator 50 is usually unenergized, and therefore the second shutting member 31 is usually in the closing position (Figs. 2 and 3), kept by the spring 55 (it should be noted that the spring does not need to be particularly rigid, as it has simply the function of ensuring that it is held in position against, for example, gravity, the piston being generally in pressure equilibrium with the tray 103; the same applies to the spring 36B).

[0150] Once the solenoid of the actuator is energized, the second shutting member 31 is moved to the opening position (Fig. 4), and the fluid contained in the second cavity 44 flows toward the compartment 110 (and therefore toward the second tray 104 through the channels 111) passing through the segments 46A, 46B and 49.

[0151] For example, through the electronic control module 1020, the second intercepting assembly 30 can be operationally connected with the first temperature sensor 109A positioned in the sleeve 109 to enable a "thermostatic" operation of the valve. As long as the temperature in the first tray 103 is below a limit value, the second intercepting assembly 30 is open (actuator energized) and the fluid is deviated also to the channels 111 in the second tray 104. If the fluid temperature exceeds the limit value, i.e., the minimum optimal operating temperature is reached, the second intercepting assembly is closed (actuator not energized).

[0152] The possibility of piloting the valve, for example through an electrical control of the opening / closing of the second intercepting assembly, and the association with a temperature sensor, can be useful for other applications, such as flow rate modulation through the bypass valve. In fact, in the latter case, it is possible, for example, to reduce the fluid flow rate in a given time interval, to control a train of subsequent open-closed pulses in the same time interval, so that the average flow rate is lower than the maximum flow rate achievable by keeping the second intercepting assembly always open.

[0153] It is clear that piloting can be different from what indicated above; it can be a piloting (and corresponding actuator) of mechanical, hydraulic, pneumatic type, in a basically known way, however managed and controlled by an electronic control module that sends the piloting command.

[0154] As mentioned above, it is possible to use valve 10, through the control of the second intercepting assembly, to vary in a predetermined way, at the desired time instant, the quantity of working fluid to be sent to the discharge path S that bypasses the heat dissipation path D. In this way, the fluid pressure in the radiator can be controlled more precisely and the pressure peaks can therefore be handled in an improved way.

[0155] The control of the pilotable valve by the electronic control module 1020 will be described in more detail below.

[0156] As mentioned above, in practice, the compartment 110 forms a branch between the inlet IN and the beginning of the heat dissipation path D formed by the heat dissipation ducts 105, the fluid discharge path S beginning, and the second discharge port B being provided, in that branch. Therefore, the pilotable valve 10 can be seen as a two-way valve associated with the second discharge port B without interrupting the flow of fluid from the inlet IN toward the heat dissipation ducts 105 (i.e., the flow in the first tray 103), so that when piloting the second intercepting assembly 30 of the valve 10 adapted to keep the valve open, the fluid is adapted to pass through the heat dissipation path D and the second discharge port B at the same time, toward the discharge path S including the deviation channel 111, whilst, when piloting the second intercepting assembly 30 of the valve 10 adapted to keep the valve closed, the fluid is adapted to pass through only the heat dissipation path D.

[0157] A variant 300 of the two-way pilotable bypass valve 10 described above is shown in Figs. 12 through 14. The bypass valve 310 includes a liner 311, for example in the form of a tubular sleeve, which has a central axis coinciding with the axis X.

[0158] The liner 311 has two portions of different widths, a first portion 312 and a second portion 313.

[0159] The first portion 312 of the liner 11 has a cylindrical shape, and is provided, on its outer surface, with a fastening system, such as a thread 311A, for connection with a counter-thread provided in a seat of the compartment 110, which takes the form, for example, of a through-hole 114, for accessing the inside of the compartment from the outside of the radiator.

[0160] Therefore, the valve 310 is inserted into the compartment 110 by screwing the first portion 312 into the through-hole 114. In this example, the first portion 312 has an axial length (according to the axis X) greater than the axial length of hole 114, and therefore protrudes within the compartment 110.

[0161] As mentioned, the second portion 313 of the liner 11 has a width greater than the width (i.e., the diameter) of the first portion 312. The second portion 313 issubstantially external to the compartment 110 and has a face 314 abutting against the outer edge 115 of hole 11 A, with the interposition of a gasket 315.

[0162] In this example, differently from the previous example, the valve 310 comprises a single intercepting assembly 320 for intercepting the working fluid, which comprises a single shutting member 321, slidably arranged within a first chamber 322 defined by the inner space of the first portion 312 of the liner 311.

[0163] More specifically, the inner wall 316 of the first portion 312 of the liner 311, i.e., of the first chamber 322, forms an axial guide along the axis X for the first shutting member 321. In this example, the first shutting member 321 is in the form of a glassshaped body, with a base 323 and an annular wall 324 extending from the base 323 and sliding over the inner wall 316 of the first chamber 322.

[0164] A closing surface 325 of the first shutting member 321 is defined on the base 323 and is adapted to abut in a sealing manner, when closing, against a stop 116 defined on the periphery of the first discharge port 112 of the compartment 110.

[0165] A reversibly compressible device 327 is provided in the first chamber 322, in this example an axial spring, e.g., a helical spring, having a first end, adapted to abut against the bottom of the first chamber 322, and a second end, adapted to abut against the base 323 of the glass-shaped body defining the first shutting member 321.

[0166] When valve 310 is in place in the radiator, the axial spring 327 is compressed and therefore pushes the first shutting member 321 out of the first chamber 322.

[0167] The spring is designed to compress when a given calibration value is exceeded, for example a given limit pressure of the fluid pushing on the outer surface of the base 323. This pressure value is defined "overpressure" value and is chosen on the basis of the maximum pressure to be allowed for the fluid circulating through the radiator.

[0168] The intercepting assembly 320 essentially forms an overpressure protection unit 3H of mechanical type, and the operation thereof is basically similar to that of the assembly H described above. While closing the first discharge port 112 of the compartment 110, the glass-shaped body defining the first shutting member 321protrudes with its base 323 out of the first chamber 322, with the base touching the stop 116 defined on the periphery of the first discharge port 112, as shown in Fig. 12.

[0169] When the pressure in the first tray 103 increases above the overpressure limit value, the shutting member 321 moves axially, thus compressing the spring 327, as shown in Fig. 13. The fluid thus enters the compartment 110 and flows to the second tray 104 through the deviation channel 111.

[0170] The spring 327 practically prevents the movement of the first shutting member 321 from the shutting position where the closing surface 325 of the first shutting member 321 abuts against the stop 116 on the first discharge port 112 of the compartment 110. When the given "overpressure" of the fluid against the first shutting member 321 is exceeded, the latter is adapted to move from the shutting position to an access position, where the spring 327 is further compressed, and the first discharge port 112 is thus opened, with the fluid F thus flowing through the first intercepting assembly, entering the compartment 110.

[0171] The maximum opening stroke of the first shutting member 321 is limited by the end edge of the first chamber 322, against which the base 323 can abut, with the spring 327 being compressed at the most.

[0172] The pilotable valve 310 includes a pilot actuator 350, configured to move the first shutting member 321 axially along X between the shutting position (Fig. 12) and a position for accessing the compartment 110 (Fig. 14), against the resistance of the spring 327 and thus allowing the fluid F to pass through the first discharge port 112.

[0173] The bottom of the first chamber 322 divides the inside of the liner 311 into two parts, the first chamber 322 and a second chamber 337.

[0174] The pilot actuator 350 is fastened to the liner 311, for example by means of a support element 342, e.g., screwed to the inner walls of the second chamber 337.

[0175] The support element 342 is internally hollow and defines, together with the liner 311, the second chamber 337. A piston 351 of the pilot actuator 350, which in this example is of the solenoid type, is provided within the second chamber 337. The piston 351 is slidable in the direction of movement of the first shutting member 321.

[0176] Around the support element 342, a solenoid 352 is provided, electrically connected to an external wiring system, not shown in the figures, and operatively connected to the electronic control module CEN. A ring 353 makes the solenoid 352 integral to the support element 342.

[0177] The pilot actuator 350 also includes a stem 333 that projects from the base 323 (e.g., integral to the base by means of a threaded connection) of the shutting member 321 and extends toward the piston 351, passing through a hole 360 provided in the bottom of the first chamber 322.

[0178] The 336 end of the stem 333 is thus arranged within the second chamber 337 and interacts with the piston 351. In practice, as mentioned above, the pilot actuator 350 moves, through the piston 351, the first shutting member 321, acting on the stem 333, which is integral to the shutting member.

[0179] In this example, the end 336 of the stem 333 is provided with a coupling portion 361, e.g., a portion enlarged with respect to the width of the stem, while the piston 351 is provided with a gripping portion 362 adapted to abut against the face 363 of the coupling portion 361 facing the base 323, i.e., in the direction of shutting of the discharge port 112. When, following the energization of the solenoid (Fig. 14), the piston is forced in the direction opposite to the direction of shutting of the discharge port 112, the gripping portion 362 of the piston 351 abuts against the face 363 of the coupling portion 361, moving the stem 333, and thus the base 323, i.e., the first shutting member 321 (against the resistance of the spring 327), away from the first discharge port 112, i.e., to the access position of the first discharge port 112.

[0180] When the piston is free, i.e., the solenoid is not energized, the spring 227 brings the first shutting member 321 again to the shutting position of the first discharge port 112 (Fig. 12).

[0181] When the first discharge port 112 is closed by the first shutting member 321 (and thus the solenoid is not energized) and there is overpressure at the first discharge port, as mentioned above, the first shutting member is moved due to the simple mechanical effect of the fluid thrust on the base 323, against the resistance of the spring 327 (Fig. 13). The push on the base 323 causes the stem 333 to move as well. Stroke space SP is provided on the piston body for the end head 366 of the stem 333 to travel.In practice, the end head 366 of the stem abuts against an abutment 364 formed on the body of the piston 351, adequately spaced from the gripping portion 362, pushing the piston in the direction opposite to the direction of shutting of the first discharge port 112.

[0182] One or more passages 367 are realized on the body of the piston 351 that connect the second chamber with the back of the piston, so as to allow any fluid entering the valve to move.

[0183] Figs. 6 through 9 show a third embodiment of the radiator according to the invention, which includes a different pilotable valve, indicated by the reference number 200.

[0184] In this an example, the pilotable valve 200 is a three-way valve, wherein a first way is associated with the fluid inlet IN in the radiator 100, a second way is associated with the heat dissipation path D comprising the heat dissipation channels 105, and a third way is associated with a second discharge port B toward the fluid discharge path S bypassing the heat dissipation path 105, so that, depending on the piloting of the valve, the fluid from the radiator inlet IN is directed only towards the heat dissipation path D, only through the second discharge port B,- both towards the heat dissipation path D and the second discharge port B.

[0185] For example, the pilotable valve 200 comprises a valve body 211 provided with an inner compartment 222, on which a first opening is defined, associated with the radiator inlet IN (hereafter this first opening will be also indicated with IN), a second opening 208A, associated with the heat dissipation path, and a third opening , associated with the second discharge port B (hereafter the third opening will be also indicated with IN).

[0186] An axial sliding seat is defined in the inner compartment 222 for a shutting member 231 movable in a shutting direction X depending on the valve piloting, wherein, along the shutting direction, the shutting member 231 is adapted to take different positions, as further explained below.

[0187] In the example of Figs. 1-5, the pilotable valve is inserted inside the boxshaped body of the radiator. Differently, in the described example, the valve 10 is integrated into the radiator with the valve body 211 fastened, with a face thereof, to an outer face of the box-shaped body 101 of the radiator in correspondence of the first tray 103 and the compartment 110, so that the second opening 208 A and the third opening B of the valve are arranged at respective passages realized on the wall of the box-shaped body 101 to access, respectively, the first tray (the first manifold) and the compartment 110 to access, through a delivery port H IM, to the deviation channel 111 (inside the box-shaped body 101 of the radiator). It should be noted that, compared with the previous example, the compartment 110 and the first tray 103 are completely separated by a wall HOP.

[0188] The body 211 of the pilotable valve is fastened to the box-shaped body 101 of the radiator, for example, by means of screws 211V and respective gaskets G at the ports.

[0189] Similarly to the previous example, the heat dissipation channels 105, provided with a metal perturbation warp 107, extend from the first tray (first manifold) 103 to the second tray 104 (second manifold). The outlet US of the radiator is realized, for example, along the deviation channel 111.

[0190] For example, a back-flow valve 301 may be also provided, that prevents the fluid from flowing back to the heat dissipation channels in the case of overpressure downstream of the radiator, avoiding overpressure propagating into the radiator. The back-flow valve 301 is arranged, for example, between the second manifold 104 and the radiator outlet US. For example, the back-flow valve 301 is arranged at an end of the second tray, at the ends of the deviation channel 111. Therefore, the fluid F in the second tray passes through the back-flow valve 301 and flows to the outlet US, whilst the fluid F in the deviation channel, coming from the discharge port B of the pilotable valve 200, exits directly to the outlet US, without reaching the second tray.

[0191] Fig. 7 shows an enlargement of the pilotable valve 200 (it should be noted that the cross-sectional view is shown from the opposite side with respect to the case of Fig. 6, so the position of the components is mirrored with respect to Fig. 6).

[0192] The shutting member 231 has a central passage portion 260 and two opposite shutting portions 261 and 262, respectively of a first shutting portion for shutting the second opening 208 and a second shutting portion for the discharge port (third opening ) B, provided at opposite sides of the central passage portion. To allow fluid to pass through, the transverse width of the central passage portion 260 is less than the transverse width of the shutting portions 261-262.

[0193] As shown, the shutting member 231 has two opposite ends. Preferably, a first end is provided on the first shutting portion 261, while the second end is provided on the second shutting portion 262.

[0194] For example, at the first end, a pilot actuator 250, for example a solenoid actuator, is adapted to act in a known manner (arrow K), which allows the axial movement of the shutting member. Therefore, the piloting of the shutting member is electrical (in practice, the pilotable valve 200 is a solenoid valve). It is clear that piloting can be different from what indicated above; it can be a piloting (and corresponding actuator) of mechanical, hydraulic, pneumatic type, in a basically known way.

[0195] The second end of the second portion 262 of the shutting member 231 abuts against a return element 227 for returning the shutting member 231 (essentially a reversibly compressible device, such as a helical spring) in a direction opposite to the direction of actuation imposed by the actuator 250.

[0196] Adequately, the second portion 262 of the shutting member and the return element 227 for an overpressure protection unit H of the mechanical type, arranged downstream of the inlet IN and adapted to divide the flow of the working fluid from the inlet so that the working fluid is adapted to flow at least partially through the discharge port B to be discharged at least partially into the discharge path S when a mechanical calibration threshold, given by the elastic stiffness of the spring 227, is exceeded, as better explained below.

[0197] The operation of the valve 200 is as follows.

[0198] With reference to Figs. 6 and 7, the shutting member 231 is in a position of operation of the radiator according to a substantially normal fluid operating pressure,where the fluid is fully conveyed from the inlet IN to the second opening 208 to access the first manifold / first tray 103 and flow through the heat dissipation path D. In this configuration, the pilot actuator 250 is not energized, i.e., it does not push the shutting member, and the spring 227 pushes the shutting member 231 so that the second opening 208 is maximally open, i.e., it has the maximum opening area, while the second portion 262 of the shutting member completely closed the discharge port B.

[0199] If a pressure peak occurs exceeding the calibration value of the spring 227, the overpressure protection unit intervenes. The high-pressurized fluid pushes the second portion 262 of the shutting member, and the second portion compresses the spring 227, thus opening the discharge port B. This situation is shown in Fig. 8. In the figure, the spring is maximally compressed and the discharge port B is maximally open, i.e., it has the maximum opening area. At the same time, in this situation, the first portion 261 of the shutting member is so positioned as to close completely the second opening 208, so that all fluid flow is directed through the discharge port B toward the fluid discharge path C. The movement of the shutting member is realized by the fluid thrust and not by the actuator 250, which is inactive at this stage.

[0200] However, it is clear that the complete closing of the second opening 208 can also be achieved by closing the first portion 261 of the shutting member also by movement by the actuator 250. For example, if a pressure peak is usually expected when the operating machine, with which the radiator is associated, acts in a given way, when this action occurs, the control unit can command the actuator to move the shutting member so as to close the second opening 208, thus avoiding flow entering the heat dissipation channels 105 and preventing a pressure peak from forming in these channels.

[0201] Of course, a mixed situation is also possible (Fig. 9), where the shutting member 231 is positioned along the direction X so that the first portion 261 and the second portion 262 only partially close the second opening 208 and the third opening / discharge outlet B, respectively, allowing the fluid to flow through both the ports. By varying the position of the shutting member 231 along the shutting direction X in a direction or in the opposite one, the closed / open area of the ports can be increased or decreased. An increase in the open area of one port corresponds to a decrease in the open area of the other port.

[0202] In addition, preferably, the shutting 231 is so configured that by varying (by appropriately acting on the actuator) its position along the shutting direction X, it is possible to keep the second opening 208A fully closed (preventing access to the heat dissipation path) and to increase or to decrease the unclosed area of the discharge port. Similarly, the shutting member 231 is so configured that by varying (by appropriately acting on the actuator) its position along the shutting direction X, it is possible to keep the discharge port completely closed and to increase or to decrease the unclosed area of the second opening .

[0203] Of course, as in the previous examples, the valve 200 is operationally connected with the electronic control module 1020.

[0204] The valve 200 can operate in "thermostatic" mode, wherein the first temperature sensor, operationally connected with the electronic control module 1020, measures the temperature. For example, if the temperature in the first tray 103 is below a limit value, the shutting member is positioned (by the actuator) so as to allow the fluid to flow at least partially through the discharge port B, i.e., deviated toward the channels 111 as well. If the fluid temperature exceeds the limit value, i.e., the minimum optimal operating temperature is reached, the discharge port B can be completely closed.

[0205] It is therefore clear that this valve allows a high degree of flexibility and possibility of programming the management of fluid flow in the radiator. The movement of the shutting member is of the continuous type along X and not discretized, so that a very fine position adjustment can be achieved. It should be noted that a pilotable valve control can be realized according to proportional logic. For example, the pilotable valve has a proportional pilot control N, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal, that can be linked, for example, to temperature, pressure, or flow rate.

[0206] An example of hydraulic and control scheme of the three-way valve 200 is shown in Fig. 10.

[0207] It is therefore possible to modulate the flow of the fluid to the heat dissipation path or to the discharge path in the most appropriate way, realizing optimal control ofthe pressure in the radiator, which benefits the radiator's strength and the possibility of sizing the radiator more precisely, effectively reducing thicknesses.

[0208] In Fig. I l a radiator with a three-way valve is shown, which is a variant of that of the previous example.

[0209] In Fig. 11, the radiator 100’ has no deviation channels inside the box-shaped body 101’ of the radiator. The discharge path is realized by a duct external to the radiator, and therefore the discharge port B' does not face the box-shaped body of the radiator, but the outside. The other components of the radiator are essentially the same as in the previous example and are indicated by the same reference numbers. The operation is equal to that of the previous example, and will be therefore not described.

[0210] In general, with reference to Fig.15, for all the examples described above, the first temperature sensor 109A is arranged upstream of the heat dissipation path and the second temperature sensor 108C is arranged downstream of the dissipation path. Preferably, these sensors are integrated into the body of the radiator 100 (e.g., associated with the first and second trays 103, 104).

[0211] Similarly, the first pressure sensor Pl is arranged upstream of the heat dissipation path, and the second pressure sensor P2 is arranged downstream of the dissipation path. Preferably, these sensors are also integrated into the body of the radiator 100 (e.g., associated with the first and second trays 103, 104).

[0212] Some operating logics of the heat exchange apparatus are illustrated below, managed by the electronic control module 1020, in combination, if needed, with the electronic management device 2007 when connected together.

[0213] For example, according to a logic of "hydraulic protection" and "pressure optimization" in the radiator, the electronic control module can manage fluid pressure peaks that could damage the radiator. For example, the electronic control module may receive a signal on the fluid pressure at the radiator inlet sent by the pressure sensor Pl. If this is too high, the electronic control module commands the pilotable valve to discharge at least part of the fluid through the discharge path S.

[0214] A similar mode may also include the electronic management device 2007 of the machine 2000, with which the heat exchange apparatus 1000 is associated. Forexample, if an operation associated with the hydraulic circuit 2001 of the machine 2000, operated by the electronic management device 2007, is categorized in the electronic management device 2007 as an operation likely to produce a pressure peak in the fluid when it passes to the radiator, the electronic device, before implementing the operation, can send a signal to the electronic control module 1020 of the apparatus 1000 so that the electronic control module communicates with the valve 10-200-300 and discharges at least part of the fluid through the discharge path S.

[0215] Therefore, situations may occur where it is the electronic management device 2007 that manages in "master" mode the electronic control module 1020, which will be in "slave" mode in order to manage the heat exchange apparatus 100.

[0216] Similarly to what described above, the electronic control module 1020 (autonomously or in combination with the electronic management device 2007 of the machine), can handle cold oil conditions. For example, under cold oil conditions, for example at the first start-up, in the hydraulic circuit of the machine high hydraulic leakage conditions occur, given the high viscosity of the oil. These losses occur mainly in the exchanger, which is an element consisting of small ducts. To avoid these losses, if the temperature measured by the first sensor 109A is below a target value, the electronic control module 1020 commands the pilotable valve 10-200-300 to discharge at least part of the fluid through the discharge path S. In the case of a two-way valves (examples of valves 10 and 300), the valve open bypass allows part of the fluid flow to be discharged, while in the case of a three- or more-way valves (examples of valve 200), the open bypass allows the entire fluid flow to be discharged, which therefore does not pass through the heat dissipation path.

[0217] For example, in general, given a maximum working fluid flow rate through the heat dissipation path for the radiator, the electronic control module 1020 allows to vary the flow rate between the maximum flow rate and a flow rate less than the maximum flow rate for a given interval of time by piloting the pilotable valve 10-200- 300 so that the pilotable valve discharges at least part of the fluid through the fluid discharge path S.

[0218] This change in flow allows to vary the flow passing through the dissipation path, thus influencing the heat exchanged by the radiator, i.e., changing the inlet and outlet temperatures of the fluid.

[0219] The management logics of the electronic control module 1020 (or the electronic management device 2007 of the associated machine) also allow for optimization of the radiator's thermal power, i.e., the heat exchanged. Given a predetermined required thermal power level for the radiator, which is substantially a function of the temperature difference T1-T2 and the pressure difference measured between the first and the second temperature sensors 109A,108C and pressure sensors Pl, P2, the electronic control module 1020 receives the measured temperature and pressure values and calculates the current thermal power level of the radiator (e.g., the power is Pot= m fluid x cp x (T1-T2), where m the mass flow rate of the fluid, and cp the specific heat of the fluid, where m=f(Pl-P2) that is a function (specific to the type of fluid) of the measured pressure difference.

[0220] If the calculated thermal power level is different from the predetermined required thermal power level for the radiator, the electronic control module is so configured as to vary the temperature and / or pressure difference of the fluid through the dissipation path by acting on the pilotable valve 10-200-300 (as mentioned above, by varying the fluid flow rate through the heat dissipation path, the temperature conditions of the fluid at the inlet and outlet change). Along with piloting the valve 10-200-300, it is also possible to act on the speed of the cooling fan 1001 of the radiator, thus better controlling the fluid temperature difference between radiator inlet and outlet.

[0221] For example, if the master electronic management device 2007 of the machine 2000 communicates a new power level Pot to the electronic control module 1020 of the apparatus 1000, the latter can act on the rotational speed of the motor 1002 of the fan 1001, increasing or decreasing it, and at the same time, if necessary, open the discharge path S (the bypass) by acting on the pilotable valve 10-200-300, and therefore part of the fluid (the discharged one) will not be cooled, in order to reach the required thermal power. This is achieved with the new values of T1 and T2 and the flow rate in that time period.

[0222] In general, through a similar logic, it is possible to optimize the output of the radiator through temperature optimization. For example, if the electronic control module 1002 (or the electronic management device 2007) shall have a certain inlet or outlet temperature T1 or T2, the electronic control module 1020 detects the temperature values T1 and T2 from the sensors 109 A and 108C, and, together with the measured pressure values Pl and P2, is able to estimate the flow rate flowing through the exchanger. At this point, the electronic control module 1002 is able to change the temperatures by modulating the speed of rotation of the fan motor (air flow rate that cools the radiator more or less), or (or simultaneously) by opening the pilotable bypass valve 10-200-300 toward the discharge path S.

[0223] The electronic control module 1020 can also command the radiator for a "cleaning" action. For example, it may happen that the thermal performance of the heat exchange apparatus drops during the use thereof. In particular, the finned cooling areas, which are crossed by the air pushed by the fan, can become clogged with dust, stones, and solids of various kinds, thus avoiding the passage of cold air. This condition is intercepted by monitoring the temperature T2 of the fluid exiting the radiator. In fact, if this is higher, under the same conditions of inlet temperature Tl, oil flow rate, and fan rotation speed, the heat transfer is lower, and the oil exits the radiator at higher temperatures.

[0224] In this case, the electronic control module 1020 (or the electronic management device 2007 of the machine 2000 associated therewith), by acting on the motor 1002, can impose the maximum rotation speed on the fan 1001, and then, by taking the inlet and outlet temperature values tl and t2, and the inlet and outlet pressure values pl and p2, estimates the oil flow rate passing through the radiator and calculates the dissipated power. If the power value is lower than expected i.e., the outlet temperature t2 is higher than the expected value (condition of maximum heat transfer), the cleaning cycle is started, which consists of reversing the rotation of the fan 1001, 1001 allowing cleaning of the finned cooling areas, removing dust, stones, solids of various kinds, and opening the pilotable valve toward the discharge path S to discharge at least part of the fluid.

[0225] It is understood that what is illustrated purely represents possible non-limiting embodiments of the invention, which may vary in forms and arrangements withoutdeparting from the scope of the concept on which the invention is based. Any reference numerals in the appended claims are provided for the sole purpose of facilitating the reading thereof in the light of the description above and the accompanying drawings and do not in any way limit the scope of protection.

Claims

Claims1. A heat exchange apparatus for working fluids in power machines, including a portion of hydraulic circuit within which the working fluid is adapted to flow, in said hydraulic circuit portion the following being provided: a radiator, including o a radiator inlet, for the working fluid to enter the radiator, o an outlet, for the working fluid to exit the radiator, o a heat dissipation path for said fluid between said inlet and said outlet, a fluid discharge path adapted to bypass the heat dissipation path, a pilotable valve, arranged upstream of said dissipation path and said discharge path, adapted to manage the flow of the working fluid between the fluid discharge path and the heat dissipation path, an electronic control module, operationally connected to the pilotable valve and configured to pilot the pilotable valve so that the working fluid, depending on the piloting imposed by the electronic control module, is adapted to pass through■ only the heat dissipation path, or■ the fluid discharge path, at least partially.

2. The apparatus of claim 1, including one or more of the following components: a motorized cooling fan for the radiator, operationally connected with the electronic control module, at least one temperature sensor, operationally connected with the electronic control module; preferably at least one first temperature sensor arranged upstream of the heat dissipation path and preferably at least one second temperature sensor arranged downstream of the heat dissipation path; at least one pressure sensor, operationally connected with the electronic control module, preferably at least one first pressure sensor arranged upstream of the heat dissipation path and preferably at least one second pressure sensor arranged downstream of the dissipation path;and wherein the electronic control module is configured to communicate with the above components.

3. The apparatus of claim 1 or 2, wherein, given a maximum working fluid flow rate through the heat dissipation path for the radiator, the electronic control module varies the flow rate between the maximum flow rate and a flow rate less than the maximum flow rate for a given interval of time by piloting the pilotable valve so that the pilotable valve discharges at least part of the fluid through the fluid discharge path.

4. The apparatus of one or more of the preceding claims, wherein the electronic control module provides for one or more of the following operation modes:- the electronic control module receives a signal about a possible peak pressure in the fluid entering the heat dissipation path, thus the electronic control module commands the pilotable valve to discharge at least part of the fluid through the fluid discharge path;- the electronic control module receives a signal about low temperature of the fluid entering the heat dissipation path, thus the electronic control module commands the pilotable valve to discharge at least part of the fluid through the fluid discharge path.

5. The apparatus of one or more of the preceding claims, wherein the electronic control module includes at least one communication port configured to be connected with an electronic unit, external to the heat exchange apparatus and belonging to the power machine with which the heat exchange apparatus is associated, said electronic control module being configured to receive signals from outside the apparatus and to process the signals to enable at least part of the operation of the apparatus.

6. The apparatus of claim 2, wherein a predetermined required thermal power level for the radiator is provided, which is substantially a function of the temperature difference and pressure difference between the first and the second temperature and pressure sensors, wherein the electronic control module calculates the temperature and pressure difference values and calculates the radiator thermal power level and, if the calculated thermal power level is different from thepredetermined required thermal power level for the radiator, the electronic control module is so configured as a. to vary the temperature and / or pressure difference by varying the fluid flow rate through the heat dissipation path by acting on the pilotable valve, or b . to vary the temperature difference by acting on the speed of the radiator cooling fan, or c. appropriately to implement both solutions a and b.

7. The apparatus of one or more of the preceding claims, wherein a first predetermined fluid temperature is provided upstream of the heat dissipation path and / or a second predetermined fluid temperature is provided downstream of the heat dissipation path, wherein the electronic control module calculates the first and / or second temperature values by means of the first and second temperature sensors, and, if the first and / or second temperature values differ from the first and / or second predetermined fluid temperature, the electronic control module is so configured as- to vary the first and / or second temperature values by varying the fluid flow rate through the heat dissipation path by acting on the pilotable valve, or- to vary the first and / or second temperature values by acting on the speed of the radiator cooling fan, or appropriately to implement both solutions a and b.

8. The apparatus of one or more of the previous claims, wherein the pilotable valve is a two-way valve of the open / closed type adapted to close at least one first discharge port to the fluid discharge path, and wherein the change in the flow rate through the heat dissipation path occurs by keeping the valve always open in the given time interval by the electronic control module, or by a train of subsequent open-closed pulses in the same time interval sent to the valve by the electronic control module, whereby the fraction of flow rate through the valve has a lower average value than the maximum flow rate achievable by keeping the valve always open; ora valve with at least three ways, wherein a first way is associated with the fluid entering the radiator, a second way is associated with a discharge port toward the heat dissipation path, and a third way is associated with the discharge port, so that, depending on the piloting of the valve, the fluid is directed only towards the heat dissipation path, only through the discharge port,- both towards the heat dissipation path and the discharge port; whereby the change in the flow rate through the heat dissipation path occurs by keeping the fluid directed toward both the heat dissipation path and the discharge port in the given time interval; preferably, the pilotable valve has a proportional pilot control, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal.

9. The apparatus of any one or more of the preceding claims, wherein the radiator includes at least one portion of the fluid discharge path adapted to bypass the heat dissipation path, wherein the portion of the discharge path includes at least one first discharge port, adapted to provide access to the discharge path, and wherein the pilotable valve is adapted to divide the flow of the working fluid, coming from the radiator inlet, between the at least one discharge port toward the discharge path and the heat dissipation path, so that the working fluid, depending on the piloting of the valve, is adapted to pass through- only the heat dissipation path, or- the at least one discharge port, so that the fluid is discharged at least partially into the discharge path.

10. The apparatus of one or more of the preceding claims, wherein the radiator includes a first manifold, into which the fluid from the inlet enters, a plurality of heat dissipation channels, directly connected with the first manifold, through which the fluid from the first manifold flows, a second manifold, operatively connected with the plurality of heat dissipation channels, into which the fluid from the plurality of heat dissipation channels arrives;the radiator preferably including at least one deviation channel adapted to connect the first manifold and the second manifold, wherein the deviation channel is distinct from the heat dissipation channels.

11. The apparatus of one or more of the preceding claims, including an overpressure protection unit of the mechanical type, arranged downstream of the radiator inlet and adapted to divide the flow of the working fluid from the inlet so that the working fluid is adapted to flow at least partially through the at least one first discharge port to be discharged at least partially into the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceeded.

12. The apparatus of one or more of the preceding claims, wherein between the radiator inlet and the heat dissipation path a branch is provided, in which there is said at least one portion of the fluid discharge path provided with a first discharge port, and wherein the pilotable valve is a two-way valve associated with the first discharge port without interrupting the flow of the fluid from the inlet to the heat dissipation path, so that, if the valve is piloted so as to be kept open, the fluid is adapted to pass simultaneously through- both the heat dissipation path and the first discharge port toward the discharge path, while if the valve is piloted so as to be kept closed, the fluid is adapted to pass through only the heat dissipation path.

13. The apparatus of one or more of the previous claims, wherein the pilotable valve includes an overpressure protection unit of the mechanical type, comprising an intercepting assembly for intercepting the fluid passing through a first discharge port towards the fluid discharge path, the intercepting assembly comprising o a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the first discharge port, and at least one access position, adapted to allow the fluid to pass through the first discharge port, ando an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the discharge port, a pilot actuator, adapted to move the first shutting member between the shutting position and the access position against the resistance of the reversibly compressible device, allowing the fluid to pass through the first discharge port.

14. The apparatus of one or more of the preceding claims, wherein the first discharge port ends into a deviation channel inside the radiator body, for bypassing the heat dissipation channels, which connects the manifolds, so that the at least one discharge port is adapted to allow the fluid to pass between the two radiator manifolds.

15. The apparatus of one or more of claims 1 to 12, wherein the pilotable valve includes at least an overpressure protection unit of the mechanical type, comprising a first intercepting assembly for intercepting the fluid passing through a first discharge port towards the fluid discharge path, the first intercepting assembly comprising o a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the first discharge port, and at least one access position, adapted to allow the fluid to pass through the first discharge port, and o an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the first discharge port, a second intercepting assembly for intercepting the fluid passing through a second discharge port toward the fluid discharge path, includingo a second shutting member movable from a closed position, adapted to close the passage of the fluid through the second discharge port, to an open position, adapted to allow the passage of the fluid through the second discharge port, and o a pilot actuator, adapted to move the second shutting member between the closed position and the open position, allowing the fluid to pass through the second intercepting assembly.

16. The apparatus of claim 15, wherein the second valve shutting member is adapted to reversibly close a section defining the second discharge port, internal to the valve, where the fluid passes through the second intercepting assembly, so that the closed position relates to the closing of the fluid passage section and the open position relates to the consent for the passage of the fluid through the fluid passage section; the passage section is preferably provided in a cavity operatively connected with the outside of the valve in correspondence of the first manifold from which the flow of fluid to be blocked / allowed by the valve comes, wherein the second shutting member is movable according to an axial direction and includes a closing head, for closing the passage seat, and a face opposite the head, transverse to the axis of movement of the second shutting member, wherein the face is subject to the same pressure as the fluid in the cavity; preferably the second fluid intercepting assembly comprising a fluid access duct to the passage section, wherein the fluid access duct passes through the closing surface of the first shutting member; the second fluid intercepting assembly preferably including one or more discharge segments fluidly connected with the passage section and ending into a lateral portion of the valve body comprised between the closing surface and the passage section.

17. The apparatus of one or more of claims 13 to 16, wherein the valve comprises a liner defining an inner space, wherein the first shutting member is at least partially contained within the inner space of the liner.

18. The apparatus of one or more of the preceding claims, wherein the valve comprises a liner defining an inner space, wherein the liner has a fastening system for fastening to a seat in the radiator body, with which the valve shall be associated; the fastening system preferably includes a thread provided on the cylindrical outer surface of the liner.

19. The apparatus of one or more of claims 13 to 18, wherein the valve comprises a central axis, and the first shutting member is movable along the central axis; the first shutting member comprising a closing surface adapted to abut, when closing, against a stop.

20. The apparatus of claim 13 and 19, wherein the pilot actuator includes a piston, configured to be controlled so as to move parallel to the central axis, adapted to act on the first shutting member; the first shutting member preferably comprising a base on which the closing surface is defined, a stem extending from the base, the stem having an interaction end for interacting with a gripping portion of the piston.

21. The apparatus of one or more of claims 13 to 20, wherein- the liner has a first chamber open towards the shutting position of the first shutting member, the first shutting member is adapted to slide axially within the first chamber, with the closing surface remaining external to the first chamber,- the reversibly compressible device is of type axially compressible between two ends, wherein a first end is adapted to abut against the bottom of the first chamber, and a second end is adapted to abut against the first shutting member.

22. The apparatus of one or more of the preceding claims, wherein the radiator comprises a box-shaped body provided with a first tray and a second tray, which define the first manifold and the second manifold and which are connected to each other by means of a plurality of heat dissipation channels, mutually separated by finned surfaces; a metal disturbance warp is provided within each dissipation channel; the first tray includes, preferably at an end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has a first discharge port, which connects the compartment with the first tray, and at least one delivery port, which connects the deviation compartment with the at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly.

23. The apparatus of one or more of claims 1 to 12, wherein the pilotable valve is a valve with at least three ways, wherein a first way is associated with theradiator inlet for the working fluid to enter the radiator, a second way is associated with the heat dissipation path, and a third way is associated with the discharge port, so that, depending on the piloting of the valve, the fluid from the radiator inlet is directed only towards the heat dissipation path, only through the discharge port,- both towards the heat dissipation path and the discharge port.

24. The apparatus of claim 23, wherein the pilotable valve comprises a valve body provided with an inner compartment, on which are defined a first opening associated with the radiator inlet, a second opening associated with the heat dissipation path, and a third opening associated with the discharge port, at least one shutting member that is movable in a shutting direction depending on the piloting of the valve, wherein, along the shutting direction, the shutting member is adapted to take positions o of complete shutting of the second opening , with the third opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the second opening completely closed and to increase or to decrease the unclosed area of the third opening , o of complete shutting of the third opening , with the second opening not closed, wherein preferably, by varying the position of the shutting member along the shutting direction, it is possible to keep the third opening completely closed and to increase or to decrease the unclosed area of the second opening .

25. The apparatus of claim 24, wherein the shutting direction is an axial direction and the shutting member has two opposite ends, a first piloting end, on which a pilot actuator acts for axially moving the shutting member in a first direction, and an opposite second end; preferably a return member, for returning the shutting member in a direction opposite to the first direction, abuts against the second end.

26. The apparatus of claim 25, comprising an overpressure protection unit of a mechanical type arranged downstream of the inlet and adapted to divide theflow of the working fluid coming from the inlet so that the working fluid is adapted to flow at least partially through the discharge port to be discharged at least partially towards the discharge path when a mechanical calibration threshold of the overpressure protection unit is exceed, the overpressure protection unit being formed by the part of the at least one shutting member adapted to close the discharge port and a reversibly compressible overpressure device, adapted to prevent the movement of the part of the at least one shutting member from the shutting position; when a given pressure of fluid against the part of the at least one shutting member is exceeded, the part is adapted to move from the shutting position to a position adapted to allow the fluid to pass through the discharge port, compressing the reversibly compressible device; the reversibly compressible device is preferably an elastic spring with predetermined elastic stiffness defining the mechanical calibration threshold.

27. The apparatus of one or more of the preceding claims, wherein the valve comprises a pilot actuator adapted to act on the shutting member to enable the movement thereof along the shutting direction; the actuator being preferably a mechanical, electrical, pneumatic, or hydraulic actuator, or a combination thereof.

28. The apparatus of one or more of the preceding claims, comprising a box-shaped body provided with a first tray and a second tray, which define the first manifold and the second manifold and which are connected to each other by means of a plurality of heat dissipation channels, preferably mutually separated by finned surfaces; a metal perturbation warp is preferably provided within each dissipation channel.

29. The apparatus of claim 28, wherein the first tray includes, preferably at one end thereof, a flow deviation compartment for deviating the flow from the first tray directly to the second tray, by means of the at least one deviation channel free of metal perturbation warp; the deviation compartment preferably has the discharge port, which connects the compartment with the first tray, and at least one delivery port, which connects the deviation compartment with the at least one deviation channel; the first shutting member is preferably adapted to close the first discharge port reversibly; the at least one deviation channel is preferably internal to the box-shaped body of the radiator.

30. The apparatus of one or more of claims 23 to 29, wherein the at least one deviation channel is internal to the box-shaped body of the radiator, and wherein in the box-shaped body of the radiator a discharge compartment is provided, adjacent to the first tray and separate from it, from which the deviation channel starts, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray and the discharge compartment, so that the second opening of the valve and the third opening of the valve are arranged at respective passages provided in the wall of the box-shaped body of the radiator for access to the tray and to the discharge compartment respectively.

31. The apparatus of one or more of the preceding claims, wherein the at least one deviation channel is internal to the box-shaped body of the radiator and the radiator outlet is provided along the at least one deviation channel.

32. The apparatus of one or more of claims 23 to 31, wherein the at least one deviation channel is formed by a pipe external to the radiator, i.e. external to the box-shaped body of the radiator, and wherein the pilotable valve body is fastened, at a face thereof, to an outer face of the radiator in correspondence of the first tray, so that the second opening is arranged in correspondence of a respective passage for accessing the first tray, while the third opening is provided on a face not facing the box-shaped body of the radiator, in order to be connected to the external pipe.

33. The apparatus of one or more of claims 23 to 32, wherein the pilotable valve has a proportional pilot control, so that the degree of opening or closing of the ports of the second and third ways is proportional to the intensity of the valve pilot signal.

34. The apparatus of one or more of the preceding claims, wherein a back-flow valve is provided between the second manifold and the radiator outlet.

35. A pilotable valve of the type configured to be inserted in the heat exchange apparatus of one or more of the preceding claims, wherein the pilotable valve comprisesan overpressure protection unit of the mechanical type, comprising an intercepting assembly for intercepting the fluid passing through a discharge port towards the fluid discharge path, the intercepting assembly comprising o a first shutting member, movable between a shutting position adapted to close the passage of the fluid flowing through the discharge port, and at least one access position, adapted to allow the fluid to pass through the discharge port, and o an overpressure device, reversibly compressible, adapted to prevent the movement of the first shutting member from the shutting position; when a given pressure of the fluid against the first shutting member is exceeded, the shutting member is adapted to move from the shutting position to the access position by compressing the reversibly compressible device and allowing the fluid to pass through the discharge port, - a pilot actuator, adapted to move the first shutting member between the shutting position and the access position against the resistance of the reversibly compressible device, allowing the fluid to pass through the discharge port.

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