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EP-4738044-A1 - DIFFERENTIAL PRESSURE CONTROL VALVE

EP4738044A1EP 4738044 A1EP4738044 A1EP 4738044A1EP-4738044-A1

Abstract

A differential pressure control valve (100) for a hydraulic system (200) is described. The valve (100) comprises an inlet (1i), an outlet (1u), a main channel (2) that connects the inlet (1i) to the outlet (1u), and an auxiliary chamber (4); the valve (100) also comprises a sealing element (3) that separates the main channel (2) from the auxiliary chamber (4) and a control inlet (5) in fluid communication with the auxiliary chamber (4). The valve (100) further comprises a flow control member (7) having an active portion (8) operating in the main channel (2) and cooperating with an intermediate portion (2m) of said main channel, so as to define at least one passage opening (9) of variable width. One of the active portion (8) of the regulating member and the intermediate portion (2m) of the main channel defines a secondary channel (10) that connects the inlet (1i) and the outlet (1u) in fluid communication. A hydraulic system (200) that uses the valve (100) in a return branch of the system is also described. Finally, a method for controlling the hydraulic system (200) is described.

Inventors

  • CIMBERIO, ROBERTO
  • Guidetti, Tiziano
  • CHIARELLO, ANDREA

Assignees

  • CIMBERIO HOLDING S.r.l.

Dates

Publication Date
20260506
Application Date
20250930

Claims (15)

  1. Differential pressure control valve for a hydraulic system, wherein the valve includes: - a valve body (1) defining an inlet (1i), an outlet (1u), a main channel (2) that places the inlet (1i) in fluid communication with the outlet (1u), and an auxiliary chamber (4), - a sealing element (3) separating the main channel (2) from the auxiliary chamber (4), - a control inlet (5) in fluid communication with the auxiliary chamber (4), - a flow regulating organ (7) having an active portion (8) operating in the main channel (2), wherein the valve is configurable in an operating condition wherein the active portion (8) of the flow regulating organ (7) cooperates with an intermediate portion (2m) of said main channel (2), so as to define at least one passage opening (9) of variable amplitude that allows fluid communication between the inlet (1i) and the outlet (1u); characterized by the fact that at least one between the active portion (8) of the flow regulating organ (7) and the intermediate portion (2m) of the main channel (2) defines a secondary channel (10; 10') that places the inlet (1i) and outlet (1u) in fluid communication.
  2. Valve according to claim 1, wherein the secondary channel (10; 10') is configured to constantly place in fluid communication the inlet (1i) and the outlet (1u), regardless of the position of the active portion (8) of the flow regulating organ (7) with respect to the main channel (2).
  3. Valve according to any one of the preceding claims, wherein in said operating condition the active portion (8) of the flow regulating organ (7) is able to reach an end-stroke position wherein the active portion (8) itself acts in abutment against a corresponding counter-surface (11) of the intermediate portion (2m) of said main channel (2), and wherein the secondary channel (10; 10') places the inlet (1i) and outlet (1u) in fluid communication even when the active portion (8) of the flow regulating organ (7) is in said end-stroke position.
  4. Valve according to the previous claim, wherein the active portion (8) of the flow regulating organ (7) includes, on one side facing the counter-surface (11) of the intermediate portion (2m) of the main channel (2): - a continuous base (12), optionally having a flat surface, and - a side wall (13), emerging transversely from the continuous base (12) approaching said counter-surface (11) and defining a cavity of the active portion (8) facing the same counter-surface; optionally wherein the side wall (13) emerges from a perimeter edge of the continuous base (12) and has constant height (h) for a preponderant part of its development around the continuous base, said height (h) being measured perpendicular to the continuous base (12).
  5. Valve according to the previous claim, wherein: - the secondary channel (10) is a through orifice traversing said side wall (13) or said continuous base (12); optionally wherein said through orifice has a curvilinear profile, e.g., circular; or - the secondary channel (10) is defined by a recess present on a free end edge of the side wall (13) opposite the continuous base (12); optionally wherein said recess has a curvilinear profile, e.g., semicircular.
  6. Valve according to the previous claim, wherein the secondary channel (10) is defined by said recess and wherein the free end edge of said side wall (13) lies on the same plane with the exclusion of said recess forming the secondary channel (10), said recess extending transversely to the side wall (13) and traversing the entire thickness of the side wall itself so as to constantly place in fluid communication an internal volume of the cavity defined in the active portion (8) with the outlet (1u) of said main channel (2).
  7. Valve according to any one of the preceding claims, wherein the secondary channel (10; 10') has a net fluid passage section whose area is: - at least 10 times smaller, optionally at least 100 times smaller, than the area of the fluid passage section of said inlet (1i) of the main channel (2); and - at least 10 times smaller, optionally at least 100 times smaller, than the area of the fluid passage section of said outlet (1u) of the main channel (2); and wherein the secondary channel (10; 10') has a net fluid passage cross-section whose area is less than 2 mm 2 , optionally less than 1 mm 2 , for example, between 0.20 and 0.75 mm 2 , optionally where the axial extension of the secondary channel (10; 10') is less than 3 mm, more optionally less than 2 mm, e.g., between 0.15 mm and 1.5 mm.
  8. Valve according to any one of the preceding claims, in combination with claim 3 or 4, wherein the intermediate portion (2m) of the main channel (2) defines an intermediate opening (2a), interposed between the inlet (1i) and outlet (1u), of predetermined size and shape, said intermediate opening being bounded by a radially inner edge (16) of the counter-surface (11); and wherein said radially inner edge (16) emerges transversely with respect to a surrounding flat region (17) of the counter-surface (11), said radially inner edge (16) extending along an entire perimeter of the intermediate opening (2a), coaxially and in a radially inner position with respect to said side wall (13).
  9. Valve according to the preceding claim wherein the secondary channel or an additional secondary channel (10; 10') is defined at and across said radially inner edge (16) of the counter-surface (11).
  10. Valve according to any one of the preceding claims, wherein the secondary channel (10; 10') is distinct from and additional to the main channel (2) and wherein the flow passage cross section of the secondary channel does not change irrespective of the position of the active portion (8) of the flow regulating organ (7).
  11. A valve according to any one of the preceding claims, wherein the sealing element (3) is radially interposed between the flow regulating organ (7) and the valve body (1), and wherein the flow regulating organ (7) is coupled to the sealing element (3) so as to present the active portion (8) operating in the main channel (2); wherein the flow regulating organ (7) comprises a slider body (18) operatively connected to the active portion (8); and wherein said slider body (18), in the operating condition of the valve, is axially movable with respect to the valve body (1) along a predetermined axis (X) to position the active portion (8) of the flow regulating organ (7) in a plurality of positions relative to the valve body (1) resulting in a variable amplitude of the passage opening (9) of fluid, said amplitude being variable according to a value assumed by a pressure differential between a pressure (P+) present in the auxiliary chamber (4) and a pressure (P-) present in the main channel (2).
  12. Valve according to the previous claim, wherein the sealing element (3) comprises a diaphragm of annular conformation having an outer perimeter (3a) fluid-tightly attached to the valve body (1) and an inner perimeter (3b) fluid-tightly attached to an intermediate area of the slider body (18), so that the slider body itself has a portion extending within the main channel (2) and a portion extending within the auxiliary chamber (4); and wherein the flow regulating organ (7) includes a elastic body (19), optionally a coil spring, active on the slider body; and wherein said elastic body (19) is configured to counteract a movement of the slider body (18) and the active portion (8) that reduces the amplitude of the passage opening (9).
  13. A valve according to any one of the preceding two claims, wherein the slider body (18) has tubular conformation and terminally carries the active portion (8), and wherein the flow regulating organ (7) comprises a rod (20), having a portion, optionally a preponderant portion, developing internally to the slider body (18); wherein said elastic body (19) is interposed between said rod (20) and said slider body (18); wherein said rod (20) has a first end portion to which a first end of the elastic body (19) is constrained, and a second end portion passing through an axial opening provided on the slider body (18) on the opposite side of said active portion (8); and wherein, a second end of the elastic body (19) is axially active on the slider body (18).
  14. Valve according to the previous claim, wherein the rod (20) presents: - a first half-part (22) housed internally in the slider body (18), and - a second half-part (23) partially emerging from the slider body (18) and passing through a wall of the valve body (1), wherein the second half-part (23) of the rod has a first end, inside the valve body (1), removably coupled to the first half-part (22), optionally by a threaded coupling, so that the overall length of the rod (20) can be adjusted, and wherein an operating element (24), operable from outside the valve body (1), is coupled to a second end of the second half-part (23) of the rod (20), wherein a rotation of the operating element (24) results in a concordant rotation of the second half-part (23) of the rod (20) and thus an elongation or shortening of the rod (20); optionally wherein the first half-part (22) of the rod (20) is axially movable relative to the slider body (18) at least between the following relative positions: - an extended position, wherein the part of the rod (20) inside the slider body (18) has maximum axial extension, - a contracted position, wherein the part of the rod (20) inside the slider body has minimal axial extension, - a plurality of intermediate positions between the extended and contracted positions.
  15. A hydraulic system (200), optionally of a heating and/or cooling plant, comprising a delivery pipe (202) supplying a predetermined number of users (201), optionally a predetermined number of heat exchangers, and a return pipe (203) configured to receive fluid output from the users, the hydraulic system (200) also comprising a valve (100) according to any one of the preceding claims, wherein the valve (100) is installed on the return pipe (203) with the control inlet (5) connected to the delivery pipe (202) so as to receive a pressure signal from the delivery pipe.

Description

Field of the invention The invention relates to the field of fluid valves and, more specifically, to a differential pressure control valve. The valve may be used for controlling pressure in hydraulic systems for example of heating and/or cooling plants. Background art Differential pressure control valves (DPCVs) are valves equipped with a main conduit having an inlet and an outlet; DPCVs also comprise a diaphragm and a slider body that is movable relative to the valve body itself, which defines an opening of variable width for the passage of a fluid between the inlet and the outlet; the valve slider body is fixed to the diaphragm, which is typically positioned in a chamber divided into a first portion in fluid communication with the main conduit, and a second portion hydraulically isolated from the first portion, which is in fluid communication with an auxiliary control inlet connectable to a desired control point upstream of the user or system in which the valve is installed. Differential pressure control valves are so named because they allow the pressure difference between the first and second portions of the chamber to be kept under control, for example, substantially constant, regardless of the flow of fluid through the main conduit. It should also be noted that DPCV valves of the known type also allow the desired differential pressure value to be set. For this purpose, differential pressure control valves typically have a control that allows the setting of the pressure differential Dp that is desired to be maintained between the first and second portions of the chamber; this control typically includes an adjustment device, for example a screw, which acts on a preload spring acting on the slider body. The differential pressure Dp is set between a minimum and maximum value by operating the adjustment device. The differential pressure control valves described above can be installed, for example, in closed circuits of domestic, industrial, or commercial systems to allow the balancing of the direct flow, in particular but not limited to, cooling or heating systems. Differential pressure control valves are inserted into the system in such a way that the control inlet is connected, via a small pipe, to an inlet or supply pipe of the system, at a control point located upstream of one or more user units (e.g., comprising one or more heat exchangers or other components), while the main pipe of the valve has its inlet and outlet connected in series to the return pipe of the system itself. The applicant noted that, under the operating conditions described, differential pressure control valves are often characterized by unwanted vibrations or rapid and uncontrolled oscillations of the moving parts, in particular the slider body. In certain situations, these vibrations result in multiple contacts between the end of the slider body and the valve body, causing considerable noise and potentially leading to damage. The behavior described may also cause the valve to be substantially unable to ensure compliance with the differential pressure setting value set by the user. Object of the invention In light of the above, one purpose of the invention is therefore to provide a differential pressure control valve that resolves one or more of the above-described drawbacks. More specifically, one purpose of the present invention is to provide a differential pressure control valve in which uncontrolled vibrations of the moving parts during the operational use of the valve are reduced or eliminated. A further purpose is to provide a differential pressure control valve in which mechanical interference is reduced, and noise is therefore minimized. Last but not least, an auxiliary purpose of the invention is to provide a differential pressure control valve that ensures reasonable compliance with the differential pressure setting value set by the user. Summary of the invention Aspects of the invention are described below. A 1st aspect concerns a differential pressure control valve (100) for a hydraulic system; the valve (100) comprises: a valve body (1) defining an inlet (1i), an outlet (1u), a main channel (2) that places the inlet (1i) in fluid communication with the outlet (1u), and an auxiliary chamber (4),a sealing element (3) separating the main channel (2) from the auxiliary chamber (4),a control inlet (5) in fluid communication with the auxiliary chamber (4),a flow regulating organ (7) having an active portion (8) operating in the main channel (2), wherein the valve is configurable in an operating condition wherein the active portion (8) of the flow regulating organ (7) cooperates with an intermediate portion (2m) of said main channel (2), so as to define at least one passage opening (9) of variable amplitude that allows fluid communication between the inlet (1i) and the outlet (1u); In a 2nd aspect, in accordance with the previous aspect, at least one between the active portion (8) of the flow regulating organ (7) and the int