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EP-4741670-A1 - DISTRIBUTOR AND OLEODYNAMIC BRAKING SYSTEM OF AN AGRICULTURAL OR FORESTRY VEHICLE

EP4741670A1EP 4741670 A1EP4741670 A1EP 4741670A1EP-4741670-A1

Abstract

Hydraulic distributor, in particular of an agricultural or forestry machine or other mobile industrial means, having an inlet (I) connectable to a pressurized oil delivery (P); a first outlet (U1) connectable to a first user (TB); a second outlet (U2) connectable to a second user (EF); a first gap (L1) connectable to a storage unit (A); a second gap (L2) connectable to a signal (LS); wherein, the distributor (1) has a first valve (V1) which is configured to selectively put in fluidic communication the inlet (I) with the second outlet (U2) and/or the storage unit (A); wherein the inlet (I1) and the first outlet (U1) are always in fluid communication by means of a first conduit (4).

Inventors

  • MAMEI, ENRICO
  • MAMEI, ANDREA

Assignees

  • Slanzi Oleodinamica S.r.l.

Dates

Publication Date
20260513
Application Date
20251107

Claims (10)

  1. Hydraulic distributor, in particular of an agricultural or forestry machine or other mobile industrial means, having an inlet (I) connectable to a pressurized oil delivery (P) and to a priority user (TB); a second outlet (U2) connectable to a second user (EF); a first gap (L1) connectable to a storage unit (A); a second gap (L2) connectable to a first pressure signal (LS) from the primary user (TB); wherein, the distributor comprises a first valve (V1), selectively movable between at least: - a first position (S1) in which the inlet (I) is in communication with the first gap (L1) and the second gap (U2) is closed; and - a second position (S4) in which the second gap (U2) is connected to the inlet (I) and the first gap (L1) is closed; wherein the distributor is characterized in that the first valve (V1) is moved: - in the first configuration (S1) by an elastic element (M1) and by a first actuator (D2) fed by the oil pressure to the second gap (L2); and, - in the second position (S4) by a second actuator (D1) fed by the oil pressure to the inlet (I).
  2. Distributor according to claim 1, wherein the first valve (V1) has a conduit (6) connectable to a second recharging valve (V2), which is configured to feed the storage unit (A) during use; wherein, the first valve (V1) is movable into a third position (S3), which is interposed between said first position (S1) and second position (S4); wherein: - in the first position (S1) the communication with the conduit (6) is closed; - in the third position (S3) the first valve (V1) puts in communication the pressurized oil at the inlet (I) with said conduit (6) and closes both the first gap (L1) and the second gap (U2); - in the second position (S4) the conduit (6) communicates with the inlet (I); wherein the first actuator (D2) is fed by a pressure signal that is the greater between the first pressure signal (LS) from the priority user (TB) and a second pressure signal from the second valve (V2).
  3. Distributor according to claim 2, and comprising a body (3) inside which the first valve (V1), the second valve (V2) and a third valve (V3) are made, which is configured to generate, in use, a pressure signal corresponding to the maximum pressure between said first signal (LS) and second signal; wherein the second valve (V2) is configured to recharge the storage unit (A) which is connected, in use, to the first gap (L1).
  4. Distributor according to claim 3 and having a second conduit (7), which connects the first valve (V1) with the storage unit (A); wherein, the distributor comprises a fourth unidirectional valve (V4), which is installed along said second conduit (7) and allows the oil to flow only from the storage unit (A) towards the first valve (V1).
  5. Distributor according to any one of the preceding claims, wherein the pressurized oil delivery (P) and the primary user (TB) communicate with each other through the body (3) of the distributor itself; wherein, the body (3) of the distributor has the inlet (I), a third outlet (U1), and a third conduit (4), which directly connects the inlet (I) and the third outlet (U1) to each other.
  6. Distributor according to any one of claims 3 to 5, wherein the second user (EF) is open-centre.
  7. Distributor according to any one of claims 3 to 5, wherein the second user (EF) is closed-centre and the pressurized oil delivery (P) has a variable flow rate.
  8. Distributor according to any one of claims 3 to 7, wherein the second valve (V2) is configured to feed one or more further storage units (A2).
  9. Distributor according to claim 2, wherein the primary user (TB) is a trailer brake valve.
  10. Hydraulic system, in particular of an agricultural or forestry machine or other mobile industrial means, comprising a hydraulic distributor as claimed in any of the preceding claims.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims priority from Italian patent application no. 102024000025029 filed on November 7, 2024, the entire disclosure of which is incorporated herein by reference. FIELD OF THE ART The present invention relates to a distributor and a hydraulic system, in particular for agricultural, forestry or other mobile industrial means. PRIOR ART It is known to feed, in particular on board an agricultural machine, one or more users with the same delivery of pressurized fluid. It is also known to selectively convey the excess flow rate of the delivery from one user, referred to as the main user, to a further user, referred to as the secondary user. Generally, on board an agricultural or forestry machine, the incoming oil flow rate is generated by fixed displacement hydraulic pumps that are dimensioned so as to be able to ensure the necessary pressure even under the most extreme conditions of use. Therefore, during operation moments of excess oil flow rate are created. The distributors and systems of known type have the disadvantage of being subject to fluctuations in the inlet flow rate, as a function of the flow rate of the inlet delivery. In other words, the known distributors and systems do not guarantee delivery pressure stability. DISCLOSURE OF THE INVENTION Aim of the present invention is to provide a distributor and a hydraulic system of an improved type. According to the present invention a distributor and a hydraulic system are provided as recited in the appended claims. The dependent claims define particular embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS In the following, an embodiment of the invention is described for a better understanding thereof by way of nonlimiting example and with reference to the accompanying drawings, wherein: Figure 1 is a schematic view, with some parts removed for the sake of clarity, of a distributor according to the present invention;Figure 2 shows is a diagram, simplified and with some parts removed for the sake of clarity, of a system according to the present invention;Figure 3 shows a variant of the diagram of Figure 2;Figure 4 shows a further variant of the diagram of Figure 2;Figures 5 to 7 are diagrams of respective different variants of a distributor according to the present invention. EMBODIMENTS OF THE INVENTION In Figure 1, reference numeral 1 is used for a hydraulic distributor, in particular for an agricultural or forestry machine (of known type and not shown). The distributor 1 is a component of a hydraulic system 2. Figure 2 shows the diagram of an embodiment of the hydraulic system 2 of an agricultural or forestry machine comprising a distributor 1 according to the present invention. In particular, the hydraulic system 2 comprises a pressurized oil delivery P, a discharge T and the distributor 1 which is configured, as will be better shown below, to send pressurized oil to: a main user TB, a secondary user EF; and a storage unit A. Preferably the secondary user EF is open-centre. In particular, the distributor 1 has: an inlet I connectable (in a known and schematically shown manner) to the delivery P; a main outlet U1 connectable (in a known and schematically shown manner) to the main user TB; and a secondary outlet U2 connectable to the secondary user EF. The distributor 1 has: a main gap L1 connectable (in a known and schematically shown manner) to the storage unit A, as will be better shown below; a signal gap L2 connectable (in a known and schematically shown manner) to a signal LS; a measurement gap L3 connectable (in a known and schematically shown manner) to a pressure gauge GA. Advantageously, the pressure gauge GA checks the oil pressure inside the storage unit A. The distributor 1 comprises a body 3 inside which chambers and conduits for the passage of oil and the housing of valves are made, as will be shown. According to what is shown in Figure 2, the inlet I is directly connected, through the body 3, with the main outlet U1. In particular, the body 3 of the distributor 1 has a delivery conduit 4 that directly connects the inlet I with the main outlet U1. In this way, advantageously, the pressurized oil is fed directly from the delivery P to the main user TB. The body 3 of the distributor 1 also has a conduit 5. The delivery conduit 4 and the conduit 5 are in fluid communication with each other at a node N1. The conduit 5 puts in communication the secondary user EF with the delivery conduit 4. The distributor 1 further comprises a main valve V1 which is interposed along the conduit 5, as will be better shown below. The distributor 1 has a conduit 6 which connects the main valve V1 with the storage unit A. The distributor 1 comprises a recharging valve V2 interposed along the conduit 6 between the main valve V1 and the storage unit A. The recharging valve V2 comprises an actuator D3 which is driven by the pressurized oil of the storage unit A. The distributor 1 has a conduit 7