By-pass solenoid with integral check valve
AssigneeEaton Corporation
InventorCarl G. Gluf, Jr.
Life of this patent
Estimating the term…
Abstract
A by-pass solenoid (32) with an integral check valve assembly (36) for by-passing excess pump (16) fluid flow. The integral check valve assembly (36) positioned in a first chamber (120) of a valve sub-assembly (52) allows fluid flow from an inlet (34) to an outlet port (40) in a normal mode of operation. Upon actuation of the solenoid sub-assembly (50), the by-pass solenoid (32) diverts excess fluid flow to a by-pass port (42) for re-circulation during periods when fluid flow demand is low and still maintains a fairly constant system pressure. Check valve assembly (36) prevents re-circulated fluid from directly entering the working hydraulic circuit and maintains system pressure. The present invention advantageously provides a compact integral fluid flow control device for bleeding excess pump flow.
Claims20
A by-pass solenoid (32), comprising:
- a solenoid sub-assembly (50) having a movable armature (70) constructed to translate with respect to an electrical coil (64) in response to a change in an electrical signal being applied to said electrical coil (64);
- and
- a valve sub-assembly (52), said valve sub-assembly (52) including a valve body (116) coupled to said solenoid sub-assembly (50) and receiving a poppet valve member (78) translatable with said armature (70),
- said valve body (116) having at least an inlet port (34), an outlet port (40), and a by-pass port (42) therein, said valve body (116) having a stepped bore (118) extending therethrough, said stepped bore (118) being fluidly connected to said inlet port (34), said outlet port (40), and said by-pass port (42), said stepped bore (118) having at least a first chamber (120) fluidly connected to said inlet port (34) and said outlet port (40), said valve sub-assembly (52) further including a check valve assembly (36) disposed within said first chamber (120), said check valve assembly (36) being constructed to fluidly communicate with said inlet port (34), said outlet port (40), and said by-pass port for selectively discharging fluid from a desired port of said valve sub-assembly (52).
A hydraulic system (10) for by-passing pump flow, comprising:
- pump means (16) having at least a first and a second pumping element (17, 18), each pumping element having an inlet (19, 20) and an outlet (22, 24), said first and second inlets (19, 20) receiving hydraulic fluid from a system reservoir (26), said first pumping element (17) directing the hydraulic fluid to the first outlet (22), said second pumping element (18) directing the hydraulic fluid to the second outlet (24);
- a by-pass solenoid (32) having an inlet port (34) fluidly connected to said first outlet (22) of said pump means (16) for receiving hydraulic fluid therefrom, said by-pass solenoid (32) further having an outlet port (40) fluidly connected to said second outlet (24), said by-pass solenoid (32) further having a check valve assembly (36) situated in a first chamber (120) therein and constructed to receive flow of hydraulic fluid therethrough in a de-energized position of said by-pass solenoid (32) and discharge the hydraulic fluid to an outlet port (40), said check valve assembly (36) being further constructed to allow hydraulic fluid flow through the check valve assembly (36) to a by-pass port (42) upon actuation of said by-pass solenoid (32);
- and
- a controller (14) in electrical communication with said by-pass solenoid (32) for actuating said solenoid (32) from the de-energized position to the energized position to re-direct flow of hydraulic fluid out from the by-pass solenoid by-pass port (42) for re-circulation.
A method for regulating excess flow of hydraulic fluid in a hydraulic circuit (12), comprising the steps of:
- supplying hydraulic fluid to a first and second pumping element (17, 18) of pump means (16), each pumping element having an inlet (19, 20) and an outlet (22, 24);
- pumping the hydraulic fluid from the first and second outlet (22, 24) of the pump means (16);
- connecting an inlet port (34) of a by-pass solenoid (32) to the first outlet (22) of the pump means (16) for receiving hydraulic fluid therefrom;
- connecting an outlet port (40) of the by-pass solenoid (32) to the second outlet (24) of the pump means for discharging hydraulic fluid therethrough;
- providing a check valve assembly (36) within a first chamber (120) of the by-pass solenoid (32), the check valve assembly (36) being fluidly connected to the inlet port (34) and the outlet port (40) of the by-pass solenoid (32);
- providing a by-pass port (42) in the by-pass solenoid valve (32) capable of being fluidly connected to the inlet port (34) through the check valve assembly (36) upon actuation of the by-pass solenoid (32);
- directing the hydraulic fluid from the first outlet (22) into the inlet port (34) of the by-pass solenoid (32) through the check valve assembly (36) and out through the outlet port (40);
- and
- actuating the by-pass solenoid (32) to re-direct excess hydraulic fluid through the by-pass port (42) of the by-pass solenoid (32) to a selected location (20, 26).
Dependencies are inferred from the claim text.