US 12,435,812 B2
Pilot controlled solenoid valve
Søren Støttrup Kristensen, Horsens (DK); and Varun Venugopalan Potti, Nordborg (DK)
Assigned to DANFOSS A/S, Nordborg (DK)
Appl. No. 18/574,176
Filed by Danfoss A/S, Nordborg (DK)
PCT Filed Jun. 30, 2022, PCT No. PCT/EP2022/068141
§ 371(c)(1), (2) Date Dec. 26, 2023,
PCT Pub. No. WO2023/275289, PCT Pub. Date Jan. 5, 2023.
Claims priority of application No. 202111029478 (IN), filed on Jun. 30, 2021.
Prior Publication US 2024/0288090 A1, Aug. 29, 2024
Int. Cl. F16K 31/40 (2006.01)
CPC F16K 31/408 (2013.01) 20 Claims
OG exemplary drawing
 
1. A pilot controlled solenoid valve comprising a housing having an inlet and an outlet, a valve seat between inlet and outlet, a valve element cooperating with the valve seat, and a solenoid arrangement having a coil and a movable armature, wherein the valve element is arranged between an inlet chamber connected to the inlet and a pilot pressure chamber and comprises a pilot channel extending from the pilot pressure chamber to the outlet, wherein the movable armature opens and closes an opening of the pilot channel into the pilot pressure chamber depending on magnetic forces produced by the coil, wherein pressure decreasing means are provided for decreasing a pressure in the pilot pressure chamber below a pressure downstream the valve seat when the valve element is lifted off from the valve seat, wherein the pressure decreasing means are driven by a flow of a fluid from the inlet to the outlet controlled by the valve and are in form of a flow restriction in fluid connection with the pilot pressure chamber, wherein the flow restriction is provided in addition to a flow restriction formed between valve element and valve seat, wherein the flow restriction comprises a protrusion of the valve element protruding into the valve seat when the valve element is lifted a distance off the valve seat and a ring gap which is formed between the protrusion and an inner wall of the outlet in a fully open condition of the valve, wherein a width of the ring gap is smaller than the lift off distance between the valve element and the valve seat in the fully open condition of the valve, so that the area of the flow restriction in fluid connection with the pilot pressure chamber through which the fluid controlled by the valve can pass is the smallest one on the way from the inlet to the outlet; and that the valve comprises a second movable armature, wherein the movable armature and the second movable armature are arranged within a tube, wherein a spring is arranged between the two movable armatures, wherein the second movable armature is loaded by a second spring arranged between the second movable armature and a bottom of the tube, and wherein two pins are arranged between the second movable armature and the valve element for keeping a distance between the second movable armature and the valve element constant.