US 11,788,644 B2
Proportional valve, electric shower incorporating the proportional valve and tap incorporating same
Michael Quinn, Surrey (GB); and Anton Stefanic, Suhor (SI)
Assigned to Hydralectric Group Ltd, Surrey (GB); and EKI D.O.O., Crnomelj (SI)
Appl. No. 15/532,545
Filed by Hydralectric Group Ltd, Surrey (GB); and EKI D.O.O., Crnomelj (SI)
PCT Filed Dec. 2, 2015, PCT No. PCT/GB2015/053680
§ 371(c)(1), (2) Date Jun. 2, 2017,
PCT Pub. No. WO2016/087849, PCT Pub. Date Jun. 9, 2016.
Claims priority of application No. 1517469 (GB), filed on Oct. 2, 2015.
Prior Publication US 2017/0363224 A1, Dec. 21, 2017
Int. Cl. F16K 31/40 (2006.01); G05D 7/00 (2006.01)
CPC F16K 31/404 (2013.01) [G05D 7/005 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A proportional valve comprising:
an input port and an output port;
a diaphragm provided between the input port and the output port,
a diaphragm plate mounted to the diaphragm, the diaphragm plate having a pilot orifice formed therethrough;
a solenoid comprising an armature and a field winding, the armature being movable in a first direction response to a magnetic field generated by the field winding,
biasing means arranged to provide a biasing force to the armature in a direction opposite to said first direction, wherein in the absence of current in the solenoid, the biasing force is arranged to urge the armature to position the diaphragm plate in a main orifice between the input port and the output port to block the flow of fluid therebetween, with the armature blocking the pilot orifice,
wherein movement of the armature in said first direction in response to a magnetic field generated by the field winding opens the pilot orifice to allow fluid to flow therethrough, and allows the diaphragm plate to move out of the main orifice to create a gap therebetween allowing flow of fluid from the input port to the output port,
wherein said biasing means is arranged to exert a variable force on the armature over at least part of its travel,
wherein said biasing means includes at least two coiled compression springs, with one configured to sit axially within the other, and
wherein said at least two springs are arranged to exert a biasing force on the armature at different stages during the travel of the armature.