US 11,867,298 B2
System pressure valve for a hydraulic system of a motor vehicle transmission
Alexander Haberstock, Ravensburg (DE); and Markus Herrmann, Scheidegg (DE)
Assigned to ZF FRIEDRICHSHAFEN AG, Friedrichshafen (DE)
Appl. No. 17/292,230
Filed by ZF Friedrichshafen AG, Friedrichshafen (DE)
PCT Filed Oct. 7, 2019, PCT No. PCT/EP2019/077026
§ 371(c)(1), (2) Date May 7, 2021,
PCT Pub. No. WO2020/094310, PCT Pub. Date May 14, 2020.
Claims priority of application No. 10 2018 219 113.1 (DE), filed on Nov. 9, 2018.
Prior Publication US 2021/0404564 A1, Dec. 30, 2021
Int. Cl. F15B 21/00 (2006.01); F16K 11/07 (2006.01); F15B 13/02 (2006.01)
CPC F16K 11/07 (2013.01) [F15B 13/022 (2013.01); F15B 2211/20576 (2013.01); F15B 2211/4053 (2013.01); F15B 2211/428 (2013.01); F15B 2211/61 (2013.01); F15B 2211/7142 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A system pressure valve (9) for a hydraulic system (4) of a motor vehicle transmission (3), comprising:
a valve housing (71);
a piston rod (11);
a first inlet (8);
a second inlet (10);
a first outlet (72);
a second outlet (73); and
a third outlet (65),
wherein a primary pump (6) of the hydraulic system (4) is connectable to the first inlet (8),
wherein a secondary pump (7) of the hydraulic system (4) is connectable to the second inlet (10);
wherein a primary system pressure circuit (16) of the hydraulic system (4) is connectable to the first outlet (72) and to the second outlet (73),
wherein a secondary system pressure circuit (18) of the hydraulic system (4) is connectable to the third outlet (65),
wherein the system pressure valve (9) is configured for displacing the piston rod (11) within the valve housing (71) into a first switching position, into a second switching position, and into a third switching position,
wherein, in the first switching position, the third outlet (65) is connected neither to the first inlet (8) nor to the second inlet (10),
wherein, in the second switching position, the second inlet (10) is connected to the third outlet (65), and
wherein, in the third switching position, the third outlet (65) is connected to the first inlet (8) as well as to the second inlet (10).