Automotive electric liquid pump

Abstract

An automotive electric liquid pump includes a pumping section with a pump rotor, a motor section axially aligned with the pumping section, an electronics cooling circuit, a rotor shaft, and a pump cover housing part. The motor section has a motor control electronics which drives a dry electromagnetic motor stator, and a wet permanently-magnetized motor rotor separated therefrom via a separation wall. The electronics cooling circuit cools the motor control electronics. The rotor shaft supports the pump rotor and the motor rotor, is part of the internal electronics cooling circuit, and is provided as an axial liquid pipe with a motor-sided axial shaft opening and a pump-sided shaft axial opening. The pump cover housing part is mounted to a pump housing and has a throttle groove providing a fluid connection between the axial opening and a static low-pressure pump inlet chamber or with a static high-pressure pump outlet chamber.

1 - 9 . (canceled) 
     
     
         10 . An automotive electric liquid pump for providing a pressurized pumping liquid, the automotive electric liquid pump comprising:
 a positive displacement pumping section comprising a pump rotor which is arranged within a pump chamber which is substantially defined by a pump main housing;   a motor section which is arranged in an axial alignment with the positive displacement pumping section, the motor section comprising,
 a dry electromagnetic motor stator, 
 a motor control electronics which is configured to drive the dry electromagnetic motor stator, and 
 a wet permanently-magnetized motor rotor which is separated from the dry electromagnetic motor stator via a separation wall which is substantially cylindrical; 
   an internal electronics cooling circuit which is configured to actively cool the motor control electronics with the pressurized pumping liquid;   a rotor shaft which is configured to co-rotatably support the pump rotor and the wet permanently-magnetized motor rotor, the rotor shaft being arranged as an axial liquid pipe comprising a motor-sided axial shaft opening and a pump-sided shaft axial opening, the axial liquid pipe being a part of the internal electronics cooling circuit; and   a separate axial pump cover housing part which is axially mounted to the pump main housing and which comprises a proximal throttle groove which provides a fluid connection between the pump-sided shaft axial opening and a static low-pressure pump inlet chamber or with a static high-pressure pump outlet chamber.   
     
     
         11 . The automotive electric liquid pump as recited in  claim 10 , wherein the proximal throttle groove defines a narrowest cross section of the internal electronics cooling circuit. 
     
     
         12 . The automotive electric liquid pump as recited in  claim 11 , wherein the narrowest cross section of the proximal throttle groove is smaller than 5 mm 2 . 
     
     
         13 . The automotive electric liquid pump as recited in  claim 10 , wherein the proximal throttle groove has an orientation with is substantially radial. 
     
     
         14 . The automotive electric liquid pump as recited in  claim 10 , wherein the proximal throttle groove is covered by the pump rotor. 
     
     
         15 . The automotive electric liquid pump as recited in  claim 10 , wherein the separate axial pump cover housing part at least one of,
 defines a pump chamber inlet opening and the static low-pressure pump inlet chamber corresponding thereto, and   defines a pump chamber outlet opening and the static high-pressure pump outlet chamber corresponding thereto.   
     
     
         16 . The automotive electric liquid pump as recited in  claim 10 , wherein the positive displacement pumping section defines a Gerotor-type pump comprising the pump rotor and an additional pump rotor which cooperate with each other. 
     
     
         17 . The automotive electric liquid pump as recited in  claim 10 , wherein,
 the wet permanently-magnetized motor rotor is arranged in a motor rotor chamber which is axially closed by a bottom wall, and   the motor control electronics comprises power semiconductors which are arranged to be in a direct thermal contact with the bottom wall.   
     
     
         18 . The automotive electric liquid pump as recited in  claim 10 , wherein the pressurized pumping liquid is oil.