Multiple lobe vane fluid pump having enhanced under-vane cavity pressurization

Abstract

A multiple lobe vane fluid pump having enhanced under-vane cavity pressurization for cold start priming includes a pressure plate having a first flow passage and a second flow passage, the first flow passage being configured to allow fluid flow between a primary under-vane cavity and a primary discharge port, the second flow passage being configured to allow fluid flow between the primary discharge port and a secondary under-vane cavity. Additionally, the pump includes a thrust plate including the primary under-vane cavity, a first adjacent under-vane cavity having one open end in fluid communication with a first end on the primary under-vane cavity, and a second adjacent under-vane cavity having one open end in fluid communication with a second end of the primary under-vane cavity.

What is claimed is: 
     
         1 . A multiple lobe vane fluid pump having enhanced under-vane cavity pressurization for cold start priming comprising:
 a pressure plate having a first flow passage and a second flow passage, the first flow passage being configured to allow fluid flow between a primary under-vane cavity and a primary discharge port, the second flow passage being configured to allow fluid flow between the primary discharge port and a secondary under-vane cavity; and   a thrust plate including the primary under-vane cavity, a first adjacent under-vane cavity having one open end in fluid communication with a first end of the primary under-vane cavity, and a second adjacent under-vane cavity having one open end in fluid communication with a second end of the primary under-vane cavity.   
     
     
         2 . The pump of  claim 1  further comprising each of the first and second adjacent under-vane cavities being aligned with inward radial vane motion caused by a multiple lobe cam profile during rotor rotation. 
     
     
         3 . The pump of  claim 1  wherein the first flow passage is configured to be a predetermined smaller size than the second flow passage. 
     
     
         4 . The pump of  claim 3  wherein the first flow passage is less than half the size of the second flow passage. 
     
     
         5 . The pump of  claim 3  wherein the first flow passage is less than or equal to one third the size of the second flow passage. 
     
     
         6 . A multiple lobe vane fluid pump having enhanced under-vane cavity pressurization for cold start priming comprising:
 a pressure plate having a first flow passage and a second flow passage, the first flow passage being configured to allow fluid flow between a primary under-vane cavity and a primary discharge port, the second flow passage being configured to allow fluid flow between the primary discharge port and a secondary under-vane cavity; and   a thrust plate including the primary under-vane cavity, a first adjacent under-vane cavity having one open end in fluid communication with a first end on the primary under-vane cavity, and a second adjacent under-vane cavity having one open end in fluid communication with a second end of the primary under-vane cavity, wherein each of the first and second adjacent under-vane cavities being aligned with inward radial vane motion caused by a multiple lobe cam profile during rotor rotation.   
     
     
         7 . The pump of  claim 6  wherein the first flow passage is configured to be a predetermined smaller size than the second flow passage. 
     
     
         8 . The pump of  claim 7  wherein the first flow passage is less than half the size of the second flow passage. 
     
     
         9 . The pump of  claim 7  wherein the first flow passage is less than or equal to one third the size of the second flow passage. 
     
     
         10 . A multiple lobe vane fluid pump having enhanced under-vane cavity pressurization for cold start priming comprising:
 a pressure plate having a first flow passage and a second flow passage, the first flow passage being configured to allow fluid flow between a primary under-vane cavity and a primary discharge port, the second flow passage being configured to allow fluid flow between the primary discharge port and a secondary under-vane cavity, wherein the first flow passage is configured to be a predetermined smaller size than the second flow passage; and   a thrust plate including the primary under-vane cavity, a first adjacent under-vane cavity having one open end in fluid communication with a first end on the primary under-vane cavity, and a second adjacent under-vane cavity having one open end in fluid communication with a second end of the primary under-vane cavity, wherein each of the first and second adjacent under-vane cavities being aligned with inward radial vane motion caused by a multiple lobe cam profile during rotor rotation.   
     
     
         11 . The pump of  claim 10  wherein the first flow passage is less than half the size of the second flow passage. 
     
     
         12 . The pump of  claim 10  wherein the first flow passage is less than or equal to one third the size of the second flow passage.