Inventor · Eugene, OR, US

Ray A. Walker

21Patents
11h-index
20Co-inventors
75Inventor score

Filing activity: Jun 8, 1977 → Dec 13, 2018

Most-cited inventions

PatentTitleAreaCited byStatus
US5883370A Automated method for filling drug prescriptions Physics 289 Expired
US6312106A Method and apparatus for transferring information between a replaceable consumable and a printing device Performing Operations; Transporting 125 Expired
US6302527A Method and apparatus for transferring information between a printer portion and a replaceable printing component Physics 98 Expired
US6312074A Method and apparatus for detecting fluid level in a fluid container Performing Operations; Transporting 97 Expired
US4129384A Optical extensometer Physics 65 Expired
US6648434B2 Digitally compensated pressure ink level sense system and method Performing Operations; Transporting 53 Expired
US6274880A Fluid level sensing system and method having controlled surface pairs Performing Operations; Transporting 22 Expired
US6345891B1 Method and apparatus for specifying ink volume in a multichamber ink container Performing Operations; Transporting 16 Expired
US6929343B2 Fluid detection system Performing Operations; Transporting 14 Expired
US5327451A Laser diode assembly for laser scanner system Electricity 14 Expired
US6494562B1 Method and apparatus for identifying a sales channel Physics 13 Expired
US6513901B1 Method and apparatus for determining drop volume from a drop ejection device Performing Operations; Transporting 10 Expired
US6863377B2 Method and apparatus for identifying a sales channel Physics 9 Expired
US6431672B1 Ink container having dual capillary members with differing capillary pressures for precise ink level sensing Performing Operations; Transporting 6 Expired
US6676240B2 Method and apparatus for transferring information between a replaceable consumable and a printing device Performing Operations; Transporting 6 Expired
US6247775A Method and apparatus for detecting ink level Performing Operations; Transporting 6 Expired
US4690556A Capillary bore straightness inspection Physics 6 Expired
US6739691B2 Method and apparatus for preventing theft of replaceable printing components Physics 3 Expired
US6685298B2 Method and apparatus for preventing theft of replaceable printing components Physics 2 Expired
US7110127B2 Method and apparatus for product regionalization Performing Operations; Transporting 2 Expired
US10867002B1 Real estate search interface and method Physics 0 Active

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.