David F. Winchell has been granted 12 US patents while listed as an inventor at AT&T . The first was granted in 1981 and the most recent in April 2016. David F. Winchell ranks #396,045 of 4,157,543 US inventors in our database (top 9.5%). Patent records list David F. Winchell in Harvard, MA, US.
Patents per Year Patents granted per year, 1981 to 2016 Bar chart with a peak of 4 patents in 1985. peak 4 1981: 1 patents 1981 1984: 3 patents 1984 1985: 4 patents 1985 1987: 3 patents 1987 2016: 1 patents 2016
Issued Patents All Time
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Showing 1–12 of 12 patents
Patent # Title Co-Inventors Date Approx Value ⓘ
9323671 Managing enhanced write caching David W. Harvey , H. Austin Spang, IV , Gregory S. Schaffer 2016-04-26
$10,215,000
4691347 Method and apparatus for controlling a conference Keith R. Stanley 1987-09-01
4653045 Interactive facility control arrangement Keith R. Stanley 1987-03-24
4635251 Meet-me conference with control capabilities Keith R. Stanley 1987-01-06
4550224 Method and apparatus for adding conferees to a conference — 1985-10-29
4544804 Conference control transfer arrangement Diane E. Herr , Laddie E. Suk 1985-10-01
4540850 Method and apparatus for controlling a conference Diane E. Herr , Laddie E. Suk 1985-09-10
4529842 Automatic fault recovery arrangement Jacqueline Levy , Ranjana A. Medhekar 1985-07-16
4479211 Method and apparatus for controlling ports in a digital conference arrangement Ann H. Bass , Jeffery G. Blaschak , Mohamed A. Marouf , Paul W. Vancil 1984-10-23
4475189 Automatic interactive conference arrangement Diane E. Herr , Reinhard Metz , Laddie E. Suk , Paul Wiley 1984-10-02
4460807 Conference routing arrangement Howard A. Kerr 1984-07-17
4305045 Phase locked loop clock synchronizing circuit with programmable controller Reinhard Metz 1981-12-08
$21,622,000