Inventor · disambiguated record
Roger T. Simpson
Also filed as: DUCKLOW DIANE K · SIMPSON ROGER · SIMPSON ROGER T
77 granted patents·8 pending applications·2,839 citations·filing 1982–2015
99Inventor score
Files withBORGWARNER INC58BORG WARNER AUTOMOTIVE20SIMPSON ROGER T5JACOBS VEHICLE SYSTEMS INC1XCP INC1
Top patents by PatentIndex Score
85 records- 0198US6322468B1Pressure relief valve and dual path vent disc for hydraulic tensionerBORGWARNER INC·Filed 1999·Granted Nov 27, 2001·150 cites·20 claims
- 0298US6311655B1Multi-position variable cam timing system having a vane-mounted locking-piston deviceBORGWARNER INC·Filed 2000·Granted Nov 6, 2001·95 cites·19 claims
- 0398US5407024AOn demand vehicle drive systemBORG WARNER AUTOMOTIVE·Filed 1992·Granted Apr 18, 1995·312 cites·79 claims
- 0497US6374787B2Multi-position variable camshaft timing system actuated by engine oil pressureBORGWARNER INC·Filed 2001·Granted Apr 23, 2002·58 cites·23 claims
- 0597US6250265B1Variable valve timing with actuator locking for internal combustion engineBORGWARNER INC·Filed 1999·Granted Jun 26, 2001·73 cites·27 claims
- 0697US5707309AHydraulic tensioner with modular inlet check valve with pressure reliefBORG WARNER AUTOMOTIVE·Filed 1997·Granted Jan 13, 1998·98 cites·19 claims
- 0797US5700213AIntegral inlet and pressure relief valve for an automotive tensionerBORG WARNER AUTOMOTIVE·Filed 1995·Granted Dec 23, 1997·109 cites·20 claims
- 0896US6263846B1Control valve strategy for vane-type variable camshaft timing systemBORGWARNER INC·Filed 2000·Granted Jul 24, 2001·65 cites·23 claims
- 0996US6244981B1Hydraulic tensioner with pawl-style external rackBORGWARNER INC·Filed 1999·Granted Jun 12, 2001·80 cites·17 claims
- 1096US6120402AHydraulic tensioner with external rack having backlash restrictionBORGWARNER INC·Filed 1999·Granted Sep 19, 2000·78 cites·6 claims
- 1196US5967921AHydraulic chain tensioner with molded plastic bodyBORG WARNER AUTOMOTIVE·Filed 1997·Granted Oct 19, 1999·92 cites·10 claims
- 1295US6481402B1Variable camshaft timing system with pin-style lock between relatively oscillatable componentsBORGWARNER INC·Filed 2001·Granted Nov 19, 2002·54 cites·2 claims
- 1395US6283076B1Torsionally compliant sprocket for engine balance shaft drive and method of manufactureBORGWARNER INC·Filed 2000·Granted Sep 4, 2001·51 cites·7 claims
- 1494US6634973B1Hydraulic tensioner with two spring biased pistons and cushioned pull-back rackBORGWARNER INC·Filed 2000·Granted Oct 21, 2003·49 cites·13 claims
- 1594US6571757B1Variable force solenoid with spool position feedback to control the position of a center mounted spool valve to control the phase angle of cam mounted phaserBORGWARNER INC·Filed 2002·Granted Jun 3, 2003·52 cites·16 claims
- 1694US5993342AHydraulic tensioner with force limiting tensioner springBORG WARNER AUTOMOTIVE·Filed 1998·Granted Nov 30, 1999·67 cites·15 claims
- 1793US10006321B2Engine variable camshaft timing phaser with planetary gear setBORGWARNER INC·Filed 2015·Granted Jun 26, 2018·6 cites·15 claims
- 1893US6247434B1Multi-position variable camshaft timing system actuated by engine oilBORGWARNER INC·Filed 1999·Granted Jun 19, 2001·55 cites·23 claims
- 1993US6196939B1Hydraulic tensioner with a hydraulically controlled rackBORGWARNER INC·Filed 1999·Granted Mar 6, 2001·59 cites·8 claims
- 2093US5462493ADual blade chain tensioner with dampingBORG WARNER AUTOMOTIVE·Filed 1994·Granted Oct 31, 1995·51 cites·19 claims
- 2192US10138944B2Electric phaser coupling methodBORGWARNER INC·Filed 2015·Granted Nov 27, 2018·6 cites·15 claims
- 2292US6435154B1VCT controls integrated into front cover of engineBORGWARNER INC·Filed 2001·Granted Aug 20, 2002·33 cites·13 claims
- 2391US6612952B1Blade tensioner having spring blade cantilevered from distal end of armBORGWARNER INC·Filed 1999·Granted Sep 2, 2003·49 cites·23 claims
- 2491US5951423AMechanical friction tensionerBORG WARNER AUTOMOTIVE·Filed 1997·Granted Sep 14, 1999·50 cites·12 claims
- 2589US6234127B1Torsionally compliant and damped sprocket system with position stopsBORGWARNER INC·Filed 1999·Granted May 22, 2001·45 cites·15 claims
- 2689US5485894AOn demand vehicle drive systemBORG WARNER AUTOMOTIVE·Filed 1995·Granted Jan 23, 1996·36 cites·20 claims
- 2788US6117033AHydraulic tensioner with tuned spring pistonBORGWARNER INC·Filed 1999·Granted Sep 12, 2000·41 cites·10 claims
- 2888US5989139AHydraulic tensioner with external rackBORG WARNER AUTOMOTIVE·Filed 1999·Granted Nov 23, 1999·55 cites·8 claims
- 2987US7137371B2Phaser with a single recirculation check valve and inlet valveBORGWARNER INC·Filed 2004·Granted Nov 21, 2006·26 cites·4 claims
- 3087US6631779B2On demand vehicle drive systemBORGWARNER INC·Filed 2001·Granted Oct 14, 2003·39 cites·24 claims
- 3187US6263995B1On demand vehicle drive systemBORGWARNER INC·Filed 1999·Granted Jul 24, 2001·64 cites·20 claims
- 3287US5492194AOn demand vehicle drive systemBORG WARNER AUTOMOTIVE·Filed 1993·Granted Feb 20, 1996·64 cites·20 claims
- 3386US7255077B2CTA phaser with proportional oil pressure for actuation at engine condition with low cam torsionalsBORGWARNER INC·Filed 2005·Granted Aug 14, 2007·10 cites·32 claims
- 3486US6126563AQuick purge tensioner with internal piston springBORGWARNER INC·Filed 1999·Granted Oct 3, 2000·38 cites·8 claims
- 3585US5967920AHydraulic tensioner with a bore cupBORG WARNER AUTOMOTIVE·Filed 1997·Granted Oct 19, 1999·41 cites·8 claims
- 3684US8677849B2Sprocket with damper and compensatorSIMPSON ROGER T·Filed 2009·Granted Mar 25, 2014·11 cites·8 claims
- 3784US6382155B2Variable valve timing with actuator locking for internal combustion engineBORGWARNER INC·Filed 2001·Granted May 7, 2002·19 cites·27 claims
- 3883US5653652AHydraulic tensioning system with dual arm bladeBORG WARNER AUTOMOTIVE·Filed 1995·Granted Aug 5, 1997·34 cites·9 claims
- 3982US5700216AHydraulic tensioner for dual chain systemBORG WARNER AUTOMOTIVE·Filed 1996·Granted Dec 23, 1997·34 cites·5 claims
- 4082US5655416ATorsional absorber for camshaft sprocketsBORG WARNER AUTOMOTIVE·Filed 1996·Granted Aug 12, 1997·32 cites·5 claims
- 4181US6622675B1Dual PWM control of a center mounted spool value to control a cam phaserBORGWARNER INC·Filed 2002·Granted Sep 23, 2003·20 cites·30 claims
- 4280US6139454AHydraulic tensioner with plastic cap check valve or ventBORGWARNER INC·Filed 1999·Granted Oct 31, 2000·30 cites·8 claims
- 4379US8256393B2Variable cam timing controls mounted in the camshaftSIMPSON ROGER T·Filed 2008·Granted Sep 4, 2012·6 cites·6 claims
- 4479US6840202B2Method to reduce noise of a cam phaser by controlling the position of center mounted spool valveBORGWARNER INC·Filed 2003·Granted Jan 11, 2005·16 cites·8 claims
- 4579US6062330AOn demand vehicle drive systemBORG WARNER AUTOMOTIVE·Filed 1997·Granted May 16, 2000·40 cites·43 claims
- 4677US6623390B2Hydraulic tensioner with pivotal mountBORGWARNER INC·Filed 2001·Granted Sep 23, 2003·14 cites·19 claims
- 4773US5609219AOn demand vehicle drive systemBORG WARNER AUTOMOTIVE·Filed 1995·Granted Mar 11, 1997·38 cites·23 claims
- 4873US5579665ATorsional absorber for camshaft sprocketsBORG WARNER AUTOMOTIVE·Filed 1995·Granted Dec 3, 1996·23 cites·8 claims
- 4972US7214153B2Method of changing the duty cycle frequency of a PWM solenoid on a CAM phaser to increase compliance in a timing driveBORGWARNER INC·Filed 2003·Granted May 8, 2007·14 cites·8 claims
- 5071US7497297B2On demand vehicle drive systemBORGWARNER INC·Filed 2003·Granted Mar 3, 2009·14 cites·33 claims
Showing the top 50 of 85 patent records by PatentIndex Score.
Join the waitlist — get patent alerts
Get an alert when Roger T. Simpson files or is granted a new patent.
We store only your email — no account needed. See our privacy policy.
Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →