Patent assignee · US · COMPANY

Curtis Instruments, Inc.

48Patents
11Active
48Granted
46Portfolio score

Filing activity: Jan 3, 1975 → Sep 12, 2022 · 2 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US5451881A Method and means for adjusting battery monitor based on rate of current drawn from the battery Emerging Cross-Sectional Technologies 263 Expired
US4514694A Quiescent battery testing method and apparatus Emerging Cross-Sectional Technologies 202 Expired
US4012681A Battery control system for battery operated vehicles Emerging Cross-Sectional Technologies 131 Expired
US4193026A Method and apparatus for measuring the state of charge of a battery by monitoring reductions in voltage Physics 111 Expired
US4560937A Battery state of charge metering method and apparatus Physics 69 Expired
US6611116B2 Anti-spin control for a separately excited motor drive system Emerging Cross-Sectional Technologies 64 Expired
US4460870A Quiescent voltage sampling battery state of charge meter Emerging Cross-Sectional Technologies 57 Expired
USD387333S Heatsink enclosure for an electrical controller General 50 Expired
US4017724A Apparatus for measuring battery depletion by monitoring reductions in voltage Physics 36 Expired
US4626750A Solid state d.c. motor control Emerging Cross-Sectional Technologies 36 Expired
US4388618A Battery state of charge indicator operating on bidirectional integrations of terminal voltage Emerging Cross-Sectional Technologies 34 Expired
US9046559B2 Isolation monitor Emerging Cross-Sectional Technologies 33 Active
US4186339A Method and apparatus for measuring current, especially useful in multi-ampere systems Physics 30 Expired
US4740754A Bidirectional battery state-of-charge monitor Emerging Cross-Sectional Technologies 29 Expired
US6439067B1 Shaft sensor assembly for angular velocity, torque, and power Physics 29 Expired
US5247253A Eddy current proximity sensing means and method useful for determining throttle position Electricity 23 Expired
US4712195A Solid-state cumulative operations measurement system Physics 20 Expired
US4728923A Steerable wheel direction indicator Emerging Cross-Sectional Technologies 15 Expired
US4724332A Synchronous load lock-out control system for battery powered equipment Electricity 15 Expired
US4288734A Bidirectional integrator Emerging Cross-Sectional Technologies 15 Expired
US5261025A Method and apparatus for DC motor speed control Emerging Cross-Sectional Technologies 14 Expired
US6208245A Engine oil change indicator system Mechanical Engineering; Lighting; Heating 13 Expired
US6456043B1 Method of diagnosing the state of health of a battery Electricity 13 Expired
US4139896A Method and apparatus for producing nonlinear integral functions Physics 12 Expired
US6181106A Sequential high-rate charging of battery cells Emerging Cross-Sectional Technologies 11 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.