Patent · US Expired

Power tool charging system having battery reconditioning and battery capacity data updating functions

US6191554A · kind A · utility

54Cited by
3References
18Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJul 2, 1999
Grant dateFeb 20, 2001
Priority date
Expiry dateJul 2, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J7/0069
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An improved charging system for preventing battery deterioration and for accurate indication of the remaining battery charge level includes an electric power tool (2) and a charger (1). The electric power tool (2) is provided with an internal rechargeable batteries (6) and a second controller (9). The charger (1) is provided with circuitry for charging, a microcomputer (19), and discharge circuitry which is comprised of a manually-operated battery refreshing button (25), a discharge relay (23) and a discharge resistor (24). Upon depression of the battery refreshing button (25), the microcomputer (19) causes the batteries (6) of the electric power tool (2) to be charged to a full level and discharged to a predetermined level twice. When the two-cycle operation of full charge and discharge is completed, the second controller (9) of the electric power tool (2) updates the remaining charge level of the batteries (6).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.