Patent · US Expired

Tamper-evident electronic combination lock having integral bearing/retaining member

US5647235A · kind A · utility

21Cited by
31References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 27, 1995
Grant dateJul 15, 1997
Priority date
Expiry dateApr 27, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/869
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A user of a self-powered electronic combination lock rotates an outer dial to cause generators to generate energy for storage in a capacitor bank. The user then rotates an inner dial to cause a microcontroller to sequentially display a combination of numbers, and presses the inner dial to select a displayed number. The microcontroller determines direction and extent of motion of the inner dial by receiving signals derived from Wiegand sensors placed in proximity to a magnetized disc which rotates integrally with the inner dial, and controls the display of numerals on an LCD display accordingly. When the microcontroller determines that a correct combination has been entered, it activates a motor to move a motor cam to act directly on a locking lever so that the locking lever can engage a drive cam integrally linked with the inner dial, to allow the inner dial to withdraw the lock's bolt. Software features, as well as power level monitoring features, cause the locking lever to be moved away from the drive cam to prevent the bolt from being withdrawn if it has not already been withdrawn within a given time window. Integral bearing/retaining members make the lock dials tamper-evident. …

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