Patent · US Expired

Circuit for firing paystation coin relay using power derived from telephone line tip/ring voltage

US5216707A · kind A · utility

3Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 6, 1991
Grant dateJun 1, 1993
Priority date
Expiry dateAug 6, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D30/70
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Increased power to operate a paystation coin relay is derived from the tip/ring pair by means of a power boost circuit, which is controllably coupled to the tip/ring pair when the coin relay is to be fired. To fire the coin relay, a line coupling relay circuit is energized, so as to apply the tip/ring line voltage to a D.C.-to-D.C. converter, the output of which is coupled to current storage (capacitor) circuit. The output of the current storage circuit is coupled to a first switch circuit and monitored by a comparator. The first switch circuit has an output coupled in circuit with the coin relay. In response to the comparator detecting that the current storage circuit has accumulated sufficient electrical energy to fire the coin relay, the comparator enables the first switch circuit, so that the output of the current storage circuit is applied to the coin relay, thereby firing the coin relay, to either collect accumulated coins or return the coins to the paystation user, depending upon a controllably established coin relay current flow path to the coin relay winding. The output of the comparator is further coupled through a delay circuit to a second transistor switch circuit which…

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