Coin telephone control circuit
AssigneeBell Telephone Laboratories, Incorporated
InventorLanny S. Smoot
Life of this patent
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Abstract
Coins deposited in a coin telephone are collected or refunded by selectively discharging one of a plurality of capacitors (10,12) through a current limiter (46) for a period just long enough to operate the coin control relay (38) in the telephone. Use of this current limiter minimizes the drain of power from the remote terminal of a subscriber loop carrier system which derives all of its power from a telephone central office. A second current limiter (24) limits the rate at which the capacitors are charged.
Claims9
A coin telephone control circuit CHARACTERIZED BY
- means for providing a constant current pulse to effect collection or refund of coins in said coin telephone (38), said means including
- a plurality of capacitors (10, 12) connected in parallel for storing energy.
A coin telephone control circuit for collecting or refunding coins, said circuit comprising
- a plurality of capacitors (10,12),
- means (30,32,34,36,20,22) for selectively discharging said capacitors one at a time through said coin telephone,
- means (46) for limiting the flow of discharge current through said coin telephone,
- means (24) for limiting the current for charging said capacitors, and
- means (16,18) for preventing the discharge of said capacitors below a threshold value.
Dependencies are inferred from the claim text.