Supplying a charging current by way of telephone lines or the like

• US 3,870,822 A
• Filed: 02/14/1972
• Issued: 03/11/1975
• Est. Priority Date: 02/16/1971
• Status: Expired due to Term

• Current Assignee: Oliver Charles Matthews
• Original Assignee: Oliver Charles Matthews
• Inventors: Matthews, Oliver Charles
• Primary Examiner(s): Blakeslee, Ralph D.
• Application Number:
  US05/225,902
• Time in Patent Office: 1,121 Days
• Field of Search: 179/2.5R,4,26 340/310
• US Class Current: 379/413
• CPC Class Codes: H04M 19/08 with current supply sources at the substations generating ringing current H04M19/04

Abstract

The invention provides a power supply at a point remote from a control power source by way of a telephone line. The remote power supply is generally derived from a rechargeable battery, although direct supply to the utilising device is possible. The battery charging current is only supplied to the line when it is in an '"'"''"'"''"'"''"'"'idle'"'"''"'"''"'"''"'"' state. This idle state is sensed at the power transmitter and receiver (central and remote points) and the charging source and chargeable source are then coupled to the line. The invention does not cause degradation of the normal communication circuit as there is atmospheric disconnection of the charging circuit impedance when a '"'"''"'"''"'"''"'"'busy'"'"''"'"''"'"''"'"' condition is sensed for the line.

Claims

1. A power supply system for supplying current from an electrical direct current power source to an auxiliary load at a remote location by way of a telecommunication transmission line, said system including a power transmit unit and a line power receiver unit situated at the location remote from the transmit unit;

said transmit unit including first means to sense the state of communication and to connect, and to disconnect, the power source to, and from, the line, when the line is idle, and busy, respectively, said connection being made at the end of a first predetermined time interval from the line becoming idle, and said disconnection being made when the line is busied; and

, said receiver unit including second means to sense the idle, and busy state of communication, and arranged to connect the load to the line when the line is idle and to cause the current from the power source to flow at the end of a second predetermined time interval from the line becoming idle, and said second means being arranged to disconnect the load from the line when the line is busied and required as a telecommunication lInk.

2. A receiver unit for a power supply system arranged to receive current supplied by way of a telecommunication transmission line, from an electrical direct current power source to an auxiliary load, said receiver unit comprising a second sensing means to sense the idle, and busy state of communication, and a second switch means arranged to connect the load to the line when the line is idle and to cause the current from the power source to flow at the end of a second predetermined time interval, set by a second timing means from the line becoming idle, and said second switch means being arranged to disconnect the load from the line when the line is busied and required as a telecommunication link.

3. A receiver unit as claimed in claim 2 in which the second timing means consists of a second circuit arrangement including a capacitor coupled to a voltage controlled semi-conductor switch and arranged to provide the said second predetermined time interval between 60 and 80 seconds.

4. A receiver unit as claimed in claim 3 in which the receiver unit is connected to the line by way of a bridge rectifier circuit.

5. A method of charging, by way of a telecommunication transmission line, a rechargeable battery at a location in a communication system remote from an electrical direct current power source, so that, during normal communications using the line, the charging current is terminated and the impedance of the communication channel is made independent of any apparatus used in charging the battery, said method comprising:

sensing whether the line is in a busy or idle state;

operating a first switch associated with the power source and arranged to connect the line either to calling equipment, or to the power source, dependent upon the sensed busy, or idle, state, respectively; and

operating a second switch associated with the remote location and arranged to disconnect from, or to connect to, the line, the battery, dependent upon the sensed busy or idle state respectively.

6. A power supply system as claimed in claim 1 in which the power transmit unit comprises a first sensing means to sense the state of communication of the line, and first switch means to connect, and to disconnect, the power source, to and from, the line, when the line is idle, and busy, respectively, said connection being made at the end of a first predetermined time interval, set by a first timing means, from a line becoming idle, and said disconnection being made when the line is busied.

7. A transmit unit for supplying current, by way of a telecommunication transmission line, from an electrical direct current power source to an auxiliary load, remote from the direct current power source and to which current is arranged to flow at the end of a second predetermined time interval from the line becoming idle, said transmit unit comprising a first sensing means to sense the state of communication of the line, first switch means to connect, and to disconnect the power source to and from, the line, when the line is idle, and busy, respectively, said connection being made at the end of first predetermined time interval set by a timing means consisting of a first circuit arrangement including a first capacitor, the voltage across which is monitored by a voltage sensitive switch device incorporating a relay which is driven by an emitter follower transistor circuit from a Schmitt trigger arranged to provide a time interval between 40 and 55 seconds, and said disconnection being made when the line is busied.