Telephone pulsing circuit

Claim 2

A telephone pulsing circuit comprising: a pair of input terminals adapted for connection through switching equipment and a telephone line to a telephone set; a pair of power terminals adapted for connection to a direct current power source; a control device responsive to direct current flow therethrough for actuation thereof; circuit means connecting said control device in a direct current series circuit between said input terminals and said power terminals wherein the series circuit, a path through the switching equipment, a telephone line and a telephone set define a direct current telephone loop connection and wherein said control device is actuated when a connected telephone set is off hook, and circuit means, including a timing circuit, coupled to said series circuit for detecting when said telephone loop connection is switched from a closed circuit condition to an open circuit condition, disconnecting said series circuit from said pair of input terminals and simultaneously connecting a direct current circuit across said input terminals, wherein said direct current circuit is applied across the portion of the telephone loop including a path through the switching equipment, a telephone line and a telephone set, for a time duration on the order of the period of the open circuit portion of telephone dial pulses.

Claim 3

A telephone pulsing circuit comprising: a pair of input terminals adapted for connection through switching equipment and a telephone line to a telephone set; a pair of power terminals adapted for connection to a direct current power source; a control device responsive to direct current flow therethrough for actuation thereof; circuit means connecting said control device in a direct current series circuit between said input terminals and said power terminals wherein the series circuit, a path through the switching equipment, a telephone line and a telephone set define a direct current telephone loop connection and wherein said control device is actuated when a connected telephone set is off hook, and circuit means, including a timing circuit, coupled to said series circuit for detecting when said telephone loop connection is switched from a closed circuit condition to an open circuit condition, disconnecting said series circuit from said pair of input terminals and simultaneously connecting a direct current circuit across said input terminals, wherein said direct current circuit is applied across the portion of the telephone loop including a path through the switching equipment, a telephone line and a telephone set, for a time duration on the order of the period of the open circuit portion of telephone dial pulses.

Claim 4

A telephone pulsing circuit comprising: a pair of input terminals adapted for connection through switching equipment and a telephone line to a telephone set; a pair of power terminals adapted for connection to a direct current power source; a control device responsive to direct current flow therethrough for actuation thereof; circuit means connecting said control device in a direct current series circuit between said input terminals and said power terminals wherein the series circuit, a path through the switching equipment, a telephone line and a telephone set define a direct current telephone loop connection and wherein said control device is actuated when a connected telephone set is off hook, and circuit means, including a timing circuit, coupled to said series circuit for detecting when said telephone loop connection is switched from a closed circuit condition to an open circuit condition, disconnecting said series circuit from said pair of input terminals and simultaneously connecting a direct current circuit across said input terminals, wherein said direct current circuit is applied across the portion of the telephone loop including a path through the switching equipment, a telephone line and a telephone set, for a time duration on the order of the period of the open circuit portion of telephone dial pulses.

Claim 5

In a telephone system including an exchange having switching equipment, a pulsing circuit, a plurality of subscriber telephone sets, a telephone line individually connecting each of said telephone sets to the switching equipment so that individual ones of said telephone lines can be selected, and a direct current power source, said pulsing circuit comprising: a pair of conductors for connection to said switching equipment; an inductive control device responsive to be actuated by a direct current flow therethrough; switching means including a plurality of switching circuits, said switching means being responsive to a control signal for rendering said switching circuits conductive and non-conductive; circuit means connecting said control device in a direct current series circuit with a first one of said switching circuits, between said pair of conductors and said power source, wherein said series circuit, a path through the switching equipment and a connected telephone line and set define a direct current telephone loop connection, and wherein said control device is actuated by a closed circuit condition in a connected telephone set; control circuit means coupled to said series circuit and said switching means for detecting when said telephone loop is switched from a closed to an open circuit condition for momentarily applying a control signal to said switching means to momentarily open said first one of said switching circuits, and a direct current discharge circuit connected through a second one of said switching circuits across said pair of conductors so that when said control signal is applied to said switching means said discharge circuit is connected across said pair of conductors and wherein said discharge circuit is applied across the portion of the telephone loop connection including a path through the switching equipment, a telephone line and a telephone set.

Claim 6

In a telephone system including an exchange having switching equipment, a pulsing circuit, a plurality of subscriber telephone sets, a telephone line individually connecting each of said telephone sets to the switching equipment so that individual ones of said telephone lines can be selected, and a direct current power source, said pulsing circuit comprising: a pair of conductors for connection to said switching equipment; an inductive control device responsive to be actuated by a direct current flow therethrough; switching means including a plurality of switching circuits, said switching means being responsive to a control signal for rendering said switching circuits conductive and non-conductive; circuit means connecting said control device in a direct current series circuit with a first one of said switching circuits, between said pair of conductors and said power source, wherein said series circuit, a path through the switching equipment and a connected telephone line and set define a direct current telephone loop connection, and wherein said control device is actuated by a closed circuit condition in a connected telephone set; control circuit means coupled to said series circuit and said switching means for detecting when said telephone loop is switched from a closed to an open circuit condition for momentarily applying a control signal to said switching means to momentarily open said first one of said switching circuits, and a direct current discharge circuit connected through a second one of said switching circuits across said pair of conductors so that when said control signal is applied to said switching means said discharge circuit is connected across said pair of conductors and wherein said discharge circuit is applied across the portion of the telephone loop connection including a path through the switching equipment, a telephone line and a telephone set.

Claim 7

A pulsing circuit as defined in claim 2 wherein: said switching means comprises a relay; said first switching circuit connected in said direct current series circuit comprises normally closed contacts of said relay, and said second switching circuit connecting said discharge circuit to said pair of conductors comprises normally open contacts of said relay.

Claim 8

A pulsing circuit as defined in claim 3 wherein: said control device comprises a relay, and said discharge circuit comprises a direct current circuit including a resistor.

Claim 9

A relay pulsing circuit comPrising; a pair of conductors for connection to a switching circuit that connects and disconnects a direct current circuit across said pair of conductors; a pair of power terminals for connection to a direct current power source; first and second relays each including a coil; circuit means connecting the coil of said first relay in a direct current series circuit with normally closed contacts of said second relay between said power terminals and said pair of conductors; direct current discharge circuit means connected in series with normally open contacts of said second relay across said pair of conductors; capacitive means; rectifying circuit means coupled to a portion of said series circuit including at least said first relay coil, and coupled to said capacitive means, responsive to a signal generated across said first relay coil when said switching circuit switches from a closed to an open circuit load, for applying a charge to said capacitive means, and circuit means connected to said capacitive means and said second relay coil for momentarily energizing said second relay coil in response to said charge on said capacitive means.

Claim 10

A relay pulsing circuit comPrising; a pair of conductors for connection to a switching circuit that connects and disconnects a direct current circuit across said pair of conductors; a pair of power terminals for connection to a direct current power source; first and second relays each including a coil; circuit means connecting the coil of said first relay in a direct current series circuit with normally closed contacts of said second relay between said power terminals and said pair of conductors; direct current discharge circuit means connected in series with normally open contacts of said second relay across said pair of conductors; capacitive means; rectifying circuit means coupled to a portion of said series circuit including at least said first relay coil, and coupled to said capacitive means, responsive to a signal generated across said first relay coil when said switching circuit switches from a closed to an open circuit load, for applying a charge to said capacitive means, and circuit means connected to said capacitive means and said second relay coil for momentarily energizing said second relay coil in response to said charge on said capacitive means.

Claim 11

A relay pulsing circuit as defined in claim 5 including a discharge circuit for said capacitive means for controlling the time duration said second relay is energized.

Claim 12

A relay pulsing circuit as defined in claim 6 including circuit means coupled between a conductor and said capacitive means for discharging said capacitive means when said switching circuit changes from an open circuit load to a closed circuit load.

Claim 13

A relay pulsing circuit as defined in claim 7 wherein said direct current discharge circuit includes a resistive element in series with a diode.

Claim 14

In a telephone system including an exchange having switching equipment, a pulsing circuit, a plurality of subscriber telephone sets, a telephone line individually connecting each telephone set to the switching equipment for selecting individual ones of said telephone sets, and a direct current power source, said pulsing circuit comprising: a pair of conductors for connection to said switching equipment; first and second relays, each of said relays having at least one coil; circuit means connecting at least one coil of said first relay in a direct current series circuit through normally closed circuits of said second relay between said direct current power source and said pair of conductors, wherein the series circuit and the connected telephone line and set define a telephone loop connection, and wherein said first relay is actuated by a closed circuit direct current connection in a connected telephone set; a resistive discharge circuit connected across said pair of conductors through normally open contacts of said second relay; capacitive means; circuit means connected across a portion of said series circuit including at least said one coil of said first relay and connected to said capacitive means for applying a charge to said capacitive means when a connected telephone set is switched from a closed to an open direct current condition; circuit means responsive to the charge across said capacitive means for actuating said second relay, and a discharge circuit for said capacitive means for controlling the time duration said second relay is actuated.

Claim 15

In a telephone system including an exchange having switching equipment, a pulsing circuit, a plurality of subscriber telephone sets, a telephone line individually connecting each telephone set to the switching equipment for selecting individual ones of said telephone sets, and a direct current power source, said pulsing circuit comprising: a pair of conductors for connection to said switching equipment; first and second relays, each of said relays having at least one coil; circuit means connecting at least one coil of said first relay in a direct current series circuit through normally closed circuits of said second relay between said direct current power source and said pair of conductors, wherein the series circuit and the connected telephone line and set define a telephone loop connection, and wherein said first relay is actuated by a closed circuit direct current connection in a connected telephone set; a resistive discharge circuit connected across said pair of conductors through normally open contacts of said second relay; capacitive means; circuit means connected across a portion of said series circuit including at least said one coil of said first relay and connected to said capacitive means for applying a charge to said capacitive means when a connected telephone set is switched from a closed to an open direct current condition; circuit means responsive to the charge across said capacitive means for actuating said second relay, and a discharge circuit for said capacitive means for controlling the time duration said second relay is actuated.

Claim 16

A pulsing circuit as defined in claim 9 wherein the discharge circuit for said capacitive means discharges said capacitive means so that said second relay is energized and subsequently de-energized within a period of time on the order of the open circuit portion of telephone dial pulses.

Claim 17

A pulsing circuit as defined in claim 9 wherein: said circuit means for applying a charge to said capacitive means comprises a rectifying circuit, and including a discharge circuit connected between said capacitive means and one of said pair of conductors providing a second discharge circuit for said capacitive means when second relaY is actuated and a connected telephone set is switched from an open circuit condition to a closed circuit condition.