Sequencer for automatic answering and disconnecting device for telephone interfaced facsimile terminals

Claim 2

In a controller for automatically answering the disconnecting calls to and from a cradle switch controlled telephone interfaced with a facsimile unit, said controller including an actuator means for operating said telephone cradle switch and a driver means for moving said actuator means toward and away from said cradle switch to transfer said telephone between an ON HOOK condition and an OFF HOOK condition; a control circuit for sequencing said controller comprising the combination of detector means coupled to said telephone for providing a ring detect signal in response to any ringing voltage applied to said telepone; monitor means coupled to said facsimile unit for providing a message in progress signal in response to facsimile transmission involving said unit; timer means coupled to said detector means and said monitor means for providing a message complete signal upon the expiration of a predetermined time out period, said timer means being activated in response to said ring detect singal and being reset in response to said message in progress signal so that said predetermined time out period runs from the last to occur of said ring detect and message in progress signals; control means coupled to said detector means, monitor means and timer means for conditioning said driver means to move said actuator means away from said telephone cradle switch in response to said ring detect and message in progress signals and toward said telephone cradle switch in response to said message complete signal; and manually resettable inhibitor means activated in response to said message in progress signal for preventing said control means from responding to any subsequent ring detect signal until said inhibitor means is reset.

Claim 3

A control circuit according to claim 1 further including means for overridding said inhibitor means so that a plurality of calls may be automatically answered without any intervention by an operator.

Claim 4

In a controller for automatically answering and disconnecting calls to and from a cradle switch controlled telephone interfaced with a facsimile unit, said controller including an actuator means for operating said telephone cradle switch and a driver means for moving said actuator means toward and away from said cradle switch to transfer said telephone between an ON HOOK condition and an OFF HOOK condition; a control circuit for sequencing said controller comprising the combination of detector means coupled to said telephone for providing a ring detect signal in response to any ringing voltage applied to said telephone; monitor means coupled to said facsimile unit for providing a message in progress signal in response to facsimile transmission involving said unit; timer means coupled to said detector means and said monitor means for providing a message complete signal upon the expiration of a predetermined time out period, said timer means being activated in response to said ring detect signal and being reset in response to said message in progress signal so that said predetermined time out period runs from the last to occur of said ring detect and message in progress signals; control means coupled to said detector means, monitor means and timer means for conditioning said driver means to move said actuator means away from said telephone cradle switch in response to said ring detect and message in progress signals and toward said telephone cradle switch in response to said message complete signal, said control means including bistable means which first switches to a first stable state in response to the first to occur of said ring detect and said message in progress signals and to a second state in response to said message complete signal, said driver means being conditioned to move said actuator away from and toward said cradle switch when said bistable means is in said first and second states, respectively; and manually resettable inhibitor means activated in response to said message in progress signal for preventing said bistable means from switching to said first state in response to any subsequent ring detect signal unless said inhibitor means has previously been reset.

Claim 5

In a controller for automatically answering and disconnecting calls to and from a cradle switch controlled telephone interfaced with a facsimile unit, said controller including an actuator means for operating said telephone cradle switch and a driver means for moving said actuator means toward and away from said cradle switch to transfer said telephone between an ON HOOK condition and an OFF HOOK condition; a control circuit for sequencing said controller comprising the combination of detector means coupled to said telephone for providing a ring detect signal in response to any ringing voltage applied to said telephone; monitor means coupled to said facsimile unit for providing a message in progress signal in response to facsimile transmission involving said unit; timer means coupled to said detector means and said monitor means for providing a message complete signal upon the expiration of a predetermined time out period, said timer means being activated in response to said ring detect signal and being reset in response to said message in progress signal so that said predetermined time out period runs from the last to occur of said ring detect and message in progress signals; control means coupled to said detector means, monitor means and timer means for conditioning said driver means to move said actuator means away from said telephone cradle switch in response to said ring detect and message in progress signals and toward said telephone cradle switch in response to said message complete signal, said control means including bistable means which first switches to a first stable state in response to the first to occur of said ring detect and said message in progress signals and to a second state in response to said message complete signal, said driver means being conditioned to move said actuator away from and toward said cradle switch when said bistable means is in said first and second states, respectively; and manually resettable inhibitor means activated in response to said message in progress signal for preventing said bistable means from switching to said first state in response to any subsequent ring detect signal unless said inhibitor means has previously been reset.

Claim 6

A control circuit according to claim 3 wherein said inhibitor means includes another bistable means which switches from a first stable state to a second stable state in response to said message in progress signal, a manually operable reset switch coupled to said other bistable means to permit said other bistable means to be reset to its first stable state by an operator, and gate means having inputs coupled to said detector means and said second bistable means and an output coupled to the first mentioned bistable means, with said gate means being conditioned to pass said ring detect signal to said first bistable means only when said other bistable means is in its first state.

Claim 7

A control circuit according to claim 4 further including selectively actuatable override means coupled to said gate means, said override means being effective when actuated to override said inhibitor means to thereby condition said gate means to pass any ring detect signals to said first bistable means even when said other bistable means is in its second stable state so that a plurality of calls may be automatically answered without any intervention of an operator if so desired.

Claim 8

A control circuit according to claim 5 further including means coupled between said facsimile unit and said gate means for preventing said inhibitor means from being overriden whenever said facsimile unit is not conditioned for continued operation.

Claim 9

A control circuit according to claim 1 wherein said control means includes a first bistable means coupled to receive said message in progress and message complete signals and gate means coupled to said inhibitor means and to said detector means for passing said ring detect signals to said first bistable means unless inhibitor means is activated, said bistable means being switched to a first stable state to condition said driver means to move said actuator means away from said cradle switch in response to whichever of the ring detect and message in progress signals is first applied to said bistable means and being switched to a second stable state to condition said driver means to move said actuator arm toward said cradle switch in response to said message complete signal.

Claim 10

A control circuit according to claim 1 further including indicator means coupled to said control means and said inhibitor means for providing a first indication when the driver means is conditioned to move the actuator means away from the cradle switch, a second indication when the driver means is conditioned to move the actuator means toward the cradle switch while the inhibitor means is reset, and a third indication when the driver means is conditioned to move the actuator means toward the cradle switch while the inhibitor means is activated.

Claim 11

A control circuit according to claim 2 further including selectively actuatable override means coupled to said gate means and effective when actuated to condition said gate means to pass said ring detect signal even if said inhibitor means is activated.

Claim 12

In a controller for automatically answering and disconnecting calls to and from a cradle switch controlled telephone interfaced with a facsimile unit, said controller including an actuator means for operating said telephone cradle switch and a driver means for moving said actuator means toward and away from said cradle switch to transfer said telephone between an ON HOOK condition and an OFF HOOK condition; a control circuit for sequencing said controller comprising the combination of detector means inductively coupled to said telephone for providing a ring detect signal in response to any ringing voltage applied to said telephone, whereby said detector means responds to any ringing voltage applied to said telephone without requiring any direct electrical connections to said telephone; said detector means including a pick-up coil inductively coupled to said telephone, filter means coupled to said pick-up coil for selectively passing signals induced into said pick-up coil at frequencies with a nominal frequency range for said ringing voltage while suppressing any signals outside said frequency range, and another threshold detector means coupled to said filter means for providing said ring detect signal when the signals passed by said filter means have an average amplitude in excess of a predetermined threshold level; monitor means coupled to said facsimile unit for providing a message in progress signal in response to facsimile transmission involving said unit; timer means coupled to said detector means and said monitor means for providing a message complete signal upon the expiration of a predetermined time out period, said timer means being activated in response to said ring detect signal and being reset in response to said message in progress signal so that said predetermined time out period runs from the last to occur of said ring detect and message in progress signals, said timer means including a capacitive means which is selectively charged and discharged as said timer means is activated and reset, respectively, and a threshold detector means coupled to said capacitive means for providing said message complete signal when said capacitive means charges to a predetermined threshold level, said capacitive means having a charging time constant selected so that the charge thereon reaches said threshold level only after an uninterrupted interval of charging approximately equal in duration to said predetermined time out period, whereby said timer means effectively confirms that any transmission involving said facsimile unit has been completed before providing said message complete signal; control means coupled to said detector means, monitor means and timer means for conditioning said driver means to move said actuator means away from said telephone cradle switch in response to said ring detect and message in progress signals and toward said telephone cradle switch in response to said message complete signal; and means for digitalizing said detect, message in progress and message complete signals; and wherein said control means includes a flip-flop circuit and a coincidence gate, with the flip-flop circuit having respective inputs connected to receive the digitalized ring detect, message in progress and message complete signal and an output connected to one input of said coincidence gate, said coincidence gate having another input connected to receive said digitalized message in progress signal and an output connected to provide a control signal for said driver means; said flip-flop circuit being operated in response to any ring detect or message in progress signal so that said control signal is thereafter held at one logic level to condition its driver means to move said actuator means away from said cradle switch until a message complete signal is provided, whereupon said flip-flop circuit switches to a second stable state, thereby causing said control signal to change to another logic level to condition said driver means to move said actuator means toward said cradle switch.

Claim 13

In a controller for automatically answering and disconnecting calls to and from a cradle switch controlled telephone interfaced with a facsimile unit, said controller including an actuator means for operating said telephone cradle switch and a driver means for moving said actuator means toward and away from said cradle switch to transfer said telephone between an ON HOOK condition and an OFF HOOK condition; a control circuit for sequencing said controller comprising the combination of detector means inductively coupled to said telephone for providing a ring detect signal in response to any ringing voltage applied to said telephone, whereby said detector means responds to any ringing voltage applied to said telephone without requiring any direct electrical connections to said telephone; said detector means including a pick-up coil inductively coupled to said telephone, filter means coupled to said pick-up coil for selectively passing signals induced into said pick-up coil at frequencies with a nominal frequency range for said ringing voltage while suppressing any signals outside said frequency range, and another threshold detector means coupled to said filter means for providing said ring detect signal when the signals passed by said filter means have an average amplitude in excess of a predetermined threshold level; monitor means coupled to said facsimile unit for providing a message in progress signal in response to facsimile transmission involving said unit; timer means coupled to said detector means and said monitor means for providing a message complete signal upon the expiration of a predetermined time out period, said timer means being activated in response to said ring detect signal and being reset in response to said message in progress signal so that said predetermined time out period runs from the last to occur of said ring detect and message in progress signals, said timer means including a capacitive means which is selectively charged and discharged as said timer means is activated and reset, respectively, and a threshold detector means coupled to said capacitive means for providing said message complete signal when said capacitive means charges to a predetermined threshold level, said capacitive means having a charging time constant selected so that the charge thereon reaches said threshold level only after an uninterrupted interval of charging approximately equal in duration to said predetermined time out period, whereby said timer means effectively confirms that any transmission involving said facsimile unit has been completed before providing said message complete signal; control means coupled to said detector means, monitor means and timer means for conditioning said driver means to move said actuator means away from said telephone cradle switch in response to said ring detect and message in progress signals and toward said telephone cradle switch in response to said message complete signal; and means for digitalizing said detect, message in progress and message complete signals; and wherein said control means includes a flip-flop circuit and a coincidence gate, with the flip-flop circuit having respective inputs connected to receive the digitalized ring detect, message in progress and message complete signal and an output connected to one input of said coincidence gate, said coincidence gate having another input connected to receive said digitalized message in progress signal and an output connected to provide a control signal for said driver means; said flip-flop circuit being operated in response to any ring detect or message in progress signal so that said control signal is thereafter held at one logic level to condition its driver means to move said actuator means away from said cradle switch until a message complete signal is provided, whereupon said flip-flop circuit switches to a second stable state, thereby causing said control signal to change to another logic level to condition said driver means to move said actuator means toward said cradle switch.

Claim 14

A control circuit according to claim 10 further including a gate means having one input coupled to said coincidence gate, another input coupled to receive said digitalized message in progress signal, and an output coupled to said timer means, said gate means providing a signal at one logic level to activate said timer means when said control signal is at said one logic level in the absence of a message in progress signal and at another logic level to reset said timer means when said control signal is at said other logic level and when said control signal is at said one logic level in the presence of a message in progress signal.

Claim 15

A control circuit according to claim 11 further including an indicator means coupled to the output of said coincidence gate to provide a first indication when said driver means is conditioned to move said actuator means away from said cradle switch and a second indication when said driver means is conditioned to move said actuator means toward said cradle switch.

Claim 16

A control circuit according to claim 12 further including manually resettable means coupled to receive said digitalized message in progress signal and activated when a message in progress signal is provided subject to being subsequently reset by an operator; and wherein said indicator means is coupled to said manually resettable means and substitutes a third indication for said second indication whenever said manually resettable means is activated while said driver means is conditioned to move said actuator means toward said cradle switch.

Claim 17

A control circuit according to claim 13 wherein said manually resettable means includes inhibitor means coupled to said control means for preventing said control means from responding to any ring detect signals that are provided while said manually resettable means is activated.

Claim 18

A control circuit according to claim 14 wherein said monitor means includes a current transformer inductively coupled to a current supply circuit for said facsimile unit so that a signal having an amplitude proportional to the current being drawn through said supply circuit by said facsimile unit is induced into said transformer, and a further threshold detector means coupled to said transformer for providing said message in progress signal whenever the average amplitude of the signal induced into said current transformer exceeds a predetermined threshold level.

Claim 19

A control circuit according to claim 15 further including modulator means coupled to said supply circuit and responsive to said ring detect message in progress and message complete signals for periodically opening and closing said supply circuit for an interval running from the time a ring detect signal is provided until such time as a message in progress or a message complete signal is provided so that the current applied to said facsimile unit is modulated on and off at a predetermined repitition rate during said interval.