Automatic hangup apparatus for restoring service to off-hook telephones
First Claim
1. An automatic telephone hangup apparatus for use with a telephone connected to the telephone lines of a telephone system of the type which provides an audible off-hook alert signal which is characterized by containing at least one prearranged identifying frequency to warn the user that his telephone has been left off-hook, wherein the telephone has a voice network and a hookswitch, and wherein the hookswitch is connected between the voice network and the telephone lines so as to connect the voice network to the telephone lines when the hookswitch is closed, and so as to disconnect the voice network from the telephone lines when the hookswitch is open, said automatic telephone hangup apparatus comprising:
- frequency-discriminating off-hook alert signal detecting means for coupling to said telephone lines for detecting signals within a pass band including said identifying frequency and for generating in response thereto an automatic hangup signal;
automatic hangup means for coupling to said telephone and to said alert signal detecting means, for responding to said automatic hangup signal by disconnecting said voice network from said lines.
0 Assignments
0 Petitions
Accused Products
Abstract
The hangup apparatus uses an inadvertent off-hook detector circuit designed to detect the off-hook "howler" alert signal transmitted to a telephone by the telephone company when the telephone has been off-hook for a period of time without any user activity. The detector circuit provides an automatic hangup signal to an automatically actuated hangup switch, disconnecting the telephone voice network from the telephone lines and restoring service to the telephone. One version of the invention can be incorporated into newly manufactured telephones, and another is suitable for use with existing telephones. Both versions can be realized using readily available commercial electronic components.
-
Citations
27 Claims
-
1. An automatic telephone hangup apparatus for use with a telephone connected to the telephone lines of a telephone system of the type which provides an audible off-hook alert signal which is characterized by containing at least one prearranged identifying frequency to warn the user that his telephone has been left off-hook, wherein the telephone has a voice network and a hookswitch, and wherein the hookswitch is connected between the voice network and the telephone lines so as to connect the voice network to the telephone lines when the hookswitch is closed, and so as to disconnect the voice network from the telephone lines when the hookswitch is open, said automatic telephone hangup apparatus comprising:
-
frequency-discriminating off-hook alert signal detecting means for coupling to said telephone lines for detecting signals within a pass band including said identifying frequency and for generating in response thereto an automatic hangup signal; automatic hangup means for coupling to said telephone and to said alert signal detecting means, for responding to said automatic hangup signal by disconnecting said voice network from said lines. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. An inadvertent-off-hook signal apparatus for use with a telephone connected to a telephone system, wherein the telephone has:
- (a) a voice network for transmission and reception of audio signals on the telephone lines of the telephone system;
(b) a hookswitch which connects the voice network to the telephone lines when the hookswitch is in a closed, off-hook position and which disconnects the voice network from the telephone lines when the hookswitch is in an open, on-hook position; and
(c) a signalling device connected across the telephone lines for producing a sensible signal indicative of an incoming telephone call;
said inadvertent-off-hook signal apparatus comprises;inadvertent-off-hook signal detecting means for coupling to said telephone for determination of whether a signal condition indicative of inadvertent off-hook status exists; output signal generator means coupled to said inadvertent-off-hook signal detecting means for responding to said determination of signal condition by producing an output signal having;
(1) a first value when said inadvertent off-hook status does not exist, and (2) a second value different from said first value when said inadvertent off-hook status exists, said output signal accordingly assuming said first or said second value in response to said determination of signal condition; and
,output transducer means coupled to said output signal generator means and having a first sensible response state corresponding to said output signal having said first value, and having a second sensible response state corresponding to said output signal having said second value, said output transducer means responding to said output signal by transiting from said first state to said second state whenever said output signal transits between said first and second values. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
- (a) a voice network for transmission and reception of audio signals on the telephone lines of the telephone system;
-
19. In a telephone apparatus including a telephone adapted for connection to the telephone lines of a telephone system of the type which provides an audible off-hook alert signal which is characterized by containing at least one prearranged identifying frequency to warn the user that his telephone has been left off-hook, wherein the telephone has:
- (a) a voice network for transmission and reception of audio signals on the telephone lines of the telephone system;
(b) a hookswitch connected between the voice network and the telephone lines so as to connect the voice network to the telephone lines when the hookswitch is closed, and so as to disconnect the voice network from the telephone lines when the hookswitch is open; and
(c) a signalling device connected across the telephone lines for producing a sensible signal indicative of an incoming telephone call, the improvement comprising an automatic telephone hangup apparatus coupled to said telephone, said automatic telephone hangup apparatus comprising;frequency-discriminating off-hook alert signal detecting means coupled to said telephone lines for detecting signals within a pass band including said identifying frequency and for generating in response thereto an automatic hangup signal; and
,automatic hangup means, coupled to said telephone and to said alert signal detecting means, for responding to said automatic hangup signal by disconnecting said voice network from said lines. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26, 27)
- (a) a voice network for transmission and reception of audio signals on the telephone lines of the telephone system;
Specification