Abstract:
A telephone with a mute ringer function having an automatic disabling feature includes multiple call indicators including a ringer. A power output reducing device is connected to the ringer to reduce the ringer volume prior to a connection between the telephone and a remotely located telephone. A volume switch control unit is connected to the power output reducing device to reset the ringer volume to a level established prior to a volume reduction upon detecting either connectivity to the remotely located telephone or the termination of the connection. A selecting device selects an incoming call indicator prior to the connection to the remote telephone. A reverting device automatically reverts power to a previously selected incoming call indicator upon either establishing connectivity for the call or the termination of the call. In a preferred embodiment, the ringer power output reducing device and the ringer power output resetting device include a volume switch connected to the ringer.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates generally to an apparatus and method for muting a telephone ringer, and more specifically to an apparatus and method for selectively muting a telephone ringer prior to a telephone call. 
     DESCRIPTION OF THE RELATED ART 
     Cellular telephones provide a portable means for accessing telecommunications networks. Partially as a consequence of the convenience provided by the portability of cellular telephones, the use of cellular phones has proliferated. However, certain differences between conventional landline telephones and cellular telephones have raised problems previously not encountered in the use of conventional landline telephones. 
     For instance, when a user enters and subsequently transmits a dial string from a cellular telephone, there is a latency period during which the dial string data is received and processed by a central office. Once the central office has processed the dial string data and routed the call, the latency period terminates and a connection is established between the cellular telephone and a remotely located telephone. During the latency period, the cellular telephone can still receive a call from another telephone. A common practice for many users is to place the cellular telephone to an ear after depressing the send key in order to monitor the earpiece for a response from the called party. A problem arises when an incoming call is received during the latency period while a user is monitoring the earpiece. The activation of the ringer by the incoming call causes a potentially painful sensation for the user, because the user&#39;s ear is in such a close proximity to the ringer. The ringer design and volume settings of many cellular phones were not formulated to take into account the possibility that a user might place the ringer so close to the ear of the user contemporaneous to reception of an incoming call. 
     Conventional ringer silencers, such as the one described in U.S. Pat. No. 5,317,632 to Ellison, provide a means for silencing a ringer for a user-determined time period during which a user does not wish to be disturbed by telephone calls. The ringer silencer in this invention is effective for its intended purpose; however, a user is required to manually activate and possibly deactivate the ringer for use in remedying the previously described latency period cellular telephone problem. Consequently, a user might forget to activate the ringer silencer. In addition, the user might set an excessively long time interval for the ringer silencer, thereby unintentionally screening out telephone calls. 
     U.S. Pat. No. 5,191,607 to Meyers et al. describes a communication control console center with a ring tone mute function. When the ring tone mute function is activated and an incoming telephone call is received, the call rings through until either the caller disconnects or a user answers the call. If a second incoming call is then received while the ring tone mute function is activated, the ringer does not sound. The ring tone mute function can be programmed to terminate upon either expiration of a timing sequence or termination of the first telephone call. The Meyers et al. invention provides an effective mute ringer function for screening incoming calls from a second line while a user is taking a call on the first line. However, the invention is not effective for muting the ringer during the above-described latency period prior to a telephonic connection on a cellular telephone. The ring tone mute function only mutes the ringer after a first connection has been established. Consequently, an incoming call during the latency period will not be muted. 
     What is needed is a cellular telephone with a mute ringer capability which prevents a ringer from ringing at full volume during a latency period prior to a connection to a remote telephonic device. 
     SUMMARY OF THE INVENTION 
     A telephone with a mute ringer function having an automatic disabling feature includes at least one incoming call indicator in addition to a ringer. A power output reducing device is connected to the ringer to reduce the ringer volume prior to a connection between the telephone and a remotely located telephone. An automatic reset device is also connected to the ringer to reset the ringer volume to a level established prior to a volume reduction upon detecting either an establishment of the connection to the remotely located telephone or the termination of the connection. A selecting device selects an incoming call indicator prior to the connection to a remote telephone. A reverting device automatically reverts power to a previously selected incoming call indicator upon either the establishment of the connection to the remote telephone or the termination of the connection. 
     In a preferred embodiment, the ringer power output reducing device and the ringer power output resetting device include a volume switch connected to the ringer. A volume switch control unit is configured for transmission of volume reduction signals to the volume switch prior to a connection of the telephone to a remotely located telephonic device and for transmission of volume amplification signals upon termination of the connection. 
     Alternatively, the ringer power output reducing device and the ringer power output resetting device include a call control unit communicatively connected to a call control unit interface with a send key. Depression of the send key automatically triggers transmission of a block incoming call message from the call control unit to a central office. The block incoming call message includes information directing the central office to block incoming calls only until the establishment of the connection to the remotely located telephone. 
     A method for preventing loud ringing of a ringer on a handset of a telephone while the user is operating the telephone includes the steps of selecting one of two mute ringer modes: a reduced ringer volume mode and an alternate incoming call indicator mode. If the reduced ringer volume mode is selected, a power level output of the ringer on the telephone is reduced prior to establishing the connection to the remotely located telephone. The incoming call detector circuitry is maintained in an active state while the connection to the remotely located telephone is established. The connection to the remote telephone is established and the power level of the ringer is automatically increased to a level set prior to the reduction of the ringer power level upon either the establishment of the connection to the remotely located telephone or the termination of the connection. If the alternate incoming call indicator mode is selected, the ringer is disabled. Another incoming call indicator other than the ringer is enabled prior to the establishment of the connection to the remotely located telephone. Upon either the establishment of the connection or the termination of the connection, the ringer is re-enabled and the previously enabled incoming call indicator is disabled. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a cellular telephone having a mute ringer function according to the present invention. 
     FIG. 2 is a perspective view of a landline telephone with two-line capability and having the same mute ringer function as the telephone of FIG. 1. 
     FIG. 3 is a block diagram showing the components of the telephones of FIGS. 1 and 2. 
     FIG. 4 is a flow diagram of a method for executing a mute ringer function of the present invention utilizing the telephone of FIGS. 1 or 2. 
    
    
     DETAILED DESCRIPTION 
     With reference to FIGS. 1 and 2, a cellular telephone 10 and a conventional telephone 11 having two-line capability are connected to a telephone network, such as an analog public switched network, an ISDN line, or a T-1 carrier. The cellular telephone 10 is shown as having an antenna 12 for transmitting voice and signaling information from the cellular telephone 10 to a central office or a relay station. Both the conventional telephone and the cellular telephone are equipped with a speaker 14 for presenting voice information to a user of the telephone. A visual display 16, such as an LCD, displays signaling information, such as caller identification and an outgoing dial string of a called endpoint. Additionally, the LCD 16 displays icons over the softkeys 18 which are indicative of functions, such as a mute ringer function assigned to one of the softkeys. Digit keys 20 are utilized to enter a dial string for transmission to a central office in order to establish a connection to a remote telephone. A send key 19 is provided to enable a user to transmit the dial string to the central office. A ringer, 22 in FIG. 1, not shown in FIG. 2, indicates reception of an incoming call. The ringer of the telephone illustrated in FIG. 2 is located on the handset 26 of the telephone. In either embodiment, the ringer may be either a mechanical or electrical mechanism that generates an audible indication in response to detection of an incoming call. A microphone 24 transmits voice information generated by the user. 
     With reference to FIG. 3, a telephone is equipped with multiple incoming call indicators including a vibrator 36 and a ringer 22. The vibrator is a silent incoming call indicator which notifies the user of an incoming call through its vibrations, while the ringer produces audible ringer sounds to notify the user. Both the ringer 22 and the vibrator 36 are connected to an incoming call signal generator 38 which transmits signals to the vibrator 36 and the ringer 22 upon receipt of an incoming call. A volume switch 42 is located between the incoming call signal generator 38 and the ringer 22 for control of the ringer volume. The volume switch 42 can establish at least two alternative volume levels for the ringer 22. Preferably three different ringer volume levels can be selected; full volume, intermediate volume, and silenced. A volume switch control 50 is connected to the volume switch 42 to set the volume of the ringer 22. An incoming call indicator control 46 communicates with the incoming call signal generator 38 to indicate which of the incoming call indicators to activate upon reception of an incoming call. A call status detector 48 is connected to both the incoming indicator control 46 and the volume switch control 50 to communicate both the establishment of a connection between the telephone 10 and a remote telephone 58 and the termination of the connection. A call control unit 54 transmits and receives call signaling information to and from a central office, not shown, in addition to communicating with the call status detector 48 to provide call status information. 
     A user interface includes softkeys 18, a send key 19, an LCD 16, and a heat sensor 56. The softkeys can be assigned multiple functions, including selection of mute ringer modes. The send key is connected to the call control unit to trigger transmission of a dial string when depressed. Additionally, the send key 19 can be configured to communicate with the incoming call indicator control 46 to trigger selection of the vibrator 36 or to trigger a reduction of ringer volume through communication with the volume switch control 50. 
     Optionally, a heat sensor 56 is embedded on the surface of the earpieces of the telephones 10 and 11 to detect a threshold temperature. Alternatively, the heat sensor could be embedded in a portion of the telephone that contacts the hand of the user. If the threshold temperature is detected, a heat sensor circuit can be programmed to trigger a reduction in ringer volume or to trigger routing of incoming call signals to the vibrator 36 instead of the ringer 22. The softkey 18, the send key 19, and the heat sensor 56 are all connected to the call control unit 54, so that each can trigger transmission of a block incoming call message from the call control unit 54 to the central office. 
     With continued reference to FIGS. 1 through 3, prior to placing a call, the user can utilize one of the softkeys to choose between a reduced ringer volume mode and an alternate incoming call indicator mode. The reduced ringer volume mode reduces the ringer volume so that if a call is received on the cellular telephone 10 during the latency period when the user is monitoring the speaker for a response from a called party, the sounding of the ringer will not discomfort the user as intensely as if the ringer 22 were set at full volume. The reduced ringer volume mode operates in a similar fashion in the conventional telephone 11 with two-line capability when the user is on one line when a call is received on the other line. The ringer reduce volume mode reduces the volume of the ringer in the handset 26 to prevent loud ringing while the handset is placed near the user&#39;s ear. 
     The LCD 16 displays a reduced ringer volume icon over one softkey 18 and an alternate incoming call indicator icon over another softkey 18. Upon initial startup of the operation of the telephones 10 and 11, one of the two mute ringer functions is selected. The user can change the selection at any point. When the user of the cellular telephone 10 places a call, the user enters a dial string utilizing the digit keys 20 and then depresses the send key 19. The send key is dedicated to performing the send function. Alternatively, the send function might be assigned to one of the softkeys. In a preferred embodiment, the send key performs two different functions. Not only does depression of the send key trigger transmission of the dial string to the central office, but it also activates the selected mute ringer mode. The send key is connected to both the incoming call indicator control 46 and the volume switch control 50 to transmit signals activating the selected mute ringer mode. 
     If the reduce ringer volume mode has been selected, depression of the send key 19 triggers transmission of signals to the volume switch control 50. The volume switch control 50 in turn transmits signals to the volume switch 42 positioned between the incoming call signal generator 38 and the ringer 22. The volume switch 42, when activated by the volume switch control 50, causes the ringer 22 to ring at a reduced volume. 
     If the alternate incoming call indicator mode has been selected, depression of the send key 19 triggers transmission of signals to incoming call indicator control 46. The incoming call indicator control 46 transmits routing signals to the incoming call signal generator 38, instructing the incoming call signal generator to activate the vibrator 36 in the event that an incoming call is subsequently received. In this manner, the user automatically activates a previously selected mute ringer mode upon initiating a phone call without having to perform any operations other than those necessary to place the call. Furthermore, the user is still made aware of the incoming call, so that the user can choose to answer or ignore the call. 
     As an alternative to locally muting the ringer 22, the mute ringer function can also be performed at the central office of a telecommunications network in response to signals transmitted from the telephone to the central office. The call control unit 54 transmits a block incoming call message to the central office upon communication from either the send key 19. The block incoming call message contains information instructing the central office not to transmit incoming calls directed to the telephone until the current connection is terminated. 
     Optionally, the cellular telephone 10 and the handset 26 of the conventional telephone 11 have a heat sensor 56 embedded within a portion of the telephone contacted by the user which serves to detect when the user is handling the telephone. When the heat sensors 56 detect that a threshold temperature has been reached, the heat sensors signal either the volume switch control 50 or the incoming call indicator control 46 to activate the preselected mute ringer mode. The threshold temperature should be sufficiently above room temperature to minimize the susceptibility of the sensors to generating false readings. If the user is handling the telephone, it is reasonable to assume that the vibrator and the reduced ringer volume are both sufficient to notify the user of an incoming call. In this manner, the preselected mute ringer mode is activated automatically when the user handles the telephone 10 and 11. 
     The mute ringer function is intended to prevent loud ringing of the ringer 22 prior to establishment of a telephonic connection or during the call. In the cellular telephone embodiment, it is only necessary to mute the ringer during the latent period prior to establishing the connection to the remote telephonic device while the cellular telephone 10 is still capable of receiving telephone calls. Once the connection is established, the cellular telephone 10 can no longer receive incoming calls, and so the mute ringer function is unnecessary. In the conventional two-line telephone embodiment, the telephone 11 is still enabled to receive calls after the telephone 11 has established a connection. Therefore, in the conventional telephone embodiment, the mute ringer function is not disabled until the connection to the remote telephone is disconnected. A call status detector 48 is connected to the call control unit 54 to receive call status information. After the user has activated the preselected mute ringer function in the cellular telephone 10, the call status detector 48 monitors the call control unit 54 to detect the establishment of a connection to a remote telephone. When the connection is established, the call status detector 48 signals to either the incoming call indicator control 46 or the volume switch control 50 depending on which ringer mute mode is selected. If the alternative incoming call indicator mode is selected, then the incoming call indicator control 46 instructs the incoming call signal generator 38 to revert to routing incoming call signals to the ringer 22. If the reduced ringer volume mode is selected, the call status detector 48 signals to the volume switch control 50 to reset the volume switch 42 to the original volume. In the conventional two-line telephone embodiment, the call status detector 48 monitors the call control unit 54 to detect the termination of the connection to the remote telephone 58. Upon termination of the connection, the conventional telephone deactivates the selected mute ringer function in the same manner as the cellular telephone 10. 
     With reference to FIG. 4, a method for muting a telephone ringer 22 includes selecting a mute ringer mode in step 66. A user selects either a reduce ringer volume mode or an alternate incoming call indicator mode, both of which provide an alternative to a full volume ringer mode which can cause substantial discomfort if the ringer is activated while the user has the handset of the telephone to the user&#39;s ear. The user selects the mute ringer mode upon initial activation of the telephone, and the selection can be changed at any time. In step 68, it is determined whether the user selected the reduced ringer volume mode. If the reduced ringer volume mode was selected, then the ringer volume is reduced in step 70. Depression of the send key 19 triggers the volume switch control 50 to set the volume switch 42 at a reduced volume. If any incoming calls are subsequently received, the incoming call signals transmitted from the incoming call signal generator 38 are processed by the volume switch 42 prior to reaching the ringer 22, so that the volume of the ringer is decreased. The incoming call indicator circuitry, which includes the ringer 22 and the incoming call signal generator, is maintained in an active state in step 71 while the user is in the process of establishing a connection to a remote telephonic device. In step 72, a connection to the remote telephonic device is established. The call status detector 48 is utilized to monitor the status of the call in step 72. Upon either the establishment of a connection to a remote telephone or upon the termination of the connection, the call status detector 48 signals to the volume switch control 50. Upon reception of the signal from the call status detector 48, the volume switch control resets the volume switch 42 to the original volume setting in step 74. 
     If in step 68 it is determined that the alternative incoming call indicator mode was selected, the ringer 22 is disabled in step 76. The incoming call indicator control 46 directs the incoming call signal generator 38 to route incoming call signals to the vibrator 36 instead of the ringer 22 in step 78. Any number of other incoming call indicators could be substituted for the vibrator, such as a flashing light. Once the signal generator 38 has been configured to transmit incoming call signals to the vibrator 36, the call status detector 48 monitors the call control unit 54 to detect either connectivity to a remote telephone or the termination of the connection. Upon detecting either the connectivity or the termination, the call status detector 48 signals the incoming call indicator control 46. The incoming call indicator control in turn directs the incoming call signal generator 38 to route incoming call signals to the ringer 22 instead of the vibrator 36 in steps 82 and 84. 
     The above-described invention enables the user of a telephone having a ringer near the ear speaker and which is capable of receiving calls while the user is either awaiting a response from or connected to a called party to mute the ringer to avoid having the ringer disturbingly sound near the ear of the user. Advantageously, the ringer is automatically muted as a connection to a remote telephone is established, and the ringer mute is automatically disabled upon either the establishment of the connection or upon its termination.