Abstract:
A skin-contact type terminal system includes a thermoelectric module for cooling or heating in accordance with a polarity of current provided from the skin-contact type terminal, with the temperature of cooling or heating being adjusted according to a level of a voltage provided thereto, and being controlled to maintain its cooling or heating operation for a predetermined time. A control unit senses generation of an alert request signal, supplies the voltage to the thermoelectric module in accordance with the sensed alert request signal so that the thermoelectric module cools or heats in accordance with the predetermined cooling or heating temperature. The control unit controls the thermoelectric module to maintain its cooling or heating operation for the predetermined time.

Description:
CLAIM OF PRIORITY 
     This application makes reference to and claims all benefits accruing under 35 U.S.C. Section 119 from an application entitled, “APPARATUS FOR PROVIDING THERMAL ALERT SIGNAL AND CONTROL METHOD THEREOF IN SKIN-CONTACT TYPE TERMINAL”, filed in the Korean Industrial Property Office on Nov. 11, 1999 and there duly assigned Serial No. 99-49872. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a skin-contact type terminal system. More particularly, the present invention relates to an apparatus for providing a thermal alert signal according to an alert request and a control method thereof in a skin-contact-type terminal. 
     2. Description of the Related Art 
     With the development of modem society, terminals such as portable telephones terminals, various kinds of PDAs, etc., have been become increasingly popular. Some types of terminals, such as the portable telephone terminal, generate a plurality of alert signals including a terminating signal, an alarm signal, etc. 
     As one of such alert signals known in the prior art, a visual alert signal utilizing light is provided. However, this visual alert signal has a problem that it can be confirmed only when the terminal is within the terminal user&#39;s view. 
     Second, a sound alert signal utilizing sound is provided. This sound alert signal has a problem in that it may cause unwanted noise, especially in a public place or a conference room where silence is preferred. 
     Third, in order to solve such a noise problem, a vibration alert signal utilizing vibration is provided. However, this vibration alert signal has problems in that miniaturization of the terminal becomes difficult due to the equipment of a vibrating device for mechanical vibration in the terminal, and the vibration gives the user an unpleasant feeling. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention has been made in an effort to solve the problems occurring in the related art, and an object of the present invention is to provide an apparatus for providing a thermal alert signal and a control method thereof in a skin-contact type terminal system. 
     In order to achieve the above object, according to the present invention, there is provided an apparatus for providing a thermal alert signal in a skin-contact type terminal, comprising: a thermoelectric module for cooling down or heating in accordance with a polarity of current provided thereto, with the cooling or heating temperature adjusted according to a level of a voltage provided thereto, the thermoelectric module being controlled to maintain its cooling or heating operation for a predetermined time; and a control unit for sensing generation of an alert request signal, supplying the voltage to the thermoelectric module in accordance with the sensed alert request signal so that the thermoelectric module cools or heats in accordance with the predetermined cooling or heating temperature, and controlling the thermoelectric module to maintain its cooling or heating operation for the predetermined time. 
     In another aspect of the present invention, there is provided a method of controlling a thermal alert signal providing apparatus in a skin-contact type terminal having a thermoelectric module which generates a thermal alert signal and in which a π-type serial circuit is constructed by connecting in junction each one end of a P-type semiconductor and an N-type semiconductor to an upper metal electrode and by connecting in junction the other end of the P-type semiconductor and the other end of the N-type semiconductor to lower metal electrodes, respectively, an anode is connected to the lower metal electrode connected to the P-type semiconductor, and a cathode is connected to the lower metal electrode connected to the N-type electrode, the method comprising the steps of: setting the thermal alert signal as an alert signal; detecting generation of an alert request in the skin-contact type terminal after the setting of the thermal alert signal as the alert signal; and generating the thermal alert signal as the alert signal if the generation of the alert request is detected. 
     In yet another aspect of the invention, a method for controlling a thermal alert signal includes providing the skin-contact type terminal with heat having a predetermined temperature for contact with a user&#39;s skin to alert the user. 
     The above method may include providing the skin-contact type terminal with cooling having a predetermined temperature for contact with the user&#39;s skin to alert the user. 
     The generating of the thermal alert signal may include one of a heating effect and a cooling effect, wherein the heating effect includes providing heat having a predetermined temperature for contact with a user&#39;s skin to alert the user, and the cooling effect includes providing the skin-contact type terminal with cooling having a predetermined temperature for contact with the user&#39;s skin to alert the user. 
     Finally, if the thermal alert signal is a heating alert signal, the method may include applying a DC voltage to the -type serial circuit so that current flows reversibly from the cathode to the anode, in accordance with the thermal alert signal, so that the heating effect is generated at the upper metal electrode; and if the thermal alert is a cooling alert signal, the method may include applying a DC voltage to the -type serial circuit so that current flows forwardly from the anode to the cathode, in accordance with the thermal alert signal, so that the cooling effect is generated at the upper metal electrode. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above object and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which: 
     FIG. 1 is a perspective view illustrating an example of a skin-contact type terminal for performing the function according to an embodiment of the present invention; 
     FIG. 2 is a perspective view illustrating the rear of the skin-contact type terminal of FIG. 1; 
     FIG. 3 is a block diagram illustrating the internal construction of the skin-contact type terminal for performing the function according to an embodiment of the present invention; 
     FIG. 4 is a block diagram illustrating in detail the internal construction of an alerting unit of FIG. 3; 
     FIG. 5 is a view illustrating the structure of a thermoelectric module of FIG. 4; 
     FIG. 6 is a flowchart illustrating the alert signal setting process according to an embodiment of the present invention; and 
     FIG. 7 is a flowchart illustrating the alert signal generating process according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in greater detail to the preferred embodiments of the present invention with reference to the accompanying drawings. For the purpose of clarity, only the portions for understanding the operation of the present invention are explained and explanation of other portions will be omitted when it may make the subject matter of the present invention rather unclear. 
     FIG. 1 is a perspective view illustrating an example of a skin-contact type terminal for performing the function according to an embodiment of the present invention. 
     FIG. 2 is a perspective view illustrating the rear of the skin-contact type terminal of FIG.  1 . The skin-contact type terminal is secured around the wrist and the rear side is in contact with the user&#39;s wrist. 
     With reference to FIG. 2, a thermoelectric module for generating a thermal alert signal is attached to a proper position  200  of the rear surface of the skin-contact type terminal, so that a user can sense the thermal alert signal. 
     FIG. 3 is a block diagram illustrating the internal construction of the skin-contact type terminal for performing the function according to an embodiment of the present invention. 
     A control unit  111  controls the whole operation of the skin-contact type terminal. A memory  113  stores therein a control program of the skin-contact type terminal and control data produced according to the control operation of the control unit  111 . Especially, in the embodiment of the present invention, the memory  113  also includes an alert signal setting region for storing an alert signal generated in the skin-contact type terminal. The stored alert signal may be a sound alert signal, a vibration alert signal, and a thermal alert signal. 
     A key input unit  115  is provided with a plurality of dialing digit keys, a menu key, a send key, etc., and generates and transfers to the control unit  111  a key signal corresponding to a key selected by a user. 
     An audio memory  117  stores therein a plurality of audio messages. An audio processing unit  119  analog-processes the audio message read out from the audio memory  117  under the control of the control unit  111  to output the analog-processed audio message through a speaker, and digital-processes an analog audio signal inputted through a microphone by the user. 
     A transmitting unit  121  receives a signal generated from the control unit  111 , modulates the input signal to a digital radio signal, and transfers the radio signal to a duplexer  123 . The duplexer  123  transmits the radio signal transferred from the transmitting unit  121  through an antenna, and transfers a radio signal received through the antenna to a receiving unit  125 . The receiving unit  125  demodulates the radio signal transferred from the duplexer  123 , and transfers the demodulated signal to the control unit  111 . The control unit  111  controls a telephone call according to the transferred signal. 
     A display unit  127  comprises by a liquid crystal display (LCD) unit and light-emitting diodes (LEDs), and displays the control data of the telephone terminal and input data under the control of the control unit  111 . 
     An alerting unit  129  is provided with a buzzer, a vibrating motor, a thermoelectric module, etc. If an alert request signal is produced under the control of the control unit  111 , for example, if the alert request signal is produced in response to a call message received from an opposite party for the telephone call, the alerting unit  129  generates a predetermined type alert signal such as a visual alert signal, a sound alert signal, or a thermal alert signal. 
     FIG. 4 is a block diagram illustrating in detail the internal construction of an alerting unit  129  shown in FIG.  3 . 
     With reference to FIG. 4, a buzzer  411  generates the sound alert signal under the control of the control unit  111 , and a vibrating motor  413  generates the vibration alert signal. A thermal alert signal generating unit  420  is composed of a thermoelectric module  421  and a temperature detecting unit  423 , and generates the thermal alert signal under the control of the control unit  111 . Here, the thermoelectric module  421  is implemented by integration of a thermoelectric semiconductor, and generates a heating and cooling alert signal using the Peltier effect of the thermoelectric semiconductor. The temperature detecting unit  423  detects the temperature of the thermal alert signal generated from the thermoelectric module  421  and the ambient temperature. 
     FIG. 5 is a view illustrating the structure of a thermoelectric module  421  shown in FIG.  4 . In particular, the internal construction of the thermoelectric semiconductor is shown in FIG.  5 . 
     With reference to FIG. 5, one end of a P-type semiconductor  503  and one end of an N-type semiconductor  505  are connected in junction to a lower metal electrode  507  and to another lower electrode  508 , respectively, and the other end of the P-type semiconductor  503  and the other end of the N-type semiconductor  505  are connected in junction to an upper metal electrode  509  to construct a -type serial circuit. This -type serial circuit is connected to a DC voltage source  511 , and when current is supplied thereto, holes in the P-type semiconductor  503  are guided to the cathode while electrons in the N-type semiconductor  505  are guided to the anode. At this time, all the holes and electrons take heat from the upper metal electrode  509 , and move to the lower metal electrodes  507  and  508 , respectively, resulting in that the upper metal electrode  509  absorbs heat and the lower metal electrodes  507  and  508  discharge heat. Accordingly, it is possible for the upper metal electrode  509 , which is attached to the proper position  200  of the rear surface of the skin-contact type terminal as shown in FIG. 2, to generate a cooling alert signal. 
     Meanwhile, if the current of the DC voltage source  511  is supplied to the electrodes in an opposite manner to the above-described case, the holes in the P-type semiconductor  503  move to the upper metal electrode  509  by an extracting force from the anode, and the electrons in the N-type semiconductor  505  move to the upper metal electrode  509  by an extracting force from the cathode. At this time, all the holes and electrons take heat from the lower metal electrodes  507  and  508 , and move to the upper metal electrode  509 , resulting in that the upper metal electrode  509  discharges heat and the lower metal electrodes  507  and  508  absorb heat. Accordingly, it is possible for the upper metal electrode  509  to generate a heating alert signal. 
     In the embodiment of the present invention, the current of the voltage source is supplied based on the case that the cooling alert signal is generated. In the case of providing the heating alert signal, the current of the voltage source is supplied in the opposite direction to the case that the cooling alert signal is generated. 
     FIG. 6 is a flowchart illustrating the alert signal setting process according to an embodiment of the present invention. 
     First, at step  611 , if a key signal is inputted from the key input unit  115 , the control unit  111  checks whether or not the input key signal is an alert signal selection mode key signal. At this time, the alert signal selection mode key signal is set by combining a plurality of keys provided in the key input unit  115 . If it is determined at step  611  that the input key signal is not the alert signal selection mode key signal, the control unit  111  then proceeds to step  613 . At step  613 , the control unit  111  performs a function corresponding to the input key signal, and returns to normal operations. 
     If the input key signal is the alert signal selection mode key signal, the control unit  111  then proceeds to step  615 . At step  615 , the control unit  111  converts the present mode of the skin-contact type terminal into an alert signal selection mode, and proceeds to step  617 . At step  617 , the control unit  111  checks whether or not a thermal alert signal selection key signal is inputted from the key input unit  115 . Here, the thermal alert signal selection key signal is set by combining keys provided in the key input unit  115 . If it is determined at step  617  that the input key signal is not the thermal alert signal selection key signal, the control unit then proceeds to step  619 . At step  619 , the control unit  111  performs a function corresponding to the key signal inputted from the key input unit  115 , and returns. Here, as key signals other than the thermal alert signal selection key signal, a vibration alert signal selection key signal and a sound alert signal selection key signal are provided. If the vibration alert signal selection key signal is provided, a corresponding function for setting the vibration alert signal as the alert signal is performed, while if the sound alert signal selection key signal is provided, a corresponding function for setting the sound alert signal as the alert signal is performed. 
     At step  617 , if it is determined that the thermal alert signal selection key signal is inputted, the control unit  111  then proceeds to step  621 . At step  621 , the control unit  111  checks whether or not the key signal inputted from the key input unit  115  is the cooling alert signal selection key signal. If the input key signal is the cooling alert signal selection key s signal, the control unit then proceeds to step  623 . At step  623 , the control unit  111  sets the cooling alert signal as the alert signal in the alert signal setting region of the memory  113 , and proceeds to step  625 . At step  625 , the control unit  111  reads out from the memory  113  a pre-stored cooling temperature setting request message, for instance, a message “Input the cooling temperature.”, displays the message on the display unit  127 , and then proceeds to step  627 . At step  627 , the control unit  111  receives from the key input unit  115  the key signal corresponding to the cooling temperature inputted by the user, and proceeds to step  629 . At step  629 , the control unit  111  sets the cooling temperature in the alert signal setting region, and then proceeds to step  631 . At step  631 , the control unit  111  releases the alert signal selection mode, and returns to normal operation. 
     Meanwhile, if it is determined at step  621  that the key signal inputted from the key input unit  115  is not the cooling alert signal selection key, but is the heating alert signal selection key signal, the control unit  111  then proceeds to step  633 . At step  633 , the control unit  111  sets the heating alert signal as the alert signal in the alert signal setting region of the memory  113 , and then proceeds to step  635 . At step  635 , the control unit  111  reads out from the memory  113  a pre-stored heating temperature setting request message, for instance, a message “Input the heating temperature.”, displays the message on the display unit  127 , and then proceeds to step  637 . At step  637 , the control unit  111  receives from the key input unit  115  the key signal corresponding to the heating temperature inputted by the user, and then proceeds to step  639 . At step  639 , the control unit  111  sets the heating temperature in the alert signal setting region, and proceeds to step  631 . At step  631 , the control unit  111  releases the alert signal selection mode, and returns to normal operation. 
     Also, although not illustrated, it is possible for the user to set the time period where generation of the thermal alert signal, i.e., the cooling alert signal or the heating alert signal, is maintained, and thus the cooling alert signal or the heating alert signal is generated for the time period set by the user. 
     Accordingly, the alert signal setting process of FIG. 6 enables the setting of the cooling alert signal or the heating alert signal as the alert signal. 
     FIG. 7 is a flowchart illustrating the alert signal generating process according to an embodiment of the present invention. 
     With reference to FIG. 7, the control unit  111  checks whether or not the alert request signal is generated at step  711 . Here, the generation of the alert request signal means that a request for generating the alert signal is generated in the case of alerting the user to receipt of a call message according to a call request from an opposite party, arrival of an alarm time, or receipt of a character and audio message. 
     If it is determined at step  711  that the alert request signal is generated, the control unit  111  then proceeds to step  713 . At step  713 , the control unit  111  checks the set alert signal by reading the alert signal setting region of the memory  113 , and then proceeds to step  715 . At step  715 , the control unit  111  checks whether or not the set alert signal is the thermal alert signal. 
     If it is determined that the set alert signal is not the thermal alert signal, the control unit  111  then proceeds to step  717 . At step  717 , the control unit  111  checks whether or not the set alert signal is the sound alert signal. If the set alert signal is determined to be the sound alert: signal, the control unit  111  then proceeds to step  719 . At step  719 , the control unit  111  drives the buzzer  411  to generate the sound alert signal, and returns to normal operation. 
     If it is determined at step  717  that the set alert signal is not the sound alert signal, the control unit  111  then proceeds to step  721 . At step  721 , the control unit  111  drives the vibrating motor  413  to generate the vibration alert signal, and returns. 
     Meanwhile, if it is determined at step  715  that the set alert signal is the thermal alert signal, the control unit  111  then proceeds to step  723 . At step  723 , the control unit  111  checks whether or not the set thermal alert signal is the cooling alert signal. If the set thermal alert signal is determined to be the cooling alert signal, the control unit  111  then proceeds to step  725 . 
     At step  725 , the control unit  111  provides the current of the DC voltage source  511  in a predetermined direction, i.e., as shown in FIG. 5, provides the current to the thermoelectric module by connecting the anode of the DC voltage source  511  to the lower metal electrode  507  connected to the N-type semiconductor  505  and by connecting the cathode of the voltage source  511  to the lower metal electrode  508  connected to the P-type semiconductor  503  so as to generate the cooling alert signal, and returns to normal operation. At this time, by adjusting the level of the voltage applied from the voltage source  511 , it is possible to generate the cooling alert signal with its temperature maintained to be the same as the set cooling temperature. 
     Meanwhile, if it is determined at step  723  that the set thermal alert signal is not the cooling alert signal, the control unit  11  determines the thermal alert signal to be the heating alert signal, and then proceeds to step  727 . At step  727 , the control unit  111  determines the direction of the current to be opposite to that in the case of generating the cooling alert signal, and generates the heating alert signal. Specifically, the control unit  111  provides the current to the thermoelectric module by connecting the cathode of the DC voltage source  511  to the lower metal electrode  507  connected to the N-type semiconductor  505  and by connecting the anode of the voltage source  511  to the lower metal electrode  508  connected to the P-type semiconductor  503  so as to generate the heating alert signal, and returns. At this time, by adjusting the level of the voltage applied from the voltage source  511 , it is possible to generate the heating alert signal with its temperature maintained to be the same as the set heating temperature. 
     As described above, the present invention enables the providing of the thermal alert signal in a skin-contact type terminal. Accordingly, it can solve the problem of the conventional visual alert signal that it can be confirmed only when the terminal is within the terminal user&#39;s view, the problem of the sound alert signal in that it causes a noise especially in a public place or a conference room where silence is required, and the problem of the vibration alert signal in that miniaturization of the terminal becomes difficult due to the equipment of a vibrating device for mechanical vibration in the terminal and the vibration gives the user an unpleasant feeling. 
     While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that other modifications thereof may be made without departing from the scope of the invention. Thus, the invention should not be limited to the disclosed embodiment, but should be defined by the scope of the appended claims and their equivalents.