| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an external device capable of suitably cooling a personal digital assistant, and reducing the noise of a fan caused from the personal digital assistant and the external device. <P>SOLUTION: The external device 1 is configured removably from the personal digital assistant 101, which has: a fan 102 for cooling; a control unit 103 for controlling the fan 102 to rotate with a target rotational frequency; and a signal receiving unit 104 for receiving a signal from the outside, and transmitting a signal to the control unit 103. The external device 1 is provided with: a cooling fan 2 for cooling the personal digital assistant 101; and a control unit 3 for detecting the internal temperature of the personal digital assistant 101 while this external device is mounted on the personal digital assistant 101, and transmitting a signal through a signal receiving unit 104 to the control unit 103 of the personal digital assistant 101 in order to make the fan of the personal digital assistant 101 rotate with a rotational frequency which is lower than the target rotational frequency corresponding to the internal temperature, and making the cooling fan 2 rotate with the rotational frequency which is lower than the target rotational frequency. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
