Controlling method for thermoelectric cooling device and heat-dissipating module employing same

Abstract

A controlling method for a thermoelectric cooling device is provided. The thermoelectric cooling device has a cold side and a hot side. After the thermoelectric cooling device is enabled, a temperature of the cold side and an ambient temperature around the thermoelectric cooling device are acquired. By judging whether the ambient temperature is higher than or equal to a preset reference temperature, an initial value of a duty cycle corresponding to an electric energy to be received by the thermoelectric cooling device is set. Then, a judging step is performed to judge whether the temperature of the cold side is higher than or equal to the ambient temperature. If the judging condition is satisfied, the duty cycle is increased by a specified percentage. If the judging condition is not satisfied and the duty cycle is higher than 0%, the duty cycle is decreased by the specified percentage.

What is claimed is:  
     
         1 . A controlling method for a thermoelectric cooling device, the thermoelectric cooling device having a cold side and a hot side, the method comprising steps of:
 (a) enabling the thermoelectric cooling device, and acquiring a temperature of the cold side and an ambient temperature around the thermoelectric cooling device;   (b) judging whether the ambient temperature is higher than or equal to a preset reference temperature;   (c) setting an initial value of a duty cycle corresponding to an electric energy to be received by the thermoelectric cooling device according to a judging result of the step (b);   (d) judging whether the temperature of the cold side is higher than or equal to the ambient temperature;   (e) if the judging condition of the step (d) is satisfied, increasing the duty cycle by a specified percentage, and repeatedly performing the step (d); and   (f) if the judging condition of the step (d) is not satisfied, decreasing the duty cycle by the specified percentage and repeatedly performing the step (d) by judging whether the duty cycle is higher than 0%.   
     
     
         2 . The controlling method according to  claim 1 , wherein in the step (c), if the ambient temperature is higher than or equal to the preset reference temperature, the initial value of the duty cycle is set as 50%. 
     
     
         3 . The controlling method according to  claim 1 , wherein in the step (c), if the ambient temperature is higher than or equal to the preset reference temperature, the initial value of the duty cycle is set as 50% after a delaying time. 
     
     
         4 . The controlling method according to  claim 1 , wherein in the step (c), if the ambient temperature is lower than the preset reference temperature, the initial value of the duty cycle is set as 0%. 
     
     
         5 . The controlling method according to  claim 1 , wherein in the step (b), the preset reference temperature is 30° C. 
     
     
         6 . The controlling method according to  claim 1 , wherein in the step (f), if the duty cycle is higher than 0%, the duty cycle is decreased by the specified percentage, and the step (d) is repeatedly done. 
     
     
         7 . The controlling method according to  claim 1 , wherein in the step (f), if the duty cycle is equal to 0%, the step (d) is repeatedly done. 
     
     
         8 . A heat-dissipating module, comprising:
 a thermoelectric cooling device having a cold side and a hot side;   a power supply circuit electrically connected with the thermoelectric cooling device and operated at a duty cycle for providing electric energy to the thermoelectric cooling device and driving the thermoelectric cooling device;   a first temperature sensor disposed adjacent to the cold side of the thermoelectric cooling device for detecting a temperature of the cold side;   a second temperature sensor for detecting an ambient temperature around the thermoelectric cooling device; and   a controller electrically connected with the first temperature sensor, the second temperature sensor and the power supply circuit, judging whether the temperature of the cold side of the thermoelectric cooling device is higher than or equal to the ambient temperature according to a detecting result of the first temperature sensor and the second temperature sensor, and adjusting the duty cycle of the power supply circuit according to a judging result for adjusting the electric energy provided by the power supply circuit correspondingly.   
     
     
         9 . The heat-dissipating module according to  claim 8 , wherein the controller performs a controlling method comprising steps of:
 (a) enabling the thermoelectric cooling device, and acquiring the temperature of the cold side and the ambient temperature around the thermoelectric cooling device;   (b) judging whether the ambient temperature is higher than or equal to a preset reference temperature;   (c) setting an initial value of the duty cycle corresponding to an electric energy to be received by the thermoelectric cooling device according to a judging result of the step (b);   (d) judging whether the temperature of the cold side is higher than or equal to the ambient temperature;   (e) if the judging condition of the step (d) is satisfied, increasing the duty cycle by a specified percentage, and repeatedly performing the step (d); and   (f) if the judging condition of the step (d) is not satisfied, decreasing the duty cycle by the specified percentage and repeatedly performing the step (d) by judging whether the duty cycle is higher than 0%.   
     
     
         10 . The heat-dissipating module according to  claim 8 , wherein the first temperature sensor is in direct contact with the cold side of the thermoelectric cooling device. 
     
     
         11 . The heat-dissipating module according to  claim 8 , further comprising a plurality of fins disposed on the hot side of the thermoelectric cooling device for transferring the heat of the hot side. 
     
     
         12 . The heat-dissipating module according to  claim 8 , further comprising a third temperature sensor located near the hot side of the thermoelectric cooling device and electrically connected with the controller for detecting the temperature of the hot side, wherein when the temperature of the hot side of the thermoelectric cooling device exceeds a protective temperature, the controller controls the power supply circuit to stop providing electric energy to the thermoelectric cooling device.