Patent ID: 8157762

Claim:
A portable medical liquid infusion device for quantitatively measuring medical liquid infusion rate, and notifying the medical liquid infusion rate by a droplet drop period, the infusion device comprising: a key input unit ( 120 ) which receives a selection of an infusion rate control mode or an infusion rate measuring mode, receives an input of the quantity of medical liquid infused per unit time, receives a count input from a user each time when a droplet ( 23 ) drops downward in a drip chamber ( 22 ), and receives a selection of a droplet volume according to the use of the medical liquid; a display unit ( 130 ) which outputs the quantity of the medical liquid and a length of infusion time input by the user at the infusion rate control mode so that the user can confirm the quantity of the medical liquid and the length of infusion time, and quantitatively outputs the supply rate of the medical liquid calculated at the infusion rate measuring mode; a speaker ( 140 ) which outputs acoustic waves of a predetermined period at the infusion rate control mode; an oscillating unit ( 150 ) for oscillating electric signals of a predetermined frequency; a power supply unit ( 160 ) for supplying power; and a control unit ( 110 ), wherein at the infusion rate control mode, the control unit ( 110 ) determines the drop period of droplets by dividing the quantity of the medical liquid infused per unit time, which is input through the key input unit ( 120 ), by the droplet volume selected through the key input unit ( 120 ), and outputs acoustic waves corresponding to the drop period of droplets to the speaker ( 140 ) using the electric signal frequency of the oscillating unit ( 150 ), and at the infusion rate measuring mode, the control unit ( 110 ) calculates the length of time consumed for receiving count inputs by the preset number of times after the droplet volume is selected, on the basis of the electric signal frequency of the oscillating unit ( 150 ), converts the preset number of times into the number of droplets per unit time by substituting the calculated length of time, determines the quantitative medical liquid infusion rate by multiplying the preset droplet volume and the converted number of droplets per unit time, and outputs the determined infusion rate to the display unit ( 130 ), and wherein at the infusion rate measuring mode, the control unit ( 110 ) calculates a mean value for the count input time intervals of the previous step, and calculates the ratio of the current count input time interval in relation to the calculated mean value, and if the calculated ratio is out of a preset range, the control unit determines the infusion rate by calculating the length of time consumed for count inputs of the preset number of times to be received thereafter.