Patent ID: 7618037

Claim:
A paper feeding apparatus of an image forming device, comprising: a paper feeding cassette having a side guide part for defining and setting a lateral size of paper, a rear guide part for defining and setting a longitudinal size of paper, and first and second load parts arranged at respective portion of the paper feeding cassette for simultaneously or separately accommodating paper sheets; a first lifting unit arranged to lift the first load part; a second lifting unit arranged to lift the second load part; a paper feeding unit arranged to pick-up and feed the paper sheets loaded on the first load part sheet by sheet, when the first load part is lifted up; and a paper transfer unit arranged to transfer paper sheets loaded on the second load part to the first load part, wherein the first and second lifting units are controlled to lift at least one of the first and second load parts according to determination whether paper sheets are loaded simultaneously on the first and second load parts in a shared manner, wherein the paper transfer unit is controlled to transfer paper sheets on the second load part to the first load part according to determination whether each of the first and second load parts is loaded with paper sheets, wherein the first lifting unit comprises: a first lifter for lifting the first load part up and down between first and second positions; a first position sensor for detecting the first position of the first load part; and a second position sensor for detecting the second position of the first load part, and wherein the first lifter comprises: a first driving motor having a drive shaft; a first lifting plate having a first driving force transfer shaft provided with a first accommodation coupling connected to a first coupling formed at a distal end of the drive shaft of the first driving motor; and a second lifting plate having a second driving force transfer shaft provided with a second gear mated with a first gear formed on the first driving power transfer shaft.