Patent ID: 9597903
Date: 2017-03-21
CPC Classifications: B41J

Claim:
1. A printer configured for accommodating a paper roll formed by rolling a paper sheet, the printer comprising: a main body having an accommodating space and a shaft, the accommodating space configured for accommodating the paper roll, the shaft located in the accommodating space and configured for installation of the paper roll; a cover pivoted to the main body for covering the accommodating space or leaving the accommodating space exposed; a first printing set disposed in the main body; a second printing set disposed on the cover, a paper channel defined between the first printing set and the second printing set when the cover covers the accommodating space, the paper channel having a paper inlet and a paper outlet which are opposite to each other, and the paper inlet connected to the accommodating space; and a detecting module, comprising: wherein the paper channel is configured for the paper sheet to pass through, when the paper roll is full, a first paper feeding angle of the paper roll is θ1, when the paper roll is used up, a second paper feeding angle of the paper roll is θ2, and the following condition is satisfied: θ1>θ2; wherein a vertical distance between the movable section and the paper inlet of the paper channel is D, there is a first detecting area having two first sides which are opposite to each other, each of the two first sides of the first detecting area is parallel to a reference line which is simultaneously passing through the paper inlet of the paper channel and a shaft axis of the shaft, a distance from the reference line to each of the two first sides is equal to D×tan θ1, when the movable section of the flexible member is not pressed by the paper sheet, the movable section is located in the first detecting area.