Paper sending mechanism with a dynamically adjustable paper-feeding angle

Abstract

A paper sending mechanism with a dynamically adjustable paper-feeding angle has a torsion spring installed at the bottom of a paper tray. The first spring arm of the torsion spring is connected to a printing device, and the second spring arm is attached to the bottom of the paper tray. The torsion spring controls the tilting angle of the paper tray according to the number of papers inside the paper tray. It has the advantage of a low production cost and accurate paper-feeding angle adjustment.

1 . A paper sending mechanism with a dynamically adjustable paper-feeding angle for a printing device, the paper sending mechanism comprising: 
 a paper tray, which accommodates a plurality of pieces of papers, has a paper entrance formed on one side, and extends from the paper tray bottom a suspension arm pivotally connected to the printing device for the paper tray to rotate with respect to the printing device;    a paper-feeding roller, which is installed at the vicinity of the paper entrance of the paper tray;    a paper-separating plate, which is installed at the vicinity of the paper entrance of the paper tray in a movable way to pick, through the paper-feeding roller, a piece of the paper into the printing device; and    a torsion spring, which has a first spring arm and a second spring arm, the second spring arm having an angle with respect to the first spring arm due to an -elastic force; wherein the first spring arm is installed in the printing device and the second spring arm is in contact with the bottom of the paper tray so that when the papers accommodated inside the paper tray get fewer and fewer as being used, the angle between the second spring arm and the first spring arm increases to raise the paper tray by rotating with respect to the suspension arm, thereby increasing the paper-feeding angle of the paper tray with respect to the printing device.    
     
     
         2 . The paper sending mechanism with a dynamically adjustable paper-feeding angle of  claim 1 , wherein the printing device contains an axis for the installation of the torsion spring.  
     
     
         3 . The paper sending mechanism with a dynamically adjustable paper-feeding angle of  claim 1 , wherein the suspension arm contains an axis for the installation of the torsion spring.  
     
     
         4 . The paper sending mechanism with a dynamically adjustable paper-feeding angle of  claim 1 , further comprising an elastic device installed on one side of the paper-separating plate for the paper-separating plate to be regularly in contact with the paper-feeding roller.  
     
     
         5 . The paper sending mechanism with a dynamically adjustable paper-feeding angle of  claim 1 , wherein the paper-feeding roller is covered with a rubber layer.  
     
     
         6 . The paper sending mechanism with a dynamically adjustable paper-feeding angle of  claim 1 , wherein the printing device has a stopper to restrict the first spring arm.