Sheet feeding device and image forming apparatus incorporating the same

Abstract

A sheet feeding device includes a body, a sheet tray including a contacted portion, a conveyance roller pair, and a contact-separation mechanism. The conveyance roller pair in the body includes one roller and another roller. The contact-separation mechanism includes a spring and a movable part. The movable part pushed by the spring in a first direction has a contact portion and an elongated guide. The contact portion contacts the contacted portion in response to an insertion of the sheet tray into the body to move the movable part in a second direction opposite to the first direction. The elongated guide changes a position of said another roller in a third direction orthogonal to the first and second directions with respect to the one roller according to a movement of the movable part in the first direction and second direction.

1 . A sheet feeding device comprising:
 a body;   a sheet tray insertable to and removable from the body to store a sheet, the sheet tray including a contacted portion;   a conveyance roller pair in the body to convey the sheet stored in the sheet tray to a conveyance passage in the body, the conveyance roller pair including one roller and another roller; and   a contact-separation mechanism to contact or separate said another roller to and from the one roller, the contact-separation mechanism including:
 a spring; and 
 a movable part pushed in a first direction by the spring, the movable part having:
 a contact portion contactable with the contacted portion of the sheet tray in response to an insertion of the sheet tray into the body to move the movable part in a second direction opposite to the first direction against the spring; and 
 an elongated guide to change a position of said another roller in a third direction orthogonal to the first direction and the second direction with respect to the one roller according to a movement of the movable part in the first direction or the second direction. 
 
   
     
     
         2 . The sheet feeding device according to  claim 1 , further comprising
 a holder holding said another roller and including a fitting portion fitting to the elongated guide,   wherein the elongated guide having:
 a first opening having a rectangular shape extending in the first direction; 
 a second opening shifted from the first opening in the third direction farther from the one roller than the first opening, the second opening having a rectangular shape extending in the first direction; and 
 a third opening connecting the first opening and the second opening and inclined with respect to the first opening and the second opening. 
   
     
     
         3 . The sheet feeding device according to  claim 2 ,
 wherein the first opening is downstream from the second opening in the first direction,   the elongated guide further has a fourth opening having a rectangular shape extending in the first direction,   the fourth opening is downstream from the first opening in the first direction, and   the fourth opening is closer to the one roller than the first opening in the third direction.   
     
     
         4 . The sheet feeding device according to  claim 2 ,
 wherein the elongated guide includes a stopper in the first opening to restrict movement of the fitting portion in the first direction.   
     
     
         5 . The sheet feeding device according to  claim 1 , further comprising:
 another contact-separation mechanism disposed at one end of the sheet feeding device in an axial direction of said another roller; and   another contacted portion of the sheet tray disposed at one end of the sheet tray in the axial direction,   wherein the contact-separation mechanism is disposed at another end of the sheet feeding device in the axial direction, and   the contacted portion of the sheet tray is disposed at another end of the sheet tray in the axial direction.   
     
     
         6 . The sheet feeding device according to  claim 1 ,
 wherein the contact portion has a first inclined face inclined with respect to an insertion and removement direction of the sheet tray,   the contacted portion has a second inclined face contactable with the first inclined face of the contact portion, and   the second inclined face is inclined with respect to the insertion and removement direction of the sheet tray.   
     
     
         7 . The sheet feeding device according to  claim 1 ,
 wherein the contacted portion includes a roller contacting the contact portion.   
     
     
         8 . The sheet feeding device according to  claim 1 , further comprising
 a driver to rotate the one roller,   wherein said another roller is rotated by a rotation of the one roller.   
     
     
         9 . An image forming apparatus comprising the sheet feeding device according to  claim 1 . 
     
     
         10 . The image forming apparatus according to  claim 9 , further comprising:
 wherein the conveyance roller pair conveys the sheet in the sheet tray to the conveyance passage in the body in a conveyance direction,   an insertion and removement direction of the sheet tray is in the conveyance direction, and   the conveyance roller pair is downstream from the sheet tray in the conveyance direction.