Sheet carrier device and image forming system for determining whether there is sheet located at tearing jam place when jam occurs

A sheet carrier device comprising:

• a sheet carrying passage including a part configured as a drawable drawer device;
• roller pairs carrying a sheet along the sheet carrying passage;
• a sheet detection device detecting whether there is the sheet which is being carried along the sheet carrying passage;
• and
• a control device including a processor and, by causing the processor to execute a control program, determining whether there is the sheet located in a tearing jam place between the inside and the outside of the drawer device at a time point at which a jam occurs on the basis of a result of detection from the sheet detection device and performing a tearing jam releasing process of removing the sheet from the tearing jam place when it is determined that there is the sheet,
• wherein the control device determines whether there is an upstream sheet suspended between an upstream end in a sheet carrying direction of the drawer device and the outside of the drawer device and whether there is a downstream sheet suspended between a downstream end in the sheet carrying direction of the drawer device and the outside of the drawer device at the time point at which a jam occurs, and
• the sheet carrier device further comprises an upstream roller pair provided upstream in the sheet carrying direction and a downstream roller pair provided downstream in the sheet carrying direction as the roller pairs,
• wherein the control device performs an upstream sheet carrying process of rotationally driving the upstream roller pair to carry the upstream sheet to a staying position at which the upstream sheet is able to stay in the drawer device such that the upstream sheet is not suspended between the inside and the outside of the drawer device as the tearing jam releasing process when a length in the sheet carrying direction of the sheet is equal to or less than a predetermined length which is less than a length in the sheet carrying direction of the drawer device, and
• wherein the control device preforms a total sheet discharging process of rotationally driving the upstream roller pair and the downstream roller pair to discharge all sheets staying in the drawer device from the inside of the drawer device as the tearing jam releasing process when the length in the sheet carrying direction of the sheet is greater than the predetermined length.