Feeding apparatus, and image forming apparatus incorporating feeding apparatus

A feeding apparatus comprising:

• a feeding roller for conveying a sheet in a sheet feeding direction;
• a separation roller for conveying the sheet in a reverse direction against the sheet feeding direction based on a rotational force transmitted through a torque limiter, the separation roller being opposed to the feeding roller;
• a transmission mechanism for transmitting the rotational force to the feeding roller;
• a limited force reverse transmission mechanism for transmitting the rotational force to the separation roller through the torque limiter;
• a forced reverse transmission mechanism for transmitting the rotational force to the separation roller without passing through the torque limiter;
• a temperature detector for detecting ambient temperature;
• wherein the feeding apparatus is configured to perform a sheet feeding operation, and wherein a start of the sheet feeding operation occurs when the transmission mechanism begins to rotate the feeding roller and the limited force reverse transmission mechanism begins to rotate the separation roller;
• and
• a controller for selecting a sheet separating operation or a sheet detection operation based on detected information from the temperature detector;
• wherein the sheet separating operation is to rotate the feeding roller by applying the transmission mechanism and to rotate the separation roller by applying the forced reverse transmission mechanism for a first predetermined time interval after the limited force reverse transmission mechanism transmits the rotational force to the separation roller, and
• the sheet detection operation is to determine whether a leading edge of the sheet reaches a predetermined place within a second predetermined time interval which is measured from the start of the sheet feeding operation, or from a predetermined time after the start of the sheet feeding operation, and
• wherein if the sheet has reached the predetermined place, the sheet feeding operation is continued, and
• wherein if the sheet has not reached the predetermined place, the rotational force is re-transmitted to the separation roller after the transmission of the rotational force to the separation roller is temporarily stopped, and the separation roller rotates following the feeding roller.