Sheet feeding device

A sheet feeding device comprising:

• a stacking portion on which a plurality of recording materials are stacked;
• a feeding rotary member configured to feed the plurality of recording materials stacked on the stacking portion one by one, wherein the feeding rotary member feeds a first recording material which is an uppermost recording material stacked on the stacking portion and a second recording material positioned under the first recording material;
• a conveying rotary member configured to convey the recording material fed by the feeding rotary member;
• a separating rotary member configured to form a nip with the conveying rotary member, wherein the separating rotary member is rotated in a predetermined direction so as to convey the first recording material when the first recording material is fed to the nip, and the separating rotary member stops in rotation or rotates in a direction opposite to the predetermined direction so as to separate the first recording material and the second recording material when the first recording material and the second recording material are fed to the nip;
• a detecting unit provided upstream of the nip with respect to a recording material feeding direction and configured to detect a feeding speed of the recording material;
• a driving unit configured to execute a feeding operation by the feeding rotary member;
• and
• a threshold determining unit configured to determine a threshold speed depending on the feeding speed of the recording material detected by the detecting unit in a period in which the separating rotary member is rotated in the predetermined direction in a state where the first recording material is fed to the nip after the feeding operation of the first recording material is started;
• a feeding control unit configured to control the driving unit to execute the feeding operation of the second recording material subsequently to passing of a trailing end of the first recording material through the feeding rotary member in an overlapping state where the first recording material and the second recording material partially overlap,
• wherein, in a case where the feeding speed detected by the detecting unit is faster than the threshold speed, the feeding control unit controls the driving unit to continue the feeding operation of the second recording material,
• wherein, in a case where the feeding speed detected by the detecting unit becomes slower than the threshold speed while the separating rotary member is rotated in the predetermined direction, the feeding control unit controls the driving unit to stop the feeding operation of the second recording material in a state where a leading end of the second recording material reaches the nip,
• wherein the sheet feeding device further comprises a second detecting unit, provided downstream of the nip with respect to a recording material feeding direction, the second detecting unit being configured to detect a leading end of the recording material, and
• wherein the threshold determining unit determines the threshold speed according to the rotational speed of the separating rotary member in a period from when the second detecting unit detects a leading end of the first recording material to when a distance between the trailing end of the first recording material and the feeding rotary member with respect to the feeding direction becomes a predetermined distance.

A sheet feeding device comprising:

• a stacking portion on which a plurality of recording materials are stacked;
• a feeding rotary member configured to feed the plurality of recording materials stacked on the stacking portion one by one, wherein the feeding rotary member feeds a first recording material which is an uppermost recording material stacked on the stacking portion and a second recording material positioned under the first recording material;
• a conveying rotary member configured to convey the recording material fed by the feeding rotary member;
• a separating rotary member configured to form a nip with the conveying rotary member, wherein the separating rotary member is rotated in a predetermined direction so as to convey the first recording material when the first recording material is fed to the nip, and the separating rotary member stops in rotation or rotates in a direction opposite to the predetermined direction so as to separate the first recording material and the second recording material when the first recording material and the second recording material are fed to the nip;
• a detecting unit configured to detect a rotational speed of the separating rotary member;
• a driving unit configured to execute a feeding operation by the feeding rotary member;
• and
• a feeding control unit configured to control the driving unit to execute the feeding operation of the second recording material subsequently to passing of a trailing end of the first recording material through the feeding rotary member in an overlapping state where the first recording material and the second recording material partially overlap,
• wherein, in a case where the rotational speed of the separating rotary member detected by the detecting unit does not continuously decrease a number of times exceeding a threshold number of times, the feeding control unit controls the driving unit to continue the feeding operation of the second recording material, and
• wherein, in a case where the rotational speed of the separating rotary member continuously decreases a number of times exceeding the threshold number of times, the feeding control unit controls the driving unit to stop the feeding operation of the second recording material in a state where a leading end of the second recording material reaches the nip.