Sheet feeding apparatus and image forming apparatus

A sheet feeding apparatus comprising:

• a conveying roller;
• a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side;
• a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion;
• a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller;
• and
• a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance,
• wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the conveying roller and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface.

A sheet feeding apparatus comprising:

• a conveying roller;
• a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side;
• a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion;
• a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller;
• and
• a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance,
• wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the separation member and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface.

An image forming apparatus comprising a sheet feeding apparatus,

• the sheet feeding apparatus comprising
• a conveying roller;
• a separation member which presses against the conveying roller to form a separation nip portion that separates received sheets one by one,
• a nip guide member having a sloped guide surface whose guide leading-end receives a force toward the conveying roller in a position distant from the conveying roller with a predetermined distance to slope so as to guide a leading end of a sheet to the separation nip portion, and
• a support member which supports the nip guide member not to recede from the conveying roller when a thickness of a sheet bundle bumping into the sloped guide surface is smaller than the predetermined distance between the conveying roller and the guide leading-end and supports the nip guide member to recede from the conveying roller when the thickness is larger than the predetermined distance, and
• an image forming portion, in which an image is formed on a sheet fed from the sheet feeding apparatus.

An image forming apparatus comprising a sheet feeding apparatus,

• the sheet feeding apparatus having
• a conveying roller,
• a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side,
• a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion,
• a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller;
• and
• a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance,
• wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the conveying roller and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface, and
• an image forming portion, in which an image is formed on a sheet fed from the sheet feeding apparatus.

An image forming apparatus comprising a sheet feeding apparatus,

• the sheet feeding apparatus having
• a conveying roller,
• a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side,
• a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion,
• a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller, and
• a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance,
• wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the separation member and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface.