Sheet feeding apparatus

A sheet feeding apparatus, comprising:

• automatic sheet supply means for automatically supplying a sheet in an automatic mode;
• manual sheet insertion means for supplying a manually inserted sheet in a manual mode;
• single detection means capable of detecting the sheet supplied by said automatic sheet supply means and the sheet supplied by said manual sheet insertion means at a first detection position in a sheet supplying path and at a second detection position disposed downstream of said first detection position;
• and
• control means for controlling the supply of the sheet to effect the switching between said automatic mode and said manual mode on the basis of the detection of the sheet at said first detection position and to effect a pre-feed of the sheet on the basis of the detection of the sheet at said second detection position.

An image forming system, comprising:

• automatic sheet supply means for automatically supplying a sheet in an automatic mode;
• manual sheet insertion means for supplying a manually inserted sheet in a manual mode;
• first detection means capable of detecting the sheet supplied by said automatic sheet supply means and the sheet supplied by said manual sheet insertion means;
• second detection means disposed at a downstream side of said first detection means and capable of detecting the sheet;
• control means for controlling the supply of the sheet to effect the switching between said automatic mode and said manual mode on the basis of the detection by said first detection means and to effect the pre-feed of the sheet on the basis of the detection by said second detection means;
• and
• image forming means for forming an image on the pre-fed sheet.

An image forming system, comprising:

• automatic sheet supply means for automatically supplying a sheet in an automatic mode;
• manual sheet insertion means for supplying a manually inserted sheet in a manual mode;
• single detection means capable of detecting the sheet supplied by said automatic sheet supply means and the sheet supplied by said manual sheet insertion means at a first detection position in a sheet supplying path and at a second detection position disposed at a downstream side of said first detection position;
• control means for controlling the supply of the sheet to effect the switching between said automatic mode and said manual mode on the basis of the detection of the sheet at said first detection position and to effect a pre-feed of the sheet on the basis of the detection of the sheet at said second detection position;
• and
• image forming means for forming an image on the pre-fed sheet.

A sheet feeding apparatus comprising:

• automatic sheet supply means for automatically supplying a sheet in an automatic mode;
• manual sheet insertion means for supplying a manually inserted sheet in a manual mode;
• a common path for guiding the sheet supplied by said automatic sheet supply means and the sheet supplied by said manual sheet insertion means;
• detection means for detecting at least three positions of the sheet guided in said common path and outputting a detection signal;
• and
• control means for controlling said automatic sheet supply means and manual sheet insertion means such that the automatic and manual modes are switched in accordance with the detection of the sheet at a first position, the sheet is pre-fed in accordance with the detection of the sheet at a second position and the sheet is in synchronism in operation with an image forming section and in accordance with the detection of the sheet at a third position.

An image forming system comprising:

• automatic sheet supplying means for automatically supplying a sheet in an automatic mode;
• manual sheet insertion means for supplying a manually inserted sheet in a manual mode;
• a common path for guiding the sheet supplied by said automatic sheet supply means and the sheet supplied by said manual sheet insertion means;
• detection means for detecting at least three positions of the sheet guided in said common path and outputting a detection signal;
• control means for controlling said automatic sheet supply means and manual sheet insertion means in such that the automatic and manual modes are switched in accordance with the detection of the sheet of a first position, the sheet is pre-fed in accordance with the detection of the sheet at a second position and the sheet is in synchronism in operation with an image forming section and in accordance with the detection of the sheet at a third position;
• and
• image forming means for forming an image on the pre-fed sheet.