Image forming apparatus

1. An image forming apparatus comprising:

an image carrier on which a plurality of toner images is formed, each of the toner images corresponding to a different color;

a developing unit that develops an electrostatic latent image formed on the image carrier to sequentially form the toner images on the image carrier;

a transferring unit that transfers the toner image formed on the image carrier to a sheet at a transfer position;

a fixing unit that fixes the toner image transferred to the sheet at a fixing position;

a conveying unit that conveys the sheet along a conveying path that circulates around the image carrier, to repeatedly transfer and fix the plurality of toner images to the sheet, each of the toner images being sequentially transferred and fixed to the sheet one at a time;

a sheet shape detecting unit that detects information indicative of a shape of the sheet that is conveyed through the conveying path;

a discharge position where the sheet is discharged from the conveying path, a feed position where the sheet is fed to the conveying path and a detection position where the information indicative of the shape of the sheet is detected by the sheet shape detecting unit are arranged in this sequence along a sheet conveying direction to be close to one another, immediately downstream in the sheet conveying direction from the fixing position where the toner image is fixed to the sheet,

a distance from the feed position along the conveying path in the sheet conveying direction to the discharge position is greater than a distance from the discharge position along the conveying path in the sheet conveying direction to the feed position, and a distance from the feed position along the conveying path in the sheet conveying direction to the transfer position, where each of the toner images is sequentially transferred to the sheet one at a time, is greater than a distance from the transfer position along the conveying path in the sheet conveying direction to the feed position,

wherein the discharge position, the feed position and the detection position are on a same side with respect to a first plane which is perpendicular to a second plane connecting the transfer position of the transferring unit to the fixing position of the fixing unit and which passes through the transfer position, the second plane connecting the transfer position of the transferring unit to the fixing position of the fixing unit being substantially vertical, and

wherein a length of a conveying path extending from the detection position to the transfer position in the conveying direction is equal to or greater than the maximum sheet length for the image forming apparatus.

2. The image forming apparatus according to claim 1 , further comprising:

a feed sheet housing portion for housing the sheet prior to conveyance along the conveying path; and

a discharge sheet housing portion for housing the sheet after discharge from the conveying path,

wherein the feed sheet housing portion and the discharge sheet housing portion are placed so that a first path portion of the conveying path, the first path portion extending from the transfer position to the fixing position, a sheet which is housed in the feed sheet housing portion, and a sheet which is housed in the discharge sheet housing portion are opposed to one another.

3. The image forming apparatus according to claim 2 , wherein

the feed sheet housing portion is placed to be opposed to the first path portion across a second path portion of the conveying path, the second path portion extending from the fixing position to the transfer position, and

the discharge sheet housing portion is placed to be opposed to the first path portion across the second path portion and the feed sheet housing portion.

4. An image forming apparatus comprising:

an image carrier on which a plurality of toner images is formed, each of the toner images corresponding to a different color;

a developing unit that develops an electrostatic latent image formed on the image carrier to sequentially form the toner images on the image carrier;

a transferring unit that transfers the toner image formed on the image carrier to a sheet at a transfer position;

a fixing unit that fixes the toner image transferred to the sheet at a fixing position;

a conveying unit that conveys the sheet along a conveying path that circulates around the image carrier, to repeatedly transfer and fix the plurality of toner images to the sheet, each of the toner images being sequentially transferred and fixed to the sheet one at a time;

a sheet shape detecting unit that detects information indicative of a shape of the sheet that is conveyed through the conveying path;

a discharge position where the sheet is discharged from the conveying path, a feed position where the sheet is fed to the conveying path and a detection position where the information indicative of the shape of the sheet is detected by the sheet shape detecting unit are arranged in this sequence along a sheet conveying direction to be close to one another, immediately downstream in the sheet conveying direction from the fixing position where the toner image is fixed to the sheet,

wherein the discharge position, the feed position and the detection position are on a same side with respect to a first plane which is perpendicular to a second plane connecting the transfer position of the transferring unit to the fixing position of the fixing unit and which passes through the transfer position, the second plane connecting the transfer position of the transferring unit to the fixing position of the fixing unit being substantially vertical, and

wherein a length of a conveying path extending from the detection position to the transfer position in the conveying direction is equal to or greater than the maximum sheet length for the image forming apparatus.