Web conveying device, image forming apparatus, and conveying roller capable of efficiently sucking air that enters between web and conveying roller

A conveying roller comprising:

• a roller portion configured to rotate in contact with a web;
• a first air passage extending, in an axial direction of a rotation shaft of the roller portion, inside an outer peripheral portion of the roller portion and communicating with an outside at an end on a side of a first direction parallel to the axial direction;
• and
• a plurality of second air passages extending from the first air passage in a direction that forms an obtuse angle with respect to the first direction and communicating with the outside of the outer peripheral portion, wherein
• the second air passages are arranged along the axial direction,
• the second air passages are arranged along the outer peripheral portion,
• the first air passage includes a closed end and an open end, wherein the closed end is located at an upstream side of the first direction and is blocked from the outside, and the open end is located at a downstream side of the first direction, and is open to the outside, and
• each of the plurality of second air passages arranged along the axial direction is formed such that the closer an arrangement position is to the closed end of the first air passage on the upstream side in the first direction, the larger a cross-sectional area of each of the plurality of second air passages.

A conveying roller comprising:

• a roller portion configured to rotate in contact with a web;
• a first air passage extending, in an axial direction of a rotation shaft of the roller portion, inside an outer peripheral portion of the roller portion and communicating with an outside at an end on a side of a first direction parallel to the axial direction;
• and
• a plurality of second air passages extending from the first air passage in an outward extension direction that forms an obtuse angle with respect to the first direction and communicating with the outside of the outer peripheral portion, wherein
• the second air passages are arranged along the axial direction,
• the second air passages are arranged along the outer peripheral portion,
• the first air passage includes a closed end and an open end, wherein the closed end is located at an upstream side of the first direction and is blocked from the outside, and the open end is located at a downstream side of the first direction, and is open to the outside, and
• each of the plurality of second air passages arranged along the axial direction is formed such that the closer an arrangement position is to the closed end of the first air passage on the upstream side in the first direction, the larger the obtuse angle formed between the outward extension direction of each of the plurality of second air passages and the first direction of the first air passage.