Image forming apparatus having detachable intermediate transfer body

1. An image forming apparatus comprising:

a plurality of image forming units that form toner images having colors being different from each other;

a belt-shaped intermediate transfer body that is arranged on an upper side of the plurality of image forming units in a state that the belt-shaped intermediate transfer body is inclined with respect to a horizontal direction, the toner images formed by the plurality of image forming units being transferred onto the belt-shaped intermediate transfer body;

an intermediate transfer body unit that holds the belt-shaped intermediate transfer body to be freely attached to and detached from an apparatus body; and

a guide rail member that guides the intermediate transfer body unit to be freely attached to and detached from a lateral side of the apparatus body, and that is set so that a direction, in which the intermediate transfer body unit is guided, is changed in the middle of the guiding,

wherein,

the belt-shaped intermediate transfer body that is arranged in a state that the belt-shaped intermediate transfer body is inclined with respect to the horizontal direction so that a downstream side portion of the belt-shaped intermediate transfer body in an attaching direction is raised,

the guide rail member comprises:

a first portion that is arranged in a substantially horizontal direction, or arranged in an inclined direction in which an upstream side portion of the belt-shaped intermediate transfer body in the attaching direction is raised with respect to the horizontal direction;

a second portion that is located on a downstream side of the attaching direction of the belt-shaped intermediate transfer body with respect to the first portion, and is inclined so that the downstream side portion of the belt-shaped intermediate transfer body in the attaching direction is raised with respect to the horizontal direction.

2. The image forming apparatus as claimed in claim 1 , wherein the guide rail member extends from a front side to a rear side of the apparatus body.

3. The image forming apparatus as claimed in claim 1 , wherein the first portion and the second portion of the guide rail member are connected to each other through a bent portion or a curved portion.

4. The image forming apparatus as claimed in claim 1 , wherein the intermediate transfer body unit comprises:

a plurality of power supplies that are arranged substantially in parallel with a direction in which the intermediate transfer body unit is attached to and detached from the apparatus body, and arranged in parallel with an edge of the belt-shaped intermediate transfer body.

5. The image forming apparatus as claimed in claim 1 , wherein the intermediate transfer body unit comprises:

a stopper mechanism that is freely attached to and detached from the apparatus body only in a case where the belt-shaped intermediate transfer body is separate from the plurality of image forming units.

6. The image forming apparatus as claimed in claim 1 , further comprising:

a side cover that is provided on one side of the apparatus body, and is freely opened and closed so as to attach the intermediate transfer body unit to the apparatus body and detach the intermediate transfer body unit from the apparatus body,

wherein

the side cover has an opening angle that is set at least two stages including:

a user operation position at which a jammed sheet of paper is removed; and

a maintenance position at which the opening angle is further increased as compared with the opening angle at the user operation position so that the intermediate transfer body unit is attached to and detached from the apparatus body.

7. The image forming apparatus as claimed in claim 1 , further comprising:

a cleaning device that cleans a surface of the belt-shaped intermediate transfer body, and that is freely inserted into and drawn out from the front side of the apparatus body,

wherein

the cleaning device is freely inserted into and drawn out from the intermediate transfer body unit attached to the apparatus body.

8. The image forming apparatus as claimed in claim 1 , wherein:

the belt-shaped intermediate transfer body comprises:

a first guide pin and a second guide pin that are supported by the guide rail member to guide the belt-shaped intermediate transfer body,

in a state where the first guide pin and the second guide pin are supported by the first portion, the belt-shaped intermediate transfer body is arranged in a substantially horizontal state, or arranged in a state that the upstream side portion of the belt-shaped intermediate transfer body in the attaching direction is raised with respect to the horizontal direction,

in a state where the first guide pin and the second guide pin are supported by the second portion, the belt-shaped intermediate transfer body is arranged in a state that the downstream side portion of the belt-shaped intermediate transfer body in the attaching direction is raised with respect to the horizontal direction, and

an inclination angle of the belt-shaped intermediate transfer body varies at stages which has a stage where the first guide and the second guide pin are supported by the first portion, a stage where the first guide pin is supported by the first portion and the second guide pin is supported by the second portion, and a stage where the first guide pin and the second guide pin are supported by the second portion, in that order.