Image forming apparatus

1. An image forming apparatus comprising an apparatus main body having a first surface and a second surface opposed in a first direction, and housing exchangeable components;

a housing body for housing an image reading means that can optically read a document, the housing body disposed on an upper surface side of the apparatus main body, and in which a first end is rotatably connected near the second surface,

the housing body rotatably displacing to a housing body fully closed angle position at which the second end near to the first surface is disposed in closest proximity to the apparatus main body,

a housing body fully open angle position at which the second end is most separated from the apparatus main body, and

a housing body non-access angle position that is between the housing body closed angle and the housing body fully open angle, and that is in proximity to the housing body fully closed angle position;

an outer wall member disposed between the apparatus main body and the housing body, the outer wall member rotatably connected to the apparatus main body, and displacing and rotating in response to the displacement and rotation of the housing body, and

when the housing body is positioned at the housing body fully closed angle position, the outer wall member being positioned at an outer wall fully closed angle position at which the exchangeable components in the inner portion of the apparatus main body are not exposed,

when the housing body is positioned at the housing body fully open angle position, the outer wall member being positioned at an outer wall fully open angle position at which the exchangeable components in the inner portion of the apparatus main body are exposed to enable exchange by a user, and

when the housing body is positioned at the housing body non-access angle position, the outer wall member being positioned at an outer wall non-access angle position that has a rotation angle at which the exchangeable components in the inner portion of the apparatus main body are exposed but cannot be exchanged by a user,

a link member configured to reciprocally displace in the first direction so that

a first end is connected rotatably to the housing body, and

a second end

is positioned at a first position in closest proximity to the first surface when the housing body is positioned at the housing body fully closed angle position,

is positioned at a second position in closest proximity to the second surface when the housing body is positioned at a housing body fully open angle position, and

is positioned at a third position between the first position and the second position in proximity to the first position when the housing body is positioned at a housing body non-access angle position;

a first retaining portion retaining the second end of the link member at the second position, and

a second retaining portion retaining the second end of the link member at the third position.

2. The image forming apparatus according to claim 1 , wherein

when the housing body is disposed at the housing body fully open angle position, the second end of the link member is retained at the second position by the first retaining portion, and the housing body is retained at the housing body fully open angle position, and

when disposed at a position at which the rotation angle is smaller than the housing body fully open angle position, the weight of the housing body displaces the second end of the link member towards the first surface, and the housing body displaces and rotates towards the housing body fully closed angle position and is retained at the housing body non-access angle position since the other end of the retaining link is retained at the third position by the second retaining portion.

3. The image forming apparatus according to claim 2 , wherein the outer wall member

is retained at the outer wall fully open angle position when the housing body is disposed at the housing body fully open angle position, and

when the housing body is disposed at a position at which the rotation angle is smaller than the housing body fully open angle position, the outer wall member displaces and rotates towards the outer wall fully closed angle position, and is retained at the outer wall non-access angle position.

4. The image forming apparatus according to claim 1 , wherein the rotation angle with reference to the outer wall fully closed angle position at the outer wall non-access angle position is from 10° to 20°.

5. The image forming apparatus according to claim 1 , wherein the exchangeable component includes a component connection portion, and

the apparatus main body includes a main body connection portion that projects toward the exchangeable component in response to an closing operation of the housing body, and when the housing body is positioned as a connection angle position that is a predetermined rotation angle with reference to the fully closed angle position, the main body connection portion engages with the component connection portion, and

the rotation angle with reference to the fully closed angle position at the housing body non-access angle position is smaller than the predetermined rotation angle.

6. The image forming apparatus according to claim 1 , wherein the rotation angle with reference to the outer wall fully closed angle position at the outer wall fully open angle position is larger than the rotation angle with reference to the housing body fully closed angle position at the housing body fully open angle position.