Medium transporting device, image reading apparatus, and opening/closing device

1. A medium transporting device comprising:

a main body portion that constitutes a medium transporting path through which a medium is transported;

an opening/closing body that is provided to be rotatable with respect to the main body portion, forms the medium transporting path between the opening/closing body and the main body portion by closing thereof, and exposes the medium transporting path by opening thereof; and

a holding unit that holds the opening/closing body in a state where the opening/closing body is open,

wherein the holding unit includes:

a rotation member that has a supporting portion which is capable of being displaced between a state of being raised up and a state of being dropped down by rotation thereof and supports the opening/closing body and applies a force to the opening/closing body in an opening direction by the supporting portion engaging with the opening/closing body, and

a pressing unit that presses the rotation member in the raised direction, and

wherein the holding unit further includes a configuration in which a force that the supporting portion applies to the opening/closing body in the opening direction due to a pressing force to the rotation member generated by the pressing unit and a force that the opening/closing body tries to close are balanced with each other according to a predetermined rotation angle of the rotation member,

wherein the supporting portion of the rotation member is capable of engaging with and disengaging from the opening/closing body and disengages from the opening/closing body by the rotation angle of the rotation member reaching the upper limit when the opening/closing body exceeds a predetermined opening angle.

2. The medium transporting device according to claim 1 ,

wherein the pressing unit does not apply an external force in the raised direction to the rotation member in a state where the opening/closing body is closed.

3. The medium transporting device according to claim 2 ,

wherein the opening/closing body has

a sliding contact surface which is positioned on an upper side with respect to the supporting portion and with which the supporting portion is slidingly in contact when the opening/closing body is opened/closed, and

a first engaging portion which is positioned so as to interpose the supporting portion between the opening/closing body and the sliding contact surface in a state where the opening/closing body is closed, and

wherein when the opening/closing body is opened from a closed state, the first engaging portion applies a force to the supporting portion in a raised direction.

4. The medium transporting device according to claim 3 ,

wherein the opening/closing body includes a second engaging portion which is positioned at a location farther from the supporting portion than the first engaging portion below the supporting portion in a state where the opening/closing body is closed, and

wherein an inclined surface is formed below the second engaging portion, and thus the second engaging portion rides over the supporting portion and enters below the supporting portion by the inclined surface when the opening/closing body is closed from a state where the opening/closing body is open and the rotation member falls down.

5. The medium transporting device according to claim 1 ,

wherein the rotation member includes a cam follower on a rotation center side thereof, and

wherein the pressing unit includes

a cam which presses the cam follower, and

a pressing member that applies a pressing force to the cam.

6. The medium transporting device according to claim 1 ,

wherein a plurality of rotation angles of the rotation member are set in which the force that the supporting portion of the rotation member applies to the opening/closing body in the opening direction and the force that the opening/closing body tries to close are balanced with each other.

7. The medium transporting device according to claim 6 ,

wherein the opening/closing body includes a sliding contact surface which is positioned on an upper side with respect to the supporting portion and with which the supporting portion is slidingly in contact when the opening/closing body is opened/closed, and

wherein a plurality of protrusions are provided on the sliding contact surface with a predetermined gap in a sliding contact direction with the supporting portion.

8. An image reading apparatus comprising:

a reading unit that reads a medium; and

the medium transporting device according to claim 1 that transports the medium.

9. An opening/closing device comprising:

a main body portion;

an opening/closing body that is capable of being opened/closed at least a portion of the main body portion by rotating with respect to the main body portion; and

a holding unit that holds the opening/closing body in a state where the opening/closing body is open,

wherein the holding unit includes:

a rotation member that has a supporting portion which is capable of being displaced between a state of being raised up and a state of being dropped down by rotation thereof, supports the opening/closing body, and applies a force to the opening/closing body in an opening direction by the supporting portion engaging with the opening/closing body, and

a pressing unit that presses the rotation member in the raised direction, and

wherein the holding unit further includes a configuration in which a force that the supporting portion applies to the opening/closing body in the opening direction due to a pressing force to the rotation member generated by the pressing unit and a force that the opening/closing body tries to close are balanced with each other according to a predetermined rotation angle of the rotation member,

wherein the supporting portion of the rotation member is capable of engaging with and disengaging from the opening/closing body and disengages from the opening/closing body by the rotation angle of the rotation member reaching the upper limit when the opening/closing body exceeds a predetermined opening angle.

10. A medium transporting device comprising:

a main body portion that constitutes a medium transporting path through which a medium is transported;

an opening/closing body that is provided to be rotatable with respect to the main body portion, forms the medium transporting path between the opening/closing body and the main body portion by closing thereof, and exposes the medium transporting path by opening thereof; and

a holding unit that holds the opening/closing body in a state where the opening/closing body is open,

wherein the holding unit includes:

a rotation member that has a supporting portion which is capable of being displaced between a state of being raised up and a state of being dropped down by rotation thereof and supports the opening/closing body and applies a force to the opening/closing body in an opening direction by the supporting portion engaging with the opening/closing body, and

a pressing unit that presses the rotation member in the raised direction and applies a pressing force to the opening/closing body in the opening direction by the rotation member, and

wherein the holding unit further includes a configuration in which a force that the supporting portion applies to the opening/closing body in the opening direction due to the pressing force to the rotation member generated by the pressing unit and a force that the opening/closing body tries to close are balanced with each other according to a predetermined rotation angle of the rotation member,

wherein the opening/closing body includes a sliding contact surface which is positioned on an upper side with respect to the supporting portion and with which the supporting portion is slidingly in contact when the opening/closing body is opened/closed, and

wherein a plurality of protrusions are provided on the sliding contact surface with a predetermined gap in a sliding contact direction with the supporting portion.