Recording-medium container and image forming apparatus

1. A recording-medium container, comprising:

a support portion that supports from below a recording medium stack loaded in the recording-medium container, and that lowers with loading of the recording medium stack;

a press portion disposed to be movable toward and away from a side of the recording medium stack loaded on the support portion, and pressed against the side;

an urging member that urges the press portion toward the recording medium stack when a quantity of the recording medium stack exceeds a predetermined load; and

a moving device that moves the press portion toward the recording medium stack when the support portion reaches a position below a predetermined position,

wherein the support portion lowers with the weight of the recording medium stack on the support portion,

wherein the urging member includes a rotating portion disposed below the support portion and a coupling portion that couples the rotating portion and the press portion with each other,

wherein, when the quantity of the recording medium stack loaded in the recording-medium container exceeds the predetermined load, the support portion presses a part of the rotating portion from above and rotates the rotating portion, and, rotation of the rotating portion urges the press portion toward the recording medium stack, and

wherein the coupling portion is wound around the rotating portion that rotates, and the press portion is urged toward the recording medium stack.

2. The recording-medium container according to claim 1 , wherein the urging member urges the press portion toward the recording medium stack using a weight of the recording medium stack.

3. The recording-medium container according to claim 2 , further comprising:

a support portion that supports from below the recording medium stack loaded in the recording-medium container,

wherein the support portion lowers with the weight of the recording medium stack on the support portion, and

wherein the urging member urges the press portion toward the recording medium stack using a force from the support portion that lowers.

4. The recording-medium container according to claim 1 ,

wherein the press portion comprises a plurality of press portions, and

wherein the urging member is connected to at least one of the plurality of press portions, and urges the at least one press portion toward the recording medium stack.

5. The recording-medium container according to claim 4 ,

wherein, when the at least one of the plurality of press portions is urged by the urging member to move toward the recording medium stack, another one of the plurality of press portions moves toward the recording medium stack in association with the at least one of the plurality of press portions.

6. The recording-medium container according to claim 4 ,

wherein the at least one of the plurality of press portions is a press portion handled and operated by an operator.

7. The recording-medium container according to claim 4 ,

wherein the recording-medium container is drawn out in a predetermined direction,

wherein the plurality of press portions are disposed at different positions in the predetermined direction, and

wherein the at least one of the plurality of press portions is a press portion located most downstream in the predetermined direction among the plurality of press portions.

8. The recording-medium container according to claim 1 ,

wherein the urging member includes a driving source that urges the press portion toward the recording medium stack, and a coupling portion that couples the driving source and the press portion with each other, and

wherein the coupling portion includes a tension spring that has one end connected to the press portion and another end connected to the driving source.

9. An image forming apparatus, comprising:

an image forming member that forms an image on a recording medium in a recording medium stack; and

a recording-medium container that accommodates the recording medium stack,

wherein the recording-medium container is the recording-medium container according to claim 1 .