Sheet supplying apparatus, sheet processing apparatus employing the same, and image forming apparatus

1. A sheet supplying apparatus, comprising:

a loading table to accommodate one or more sheets of a printing medium;

a pickup member to pick up a sheet from the loading table;

an alignment member pivotable to an alignment location for blocking and aligning a fore-end of a sheet on the loading table, and to a transport-allowing location for allowing a sheet picked up by the pickup member to be transported;

a pivoting shaft to which the alignment member is coupled;

a cam gear comprising a gear portion, a tooth-omitted portion, and a cam portion to switch the alignment member between the alignment location and the transport-allowing location at first and second rotating positions of the cam gear such that the alignment member pivots away from the cam gear when the alignment member is switched to the alignment location and pivots toward the cam gear when the alignment member is switched to the transport-allowing location;

a lever, coupled to the pivoting shaft, to selectively contact the cam portion, wherein:

when the cam gear is rotated to the first rotating position, the cam portion interacts with the lever to position the alignment member at the alignment location, and

when the cam gear is rotated to the second rotating position, the cam portion is to be spaced apart from the lever to switch the alignment member to the transport-allowing location;

a main gear;

a swing arm pivotable about a same axis as a rotation axis of the main gear; and

first and second swing gears supported by the swing arm to interlock with the main gear, to selectively interlock with the gear portion according to a rotating direction of the main gear, and to rotate the cam gear to the first and second rotating positions.

2. The sheet supplying apparatus of claim 1 , wherein

when the alignment member is positioned at the alignment location, the second swing gear contacts an idle gear positioned on the tooth-omitted portion, and

when the alignment member is positioned at the transport-allowing location, the first swing gear is positioned on the tooth-omitted portion and the second swing gear is spaced apart from the idle gear.

3. The sheet supplying apparatus of claim 1 , further comprising:

a holder to support the pickup member and be pivotable to a pickup location for allowing the pickup member to contact the sheet on the loading table, and a separating location for spacing the pickup member apart from the sheet on the loading table; and

an elastic member to apply to the holder an elastic force in a direction allowing the holder to be pivoted to the pickup location,

wherein the alignment member is to apply a force to the holder such that the holder is pivoted to the separating location, when the alignment member is switched from the transport-allowing location to the alignment location.

4. The sheet supplying apparatus of claim 3 , wherein, when the alignment member is positioned at the alignment location, the alignment member supports the holder such that the holder is maintained at the separating location.

5. The sheet supplying apparatus of claim 4 , wherein, when the alignment member is switched from the alignment location to the transport-allowing location, the holder is pivoted to the pickup location by the elastic force of the elastic member.

6. The sheet supplying apparatus of claim 1 , further comprising an idle gear interposed between one of the first and second swing gears and the gear portion.

7. The sheet supplying apparatus of claim 1 , further comprising an elastic member to apply to the pivoting shaft an elastic force in a direction allowing the alignment member to be switched to the transport-allowing location.

8. The sheet supplying apparatus of claim 1 , further comprising a stopper to stop the alignment member so that the alignment member is not excessively pivoted beyond the transport-allowing location.

9. A sheet processing apparatus, comprising:

the sheet supplying apparatus of claim 1 ; and

a sheet processing unit to perform processing on a sheet supplied by the sheet supplying apparatus.

10. The sheet processing apparatus of claim 9 , wherein the sheet processing unit comprises a read unit to read an image from the sheet.

11. The sheet processing apparatus of claim 9 , wherein the sheet processing unit comprises a printing unit to print an image on the sheet.