Paper feeding device

A paper feeding device, comprising:

• a lower housing;
• an upper housing disposed above the lower housing, the upper housing being spaced from the lower housing to form a paper feeding channel between the lower housing and the upper housing;
• a pickup assembly disposed to the lower housing, the pickup assembly including at least one pickup roller, and a top of the pickup roller projecting beyond a top surface of the lower housing and being located in the paper feeding channel;
• a separation assembly disposed to the upper housing and corresponding to a top of the pickup assembly, the separation assembly including at least one separation roller, and a bottom of the separation roller projecting under a bottom surface of the upper housing and being located in the paper feeding channel;
• a relay assembly disposed to the lower housing, and located to a downstream of the pickup assembly and the separation assembly which are partially located in the paper feeding channel, the relay assembly including a relay roller, and a top of the relay roller projecting beyond the top surface of the lower housing and being located in the paper feeding channel;
• a paper friction mechanism slidably disposed to the upper housing and corresponding to a top of the relay assembly, and located to the downstream of the pickup assembly and the separation assembly which are partially located in the paper feeding channel;
• an elastic element elastically disposed between the upper housing and a top of the paper friction mechanism;
• a paper speed detector fastened to the upper housing and located in front of the paper friction mechanism;
• a first paper feeding assembly disposed to the lower housing and located to a downstream of the relay assembly and the paper friction mechanism which are partially located in the paper feeding channel, the first paper feeding assembly including at least one feeding roller, and a top of the feeding roller projecting beyond the top surface of the lower housing and being located in the paper feeding channel;
• a second paper feeding assembly disposed to the upper housing and corresponding to a top of the first paper feeding assembly, and located to the downstream of the relay assembly and the paper friction mechanism which are partially located in the paper feeding channel, the second paper feeding assembly including at least one idle roller, and a bottom of the idle roller projecting under the bottom surface of the upper housing and being located in the paper feeding channel;
• a transmission assembly connected with the pickup assembly, the relay assembly and the first paper feeding assembly;
• a motor connected with the transmission assembly;
• and
• a control unit connected with the paper speed detector and the motor, the control unit controlling the paper speed detector to detect paper feeding speeds and the paper speed detector sending signals to the control unit for determining paper feeding conditions, the control unit controlling the motor to rotate, and the motor driving the pickup assembly, the relay assembly and the first paper feeding assembly to rotate by virtue of the transmission assembly, and the first paper feeding assembly driving the second paper feeding assembly to rotate, the control unit being capable of adjusting rotating speeds of the motor, so that the paper feeding speeds being stabilized.