Paper feeding device

A paper feeding device, comprising:

• a pickup mechanism for picking up paper and transmitting the paper backward;
• a conveying mechanism disposed behind the pickup mechanism for conveying the paper transmitted by the pickup mechanism backward;
• a separation mechanism disposed behind the conveying mechanism for separating the paper conveyed by the conveying mechanism and transmitting the separated paper backward;
• a feeding mechanism disposed behind the separation mechanism for feeding the paper transmitted by the separation mechanism backward;
• a transmission mechanism electrically connected with and rotatably driving the pickup mechanism, the conveying mechanism, the separation mechanism and the feeding mechanism;
• and
• an ultrasonic circuit unit disposed between the separation mechanism and the transmission mechanism, the ultrasonic circuit unit including:
• an ultrasonic detecting module for detecting paper signals,
• an amplifying circuit unit electrically connected with the ultrasonic detecting module for receiving and amplifying the paper signals into amplified paper signals,
• a paper density detecting unit electrically connected with the amplifying circuit unit for receiving and analyzing the amplified paper signals to obtain a density of each piece of paper to determine a thickness of the each piece of paper and output paper density signals,
• an analog-to-digital converter electrically connected with the paper density detecting unit for converting the paper density signals into digital signals,
• a driving unit electrically connected with and driving the transmission mechanism to rotate, and
• a processor electrically connected with the analog-to-digital converter and the driving unit, the processor receiving the digital signals from the analog-to-digital converter and controlling the driving unit based on the digital signals;
• wherein the processor controls the driving unit to modulate rotation speeds of the transmission mechanism based on the digital signals according to different thickness of the paper determined by the paper density detecting unit, the ultrasonic circuit unit further includes a paper quantity detecting unit electrically connected with the amplifying circuit unit for detecting a quantity of the amplified paper signals, and the analog-to-digital converter is electrically connected with the paper quantity detecting unit.

A paper feeding device, comprising:

• a pickup mechanism for picking up paper and transmitting the paper backward;
• a conveying mechanism disposed behind the pickup mechanism for conveying the paper transmitted by the pickup mechanism backward;
• a separation mechanism disposed behind the conveying mechanism for separating the paper conveyed by the conveying mechanism and transmitting the separated paper backward;
• a feeding mechanism disposed behind the separation mechanism for feeding the paper transmitted by the separation mechanism backward;
• a transmission mechanism electrically connected with and rotatably driving the pickup mechanism, the conveying mechanism, the separation mechanism and the feeding mechanism;
• and
• an ultrasonic circuit unit disposed between the separation mechanism and the transmission mechanism, the ultrasonic circuit unit including:
• an ultrasonic detecting module for detecting paper signals,
• an amplifying circuit unit electrically connected with the ultrasonic detecting module for receiving and amplifying the paper signals into amplified paper signals,
• a paper density detecting unit electrically connected with the amplifying circuit unit for receiving and analyzing the amplified paper signals to obtain a density of each piece of paper to determine a thickness of the each piece of paper and output paper density signals,
• an analog-to-digital converter electrically connected with the paper density detecting unit for converting the paper density signals into digital signals,
• a driving unit electrically connected with and driving the transmission mechanism to rotate, and
• a processor electrically connected with the analog-to-digital converter and the driving unit, the processor receiving the digital signals from the analog-to-digital converter and controlling the driving unit based on the digital signals;
• wherein the processor controls the driving unit to modulate rotation speeds of the transmission mechanism based on the digital signals according to different thickness of the paper determined by the paper density detecting unit, the pickup mechanism includes a pickup driving pulley and a pickup following pulley, the pickup following pulley is disposed above the pickup driving pulley, and the pickup driving pulley is driven by the transmission mechanism.