Document conveying device

A document conveying device comprising:

• a sheet feeding tray on which a document is placed;
• a discharge tray provided below the sheet feeding tray;
• a feeding roller which feeds the document one by one from the sheet feeding tray;
• a conveying mechanism which conveys the document from the sheet feeding tray to the discharge tray via a reading position;
• a lifting mechanism which lifts and lowers the sheet feeding tray;
• a discharge tray document sensor which detects the document on the discharge tray;
• a sheet feeding tray intermediate sensor which detects the sheet feeding tray at an intermediate position between a lower limit position and an upper limit position of the sheet feeding tray;
• and
• a control part which controls the lifting mechanism such that an upper surface of the document placed on the sheet feeding tray is pressed against the feeding roller when the conveying mechanism conveys the document, wherein
• the control part controls the lifting mechanism to lower the sheet feeding tray by a larger amount in a case where the document is not detected by the discharge tray document sensor when power is turned on than a case where the document is detected by the discharge tray document sensor, and
• the control part controls the lifting mechanism to lift or lower the sheet feeding tray such that the sheet feeding tray is detected by the sheet feeding tray intermediate sensor in the case where the document is detected by the discharge tray document sensor when the power is turned on.

A document conveying device comprising:

• a sheet feeding tray on which a document is placed;
• a discharge tray provided below the sheet feeding tray;
• a feeding roller which feeds the document one by one from the sheet feeding tray;
• a conveying mechanism which conveys the document from the sheet feeding tray to the discharge tray via a reading position;
• a lifting mechanism which lifts and lowers the sheet feeding tray;
• a discharge tray document sensor which detects the document on the discharge tray;
• a sheet feeding tray lower limit sensor which detects the sheet feeding tray at a lower limit position of the sheet feeding tray;
• and
• a control part which controls the lifting mechanism such that an upper surface of the document placed on the sheet feeding tray is pressed against the feeding roller when the conveying mechanism conveys the document, wherein
• the control part controls the lifting mechanism to lower the sheet feeding tray by a larger amount in a case where the document is not detected by the discharge tray document sensor when power is turned on than a case where the document is detected by the discharge tray document sensor, and
• in a case where the document is detected by the discharge tray document sensor during a waiting period and then the document is no longer detected by the discharge tray document sensor, after a predetermined time elapses, the control part controls the lifting mechanism to lower the sheet feeding tray until the sheet feeding tray is detected by the feeding tray lower limit sensor.

A document conveying device comprising:

• a sheet feeding tray on which a document is placed;
• a discharge tray provided below the sheet feeding tray;
• a feeding roller which feeds the document one by one from the sheet feeding tray;
• a conveying mechanism which conveys the document from the sheet feeding tray to the discharge tray via a reading position;
• a lifting mechanism which lifts and lowers the sheet feeding tray;
• a discharge tray document sensor which detects the document on the discharge tray;
• a sheet feeding tray document sensor which detects the document on the sheet feeding tray;
• and
• a control part which controls the lifting mechanism such that an upper surface of the document placed on the sheet feeding tray is pressed against the feeding roller when the conveying mechanism conveys the document, wherein
• the control part controls the lifting mechanism to lower the sheet feeding tray by a larger amount in a case where the document is not detected by the discharge tray document sensor when power is turned on than a case where the document is detected by the discharge tray document sensor, and
• in a case where the document is not detected by the discharge tray document sensor during a waiting period, the document is then detected by the discharge tray document sensor and the document is not detected by the sheet feeding tray document sensor, the control part controls the lifting mechanism to position the sheet feeding tray according to an amount of the document stacked on the discharge tray.