Sheet feeding device, image forming apparatus incorporating the sheet feeding device, and image forming system incorporating the sheet feeding device

A sheet feeding device comprising:

• a sheet loader on which a bundle of sheets is to be loaded;
• a loader elevating device configured to move the sheet loader in a vertical direction;
• a sheet presence detector configured to detect whether the bundle of sheets is loaded on the sheet loader;
• and
• circuitry configured to determine whether the bundle of sheets is loaded on the sheet loader based on a detection result of the sheet presence detector, and to control movement of the loader elevating device,
• the circuitry being configured to cause the loader elevating device to lift the sheet loader to a second position that is above a first position in the vertical direction of the sheet loader, in response to a detection result of the sheet presence detector indicating that a sheet is absent on the sheet loader at the first position,
• the circuitry being configured not to determine that the sheet is absent on the sheet loader when the circuitry causes the loader elevating device to lower the sheet loader from the second position to the first position after the circuitry causes the loader elevating device to lift the sheet loader to the second position
• wherein the circuitry includes:
• a first position determiner configured to determine whether the sheet is located at a level of the first position;
• and
• a second position determiner configured to determine whether the sheet is located at a level of the second position;
• wherein the sheet feeding device further includes an air blower configured to blow air toward an upper end portion of the bundle of sheets loaded on the sheet loader to lift the sheet,
• wherein the loader elevating device is configured to cause the sheet loader to stop moving in the vertical direction and complete an initial operation of the sheet feeding device based on respective detection results of the first position determiner and the second position determiner, and
• wherein, the circuitry is configured to cause the loader elevating device to move the sheet loader in the vertical direction based on a detection result of the second position determiner, as a sheet feeding operation starts and the air blower starts blowing air.

A sheet feeding device comprising:

• a sheet loader on which a bundle of sheets is to be loaded;
• a loader elevating device configured to move the sheet loader in a vertical direction;
• a sheet presence detector configured to detect whether the bundle of sheets is loaded on the sheet loader;
• and
• circuitry configured to determine whether the bundle of sheets is loaded on the sheet loader based on a detection result of the sheet presence detector, and to control movement of the loader elevating device,
• the circuitry being configured to cause the loader elevating device to lift the sheet loader to a second position that is above a first position in the vertical direction of the sheet loader, in response to a detection result of the sheet presence detector indicating that a sheet is absent on the sheet loader at the first position,
• the circuitry being configured not to determine that the sheet is absent on the sheet loader when the circuitry causes the loader elevating device to lower the sheet loader from the second position to the first position after the circuitry causes the loader elevating device to lift the sheet loader to the second position;
• and
• wherein the circuitry includes:
• a first position determiner configured to determine whether the sheet is located at a level of the first position;
• and
• a second position determiner configured to determine whether the sheet is located at a level of the second position;
• wherein the sheet feeding device further includes a first sheet detector configured to detect the sheet, and a second sheet detector disposed above the first sheet detector and configured to detect the sheet,
• wherein the first position determiner is configured to determine whether the sheet is located at the level of the first position based on a detection result of the first sheet detector, and
• wherein the second position determiner is configured to determine whether the sheet is located at the level of the second position based on a detection result of the second sheet detector.