Toner conveyance device, and developing device and image forming apparatus including the same

A developing device, comprising:

• a developing container that stores a developer;
• a stirring conveyance member that stirs and conveys the developer in the developing container;
• a developer carrying member that is rotatably supported to the developing container and carries the developer in the developing container, and
• a toner replenishment section that replenishes the developing container with a toner,
• wherein
• the toner replenishment section is demountably mounted in an image forming apparatus and includes:
• a vertical conveyance portion that has an entry port and conveys the toner conveyed therein through the entry port by causing the toner to fall vertical, the entry port being formed at an upper end of the vertical conveyance portion and connected to a main-body-side conveyance path in the image forming apparatus;
• a horizontal conveyance portion that is connected to a lower end of the vertical conveyance portion and conveys the toner in a horizontal direction;
• a conveyance member that includes:
• a rotary shaft that is arranged in the horizontal conveyance portion along a conveyance direction of the toner;
• and
• a conveyance protrusion that is provided to protrude on an outer circumferential surface of the rotary shaft,
• the conveyance member using a drive source to rotate the rotary shaft so that the toner in the horizontal conveyance portion is conveyed in a direction along the rotary shaft by the conveyance protrusion;
• and
• a loosening member that is arranged in the vertical conveyance portion so as to be movable in a vertical direction,
• the loosening member is arranged so as to be movable between a first position below a connection portion between the main-body-side conveyance path and the entry port and a second position protruding upward beyond the connection portion and reciprocates in the vertical direction at each of the first position and the second position,
• the loosening member includes:
• a first loosening portion that is arranged on an upper side in the vertical conveyance portion and has an upper end opposed to the entry port;
• a second loosening portion that is arranged on a lower side in the vertical conveyance portion and has a lower end opposed to the conveyance member;
• and
• an annular portion that connects the first loosening portion to the second loosening portion and engages with an eccentric rotary shaft that is provided to protrude horizontally in the vertical conveyance portion, with a prescribed clearance provided between the annular portion and the eccentric rotary shaft in the vertical direction, and
• the eccentric rotary shaft rotates in contact with an inner circumferential surface of the annular portion, thus causing the loosening member to reciprocate in the vertical direction at each of the first position and the second position.