Toner replenishing device having a coil spring and spherical member at end of coil spring for loosening toner and image forming apparatus provided therewith

An image forming apparatus, comprising:

• an image carrier which carries an electrostatic latent image;
• a toner container which stores toner for replenishment, and has a discharge port of toner;
• a developing device which has a replenishment port of toner, and supplies toner to the image carrier;
• a toner conveying portion which conveys the toner in a region between the discharge port and the replenishment port, a toner conveying portion including a vertical conveying portion for vertically conveying the toner, and a horizontal conveying portion for receiving the toner from the vertical conveying portion and horizontally conveying the received toner;
• a conveying member which is disposed in the horizontal conveying portion, the conveying member including a shaft member extending in an extending direction of the horizontal conveying portion, and a projecting portion formed around the shaft member, the conveying member being adapted to convey the toner by being rotated about an axis of the shaft member;
• a toner loosening member which is disposed in the vertical conveying portion to be swingable up and down;
• and
• a swinging member which is disposed at a connecting portion between the vertical conveying portion and the horizontal conveying portion to be contactable with the conveying member and the toner loosening member, wherein
• the swinging member swings up and down in accordance with a movement of the swinging member which is operable to change a contact portion of the swinging member with respect to the conveying member between the shaft member and the projecting portion, as the conveying member is rotated,
• the toner loosening member swings up and down, as the swinging member swings
• the conveying member is a conveying screw having the shaft member, and a blade portion formed spirally around the shaft member, as the projecting portion,
• the swinging member is a spherical member that is contacted with the conveying member by the weight of the swinging member, a lower part of the spherical member being contacted with the conveying screw,
• the toner loosening member is a member having a coil spring shape, the toner loosening member having a circular ring portion at a lower end thereof, the circular ring portion having an inner diameter smaller than a diameter of the spherical member,
• the circular ring portion is slidably received at an upper part of the spherical member by the weight of the toner loosening member, and
• a horizontal movement of the spherical member is restricted by a wall surface for dividing the vertical conveying portion.