Developing device and image forming apparatus provided with same
First Claim
1. A developing device comprising:
- a developer tank for containing a two-component developer; and
a toner supporting member, positioned so that part thereof is exposed through an opening of the developer tank, for carrying the two-component developer from the developer tank to the part that is exposed through the opening, the developing device developing an electrostatic latent image with the two-component developer thus carried to the part that is exposed through the opening, and the electrostatic latent image being formed on a latent image bearing member of an image forming apparatus, wherein;
end gaps are small enough not to allow the two-component developer to flow out from the developer tank through either of end portions of the toner supporting member, and are narrower than a center gap, where the end gaps are smallest gaps between the end portions of the toner supporting member and the developer tank in a downstream of a nip portion between the toner supporting member and the latent image bearing member in a transportation direction of the two-component developer, the end gaps being in a direction perpendicular to the transportation direction, and the center gap is a smallest gap between the developer tank and a center portion of the toner supporting member, the center portion being a portion sandwiched between the end portions.
1 Assignment
0 Petitions
Accused Products
Abstract
A developing device is arranged such that Dg<ds<3Dg, and 3Dg<dc<6Dg, where ds is an end gap, Dg is an upstream gap, and dc is a center gap. The gap ds is a gap between a developer tank 4 and either end portion of a developing roller 1 in the downstream of a transportation direction of the developing roller 1. The end portion of the developing roller 1 is an end portion thereof with respect to a rotation direction of the developing roller 1. The gap Dg is a gap between the developing roller 1 and a doctor blade. The gap dc is a smallest gap between the developer tank 4 and the center portion b of the developing roller 1. With this arrangement, it is possible to prevent the toner scattering appropriately in the developing device for use of a two-component developer containing toner and carrier.
-
Citations
8 Claims
-
1. A developing device comprising:
- a developer tank for containing a two-component developer; and
a toner supporting member, positioned so that part thereof is exposed through an opening of the developer tank, for carrying the two-component developer from the developer tank to the part that is exposed through the opening, the developing device developing an electrostatic latent image with the two-component developer thus carried to the part that is exposed through the opening, and the electrostatic latent image being formed on a latent image bearing member of an image forming apparatus, wherein;end gaps are small enough not to allow the two-component developer to flow out from the developer tank through either of end portions of the toner supporting member, and are narrower than a center gap, where the end gaps are smallest gaps between the end portions of the toner supporting member and the developer tank in a downstream of a nip portion between the toner supporting member and the latent image bearing member in a transportation direction of the two-component developer, the end gaps being in a direction perpendicular to the transportation direction, and the center gap is a smallest gap between the developer tank and a center portion of the toner supporting member, the center portion being a portion sandwiched between the end portions. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- a developer tank for containing a two-component developer; and
-
8. An image forming apparatus, comprising a developing device, wherein:
-
the developing device comprises;
a developer tank for containing a two-component developer; and
a toner supporting member, positioned so that part thereof is exposed through an opening of the developer tank, for carrying the two-component developer from the developer tank to the part that is exposed through the opening, the developing device developing an electrostatic latent image with the two-component developer thus carried to the part that is exposed through the opening, and the electrostatic latent image being formed on a latent image bearing member of an image forming apparatus, andend gaps are small enough not to allow the two-component developer to flow out from the developer tank through either of end portions of the toner supporting member, and are narrower than a center gap, where the end gaps are smallest gaps between the end portions of the toner supporting member and the developer tank in a downstream of a nip portion between the toner supporting member and the latent image bearing member in a transportation direction of the two-component developer, the end gaps being in a direction perpendicular to the transportation direction, and the center gap is a smallest gap between the developer tank and a center portion of the toner supporting member, the center portion being a portion sandwiched between the end portions.
-
Specification