DEVELOPMENT APPARATUS

Abstract

There is provided a development apparatus including a plurality of replenishment developer containers which accommodates a replenishment developer containing a toner to be replenished to a plurality of development devices, a plurality of replenishment developer conveyance paths which replenishes the replenishment developer in the plurality of replenishment developer containers to the plurality of development devices, a plurality of conveyance members provided in the plurality of replenishment developer conveyance paths, wherein a length of at least one conveyance path, of the plurality of replenishment developer conveyance paths, is different from that of other conveyance paths, and cohesion degree of a replenishment developer conveyed by the longest conveyance path, of the plurality of replenishment conveyance paths, is lower than cohesion degree of the replenishment developer conveyed by other conveyance paths.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing illustrating apart of an image forming apparatus equipped with a development unit according to an embodiment.

FIG. 2 is a drawing illustrating a toner replenishment path for every color from a toner cartridge which is a main part in the development unit according to the present embodiment, to a rotary type development unit.

FIG. 3 is a drawing schematically illustrating replenishment of toners with preferred cohesion degree capable of preventing toner cohesion clusters corresponding to hopper replenishment screws having different length for each of colors.

FIG. 4 shows Table 1, Table 2, Table 3 in which measurements in the first embodiment are summarized.

FIG. 5 shows Table 4, Table 5 in which measurements in the first embodiment are summarized.

FIG. 6 shows Table 6, Table 7 in which measurements in the second embodiment are summarized.

Claims

1. A development apparatus comprising: a plurality of development devices which develops an electrostatic image;a plurality of replenishment developer containers each of which accommodates replenishment developer containing a toner to be replenished to each of the plurality of development devices;a plurality of replenishment developer conveyance paths which communicates the plurality of replenishment developer containers with the plurality of development devices, and which replenishes the replenishment developer in the plurality of replenishment developer containers to each of the plurality of development devices; anda plurality of conveyance members which are provided in each of the plurality of replenishment developer conveyance paths for conveying the replenishment developer;wherein a length of at least one conveyance path, of the plurality of replenishment developer conveyance paths, is different from that of other conveyance paths, and cohesion degree of replenishment developer to be conveyed by a longest conveyance path, of the plurality of replenishment developer conveyance paths, is lower than cohesion degree of replenishment developer to be conveyed by other conveyance path.

2. The development apparatus according to claim 1, wherein particle diameter of replenishment developer to be conveyed by the longest conveyance path, of the plurality of replenishment developer conveyance paths, is larger than particle diameter of replenishment developer to be conveyed by other conveyance path.

3. The development apparatus according to claim 1, wherein cohesion degree of the replenishment developer is 30% or more and 70% or less.

4. The development apparatus according to claim 1, wherein cohesion degree of the replenishment developer is 40% or more and 60% or less.

5. The development apparatus according to claim 1, wherein the plurality of conveyance members have screw profile, and outside diameter of the plurality of conveyance members and inside diameter of the plurality of replenishment developer conveyance paths are arranged so as to have a predetermined clearance.