Patent ID: 7979013

Claim:
A developing device comprising: a developer carrier for carrying a developer and conveying said developer to an opposing portion opposing a latent image carrier; a developing portion having a developer supply/collection member for supplying said developer while rotating in contact with said developer carrier and collecting said developer from said developer carrier; a developer accommodating portion provided above said developing portion and accommodating developer to be supplied to said developing portion; a partitioning member provided between said developing portion and said developer accommodating portion and having an opening portion; an accommodating portion developer agitating member disposed above said partitioning member for agitating said developer in said developer accommodating portion; a developing portion developer agitating member disposed below said partitioning member for agitating said developer in said developing portion; a collected developer storage portion forming portion for forming a storage space for said developer collected from said developer carrier by said developer supply/collection member within a fixed distance of said developer supply/collection member such that said collected developer moves to the vicinity of said developing portion developer agitating member in accordance with a developer flow generated by the rotation of said developer supply/collection member; and a casing for accommodating and holding all of the above, wherein a pre-incorporation component, separately formed from the casing, formed by integrating said partitioning member, a bearing portion for supporting a side of said developing portion developer agitating member or said accommodating portion developer agitating member that does not receive a drive force, and said collected developer storage portion forming portion is incorporated into said casing.