Apparatus and method for adjusting concentration of liquid developer

A liquid developer concentration adjusting apparatus, comprising:

• a concentration adjusting container having an opening;
• a developer supplying mechanism which is connected to the concentration adjusting container and is adapted to supply a liquid developer whose concentration is to be adjusted into the concentration adjusting container;
• a first liquid supplying mechanism which is connected to the concentration adjusting container and is adapted to supply a first supply liquid, whose concentration is higher than a desired liquid developer concentration, to the concentration adjusting container at a variable supply speed;
• a second liquid supplying mechanism which is connected to the concentration adjusting container and is adapted to supply a second supply liquid, whose concentration is lower than the desired liquid developer concentration, to the concentration adjusting container at a variable supply speed;
• a physical property detector which is adapted to detect a physical property which depends on concentration of the liquid developer in the concentration adjusting container;
• an OF detector which is adapted to detect a presence or absence of overflow of the liquid developer through the opening;
• and
• a controller which is adapted to control a supply speed of the first supply liquid supplied by the first liquid supplying mechanism or the second supply liquid supplied by the second liquid supplying mechanism depending on an output of the OF detector,
• wherein the developer supplying mechanism is adapted to supply the liquid developer whose concentration is to be adjusted at a variable supply speed, and the controller is adapted to control the supply speed of the liquid developer supplied by the developer supplying mechanism depending on the output of the OF detector, and wherein the controller controls the supply speed of the liquid developer supplied by the developer supplying mechanism to be lower as the physical property detected by the physical property detector reaches closer to a target value.

A method for adjusting concentration of liquid developer, the method comprising:

• supplying a liquid developer whose concentration is to be adjusted to a concentration adjusting container having a sidewall and an opening;
• supplying a first supply liquid whose concentration is higher than a desired liquid developer concentration to the concentration adjusting container;
• supplying a second supply liquid whose concentration is lower than the desired liquid developer concentration to the concentration adjusting container;
• stirring the liquid developer stored in the concentration adjusting container, wherein the liquid developer is raised along the sidewall;
• detecting, when stirring the liquid developer, a stirring load as a physical property which depends on concentration of the liquid developer in the concentration adjusting container;
• detecting a presence or absence of overflow of the liquid developer, which is raised by the stirring along the sidewall up to a level defined by a position of the opening, through the opening;
• and
• controlling a supply speed of the first supply liquid or the second supply liquid, based on the physical property detected during the detecting a stirring load process and the presence or absence of the overflow, so as to cause the physical property detected under the presence of the overflow to be a target value corresponding to the desired concentration.

A method for adjusting concentration of liquid developer, the method comprising:

• supplying a liquid developer whose concentration is to be adjusted to a concentration adjusting container having an opening;
• supplying a first supply liquid whose concentration is higher than a desired liquid developer concentration to the concentration adjusting container;
• supplying a second supply liquid whose concentration is lower than the desired liquid developer concentration to the concentration adjusting container;
• detecting a physical property which depends on concentration of the liquid developer in the concentration adjusting container;
• detecting a presence or absence of overflow of the liquid developer through the opening;
• and
• controlling a supply speed of the first supply liquid or the second supply liquid based on the physical property and the detected presence or absence of the overflow,
• wherein, during the controlling a supply speed process, the supply speed of the liquid developer whose concentration is to be adjusted to be lower as the detected physical property gets closer to a target value.