Image forming apparatus utilizing replaceable image forming cartridge and detecting means
AssigneeMinolta Camera Kabushiki Kaisha
InventorTatsuya Eguchi
Life of this patent
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Abstract
An image forming apparatus of a type employing the replaceable image forming unit includes a detecting device for detecting an amount of rays of light having passed across a developer hopper, and a determining device for comparing the amount of light detected by the detecting device with a predetermined threshold value to determine the presence or absence of the image forming unit within the pocket. The detection of whether or not the image forming unit has been loaded into the pocket is possible regardless of the condition of the stirrer blade assembly within the hopper, that is, regardless of whether or not the stirred blade assembly is being driven.
Claims14
An image forming apparatus of a type utilizing a replaceable image forming unit, said image forming unit including a developer hopper for accommodating a mass of developing material, said apparatus comprising:
- means for detecting rays of light having passed across the developer hopper;
- and
- means for comparing the amount of light detected by the detecting means with a predetermined threshold value to determine whether or not the image forming unit is installed, depending on a result of detection performed thereby.
An image forming apparatus which comprises:
- a replaceable image forming unit including a developer hopper for accommodating a mass of developing material therein, said developer hopper having an incident window through which external rays of light enter the developer hopper and an exit window through which the rays of light having entered the developer hopper emerge outwardly;
- means for stirring the developing material within the developer hopper;
- a pocket defining structure having a pocket defined therein for replaceably receiving therein the image forming unit;
- a light receiving means disposed so as to confront the exit window of the developer hopper;
- means for determining whether or not the image forming unit is installed within the pocket in accordance with the amount of the rays of light received by the light receiving means without regard to the operation of the stirring means;
- and
- means for determining the amount of developing material contained in the developer hopper in accordance with the amount of the rays of light received by the light receiving means during the operation of the stirring means.
An image forming apparatus which comprises:
- a replaceable image forming unit including a developer hopper for accommodating a mass of developing material therein, said developer hopper having an incident window through which external rays of light enter the developer hopper, an exit window through which the rays of light having entered the developer hopper emerge outwardly, and means for stirring the developing material within the developer hopper, at least one of said incident and exit windows being made of a semitransparent material;
- a pocket defining structure having a pocket defined therein for replaceably receiving therein the image forming unit;
- a light emitting means disposed so as to confront the incident window of the developer hopper;
- a light receiving means disposed so as to confront the exit window of the developer hopper;
- a first means for detecting the amount of the rays of light received by the light receiving means and for determining, in dependence on the amount of the rays of light received by the light receiving means, whether or not the image forming unit is installed within the pocket, when the image forming apparatus is electrically powered on;
- and
- a second means for determining the amount of developing material contained in the developer hopper in dependence on a result of detection by the light receiving means while the stirring means is operated, in the event that the first means determines that the image forming unit has been installed within the pocket.
An image forming unit adapted to be replaceably installed in an image forming apparatus comprising a detecting means having a light emitting element and a light receiving element for detecting whether or not the image forming unit is installed in the image forming apparatus and also the amount of developing material, said unit comprising:
- a developer hopper for accommodating a mass of the developing material;
- an incident window through which external rays of light enter the developer hopper;
- and
- an exit window through which the external rays of light having entered the developer hopper emerge outwardly, at least one of said incident and exit windows being made of semitransparent material;
- said incident and exit windows being arranged on the developer hopper such that the windows are in respective alignment with the light emitting element and the light receiving element when the developer hopper is installed in the image forming apparatus.
Dependencies are inferred from the claim text.