Image Forming Apparatus, and Control Method of Image Forming Apparatus

Abstract

An image forming apparatus, having: a rotary developing unit, to and from which a plurality of developing cartridges storing developers are attached and detached and which moves one of the attached developing cartridges to a developing position by being rotated around a rotation axis; a drive motor that rotates the rotary developing unit; and a controller that controls a torque of the drive motor in response to a condition of the developing cartridges to be attached to the rotary developing unit or a condition of the rotary developing unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Hereinafter, embodiments of the image forming apparatus will be described with reference to the drawings,

FIG. 1 is a longitudinal side view showing a schematic configuration of a color laser printer 10;

FIG. 2 is a block diagram showing a schematic electrical configuration of a controller 34;

FIG. 3 is a perspective view showing a substantial part of a rotary developing unit 14;

FIG. 4 shows an attachment condition X and a phase θ;

FIG. 5 shows relationships among the attachment condition X, the phase θ and a reference current amount I (X, θ) ;

FIG. 6 shows a schematic relationship between a residual amount of toner W and an adjustment factor k (W;

FIG. 7 shows a schematic relationship between a rotational acceleration a and a compensation factor C(a);

FIG. 8 shows a flow of calculation of the amount of current to be fed to a rotary drive motor;

FIG. 9 shows an example of control of the current to be fed to the rotary drive motor; and

FIG. 10 shows an example of control of the current to be fed to the rotary drive motor.

Claims

1. An image forming apparatus, comprising: a rotary developing unit, to and from which a plurality of developing cartridges storing developers are attached and detached and which moves one of the attached developing cartridges to a developing position by being rotated around a rotation axis;a drive motor that rotates the rotary developing unit; anda controller that controls a torque of the drive motor in response to a condition of the developing cartridges to be attached to the rotary developing unit and/or a condition of the rotary developing unit.

2. The image forming apparatus according to claim 1, wherein the torque of the drive motor is determined based on an amount of current to be fed to the drive motor, and the controller controls the torque of the drive motor by controlling the amount of current to be fed to the drive motor in response to the condition of the developing cartridges and/or the condition of the rotary developing unit.

3. The image forming apparatus according to claim 1, wherein the condition of the developing cartridges to be attached to the rotary developing unit and/or the condition of the rotary developing unit includes at least any one of: an attachment condition indicating the number of the developing cartridges attached to the rotary developing unit and the place of attachment of the developing cartridges; a residual amount of the developers of the developing cartridges attached to the rotary developing unit; a phase indicating the position of rotation of the rotary developing unit; and a rotational acceleration of the rotary developing unit.

4. The image forming apparatus according to claim 1, wherein the condition of the developing cartridges to be attached to the rotary developing unit and/or the condition of the rotary developing unit include all of: an attachment condition indicating the number of the developing cartridges attached to the rotary developing unit and the place or attachment of the developing cartridges; a residual amount of the developers of the developing cartridges attached to the rotary developing unit; a phase indicating the position of rotation of the rotary developing unit; and a rotational acceleration of the rotary developing unit.

5. The image forming apparatus according to claim 4, wherein the controller obtains a reference current amount on the basis of the attachment condition and the developer residual amount, obtains an adjustment factor on the basis of the phase, obtains a compensation factor on the basis of the rotational acceleration, calculates the amount of current by adding the compensation factor to a result obtained by multiplying the reference current amount by the adjustment factor, and controls the drive motor by means of the calculated current amount.

6. A control method of controlling a torque of a drive motor of an image forming apparatus comprising: a rotary developing unit, to and from which a plurality of developing cartridges storing developers are attached and detached and which moves one of the attached developing cartridges to a developing position by being rotated around a rotation axis;the drive motor that rotates the rotary developing unit; anda controller that controls the torque of the drive motors wherein the method comprises:a step in which the controller acquires a result of detecting a condition of the developing cartridges to be attached to the rotary developing unit and/or a condition of the rotary developing unit; anda step in which the controller controls the torque of the drive motor in response to the acquired detection result.

7. A program product for causing a computer to execute the control method described in claim 6.

8. A recording medium capable of being read by the computer recording the program described in claim 7.