JP2002287576A - Image forming apparatus and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of saving energy when the motor unit is turned off while enhancing power efficiency as a motor unit by eliminating unnecessary power loss in the motor unit and preventing shortning of its component life. SOLUTION: A power source (24 V) for power system is supplied to a driving means 9 of a motor 7 through a power supply line 5 and a power source (5 V) for control system is supplied to a control part 8 through a power supply line 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electrophotographic copying machine and a printer, and a control method thereof, and more particularly to a power supply method to a motor unit having a control circuit.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration of a conventional example. In FIG. 4, reference numeral 1 denotes a control board of an electrophotographic image forming apparatus, which has a CPU 2 for controlling the operation of the image forming apparatus main body. ing. Reference numeral 6 denotes a motor unit, which includes a motor 7, a driving unit 9 including a driving transistor for driving the motor 7, and a control unit 8 for controlling the driving of the driving unit 9.

The speed control means 8a of the control unit 8
Drives the drive means 9 in accordance with the rotation instruction signal of the motor 7 transmitted through the signal line 3 to rotate the motor 7, and based on the speed detection signal detected by the speed detection means 8b, the motor 7 The driving of the driving means 9 is controlled so as to achieve a predetermined rotation speed. The speed controller 8a controls the driving of the driver 9 in synchronization with the reference clock signal generated by the reference clock generator 8c.

A power supply (2) for a power system is supplied from the control board 1 side to the motor unit 6 through a power supply line 15.
4V) is supplied, and DC / DC in the motor unit 6 is supplied.
The power supply for the control system is generated by the converter 20.

[0005]

However, in the above-described image forming apparatus, since the power supply for the control system is made from the power supply for the power system in the motor unit, the power loss in the DC-DC converter section is caused. And the power efficiency of the motor unit cannot be increased.

For example, in the case of a motor having a power supply voltage of +24 V and a power supply of a control circuit of +5 V and 0.5 A, (24
−5) × 0.5 = 9.5 (W) of power is a loss in the DC-DC converter unit.

In an electrophotographic image forming apparatus, a motor for rotating a polygon mirror, which polarizes a laser beam, hermetically seals the periphery to prevent dust on the mirror and lens. There is a problem that the life is shortened.

Further, in the motor for driving the photosensitive drum and the fixing device in the electrophotographic image forming apparatus, the size of the apparatus has recently been reduced, and the heat of the motor also raises the temperature inside the apparatus and shortens the life of parts. There was a point.

Further, even when the motor is not driven, the internal circuit is operating, so that energy is not saved.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. The present invention eliminates unnecessary power loss in a motor unit, improves power efficiency as a motor unit, and reduces the life of parts. It is an object of the present invention to provide an image forming apparatus that prevents a decrease and saves energy when a motor is not driven, and a control method thereof.

[0011]

An image forming apparatus and a control method thereof according to the present invention are configured as follows.

(1) In an electrophotographic image forming apparatus, two types of power supplies for a power system and a control system are separately supplied to a drive motor unit.

(2) In the image forming apparatus of (1), the power supply to the drive motor unit is cut off in accordance with the operation mode of the apparatus main body.

(3) In the image forming apparatus of the above (1), two kinds of power supplies for the power system and the control system can be individually supplied or cut off according to the operation mode of the apparatus main body.

(4) In the method of controlling an electrophotographic image forming apparatus, two types of power supplies, one for a power system and one for a control system, are separately supplied to a drive motor unit, and the operation mode of the main body of the image forming apparatus is set. Accordingly, the power supply to the driving motor unit is cut off.

(5) In the method for controlling an electrophotographic image forming apparatus, two types of power supplies for a power system and a control system are separately supplied to a drive motor unit, and the two types of power are supplied to the image forming apparatus. The apparatus is individually supplied or cut off according to the operation mode of the apparatus body.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a block diagram showing a configuration according to a first embodiment. The same components as those in FIG. 4 are denoted by the same reference numerals. Referring to FIG. 1, reference numeral 1 denotes a control board of an electrophotographic image forming apparatus, which controls the operation of the main body of the image forming apparatus.
U2. Reference numeral 6 denotes a motor unit, which includes a motor 7, a driving unit 9 including a driving transistor for driving the motor 7, and a control unit 8 for controlling the driving of the driving unit 9.

A power supply (24 V) for a power system is supplied to the driving means 9 through a power supply line 5. The control unit 8 supplies a power supply (5 V) for the control system through the power supply line 4.
Is supplied. The power supply for the control system is not a power supply dedicated to the motor unit 6 but a power supply for the CPU 2 and also used in the control board 1.

Reference numeral 3 denotes a signal line for instructing the rotation of the motor 7, and a speed control means 8a of the control unit 8
Drives the drive means 9 in accordance with the rotation instruction signal of the motor 7 transmitted through the signal line 3 to rotate the motor 7, and based on the speed detection signal detected by the speed detection means 8b, the motor 7 The driving of the driving means 9 is controlled so as to achieve a predetermined rotation speed. The speed controller 8a controls the driving of the driver 9 in synchronization with the reference clock signal generated by the reference clock generator 8c.

With the above configuration, a DC for generating a power supply for the control system from a power supply for the power system in the motor unit 6 again
-A DC converter is not required, and unnecessary power loss in the motor unit can be eliminated, and power efficiency as the motor unit can be improved.

(Second Embodiment) FIG. 2 is a block diagram showing a configuration according to a second embodiment. Referring to FIG. 2, in this embodiment, a transistor is added to the configuration of the first embodiment and a motor is added. A case where the power supply to the unit can be turned ON / OFF will be described. Note that the same components as those in FIG. 1 are denoted by the same reference numerals and description thereof will be omitted.

In FIG. 2, reference numeral 10 denotes a signal line for turning on / off the power supply. The signal line 10 is connected to an I / O port of the CPU 2, and the CPU 2 receives transistors 11 and 12 via a signal line 10 in response to a power on / off signal. On and off.

When the motor 7 is rotated, the transistors 11 and 12 are turned on by a power on / off signal, and then the motor 7 is rotated by turning on a rotation instruction signal. When it is not necessary to rotate the motor 7, the power on / off signal is turned off, and the motor unit 6 is turned off.
Cut off the power supply to the

Thus, energy saving can be achieved when the motor is not driven.

(Third Embodiment) FIG. 3 is a block diagram showing a configuration according to a third embodiment. The difference from the second embodiment is that a power supply for a control system and a power supply for a power system are separately provided. That is, it can be turned on and off. 1 and 2
The same components as those described above are denoted by the same reference numerals and description thereof will be omitted.

In FIG. 3, reference numerals 13 and 14 denote signal lines for turning on / off the power for the control system and the power system, respectively.
Turns on / off the transistors 11 and 12 by the power on / off signal via the signal lines 13 and 14, respectively.

As described above, in the first to third embodiments, it is not necessary to make the power supply for the control system in the motor unit from the power supply for the power system, and the power loss in the conventional DC-DC converter is eliminated. Thus, the power efficiency of the motor unit can be improved.

Further, by providing a means for interrupting power supply to the motor unit, power consumption when the motor is not driven can be reduced.

[0029]

As described above, according to the present invention,
This has the effect of eliminating unnecessary power loss in the motor unit, increasing the power efficiency of the motor unit, preventing a reduction in component life, and saving energy when the motor is not driven.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration according to a first embodiment.

FIG. 2 is a block diagram showing a configuration according to a second embodiment;

FIG. 3 is a block diagram showing a configuration according to a third embodiment;

FIG. 4 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 control board 2 CPU 3 signal line 4 power supply line (for control system) 5 power supply line (for power system) 6 motor unit 7 motor 8 control unit 9 driving means

Claims (5)

[Claims] 1. An electrophotographic image forming apparatus, comprising:
An image forming apparatus, wherein two types of power supplies for a power system and a control system are separately supplied to a drive motor unit. 2. The image forming apparatus according to claim 1, wherein power supply to a driving motor unit is cut off according to an operation mode of the apparatus main body. 3. The image forming apparatus according to claim 1, wherein two types of power supplies for a power system and a control system can be individually supplied or cut off according to an operation mode of the apparatus main body. 4. A method of controlling an electrophotographic image forming apparatus, wherein two types of power supplies for a power system and a control system are separately supplied to a driving motor unit, and the power is supplied in accordance with an operation mode of the image forming apparatus main body. And shutting off the power supply to the driving motor unit. 5. A control method for an electrophotographic image forming apparatus, wherein two types of power supplies for a power system and a control system are separately supplied to a driving motor unit, and the two types of power are supplied to the image forming apparatus. A method for controlling an image forming apparatus, wherein the supply or the supply is individually performed according to an operation mode of an apparatus main body.