JPH08149680A - Power supply control device for image forming apparatus and on-board sensor - Google Patents

Abstract

(57) [Summary] [Configuration] The CPU 31 inside the control unit 30
Power supply control unit 3 through O OUTPUT port
It is connected to No. 2 and outputs electric power to the sensors 3 and 10 by outputting a high level signal, and can supply electric power to the sensors 3 and 10 by outputting a low level signal. From the power supply control unit 32,
The power supply line capable of ON / OFF control is the sensor power supply unit 33.
It is connected to the. The sensor power supply unit 33 distributes the power supply to the cassette paper presence sensor 3 and the paper discharge sensor 10. [Effect] Since the power supply to the sensor can be controlled by having the state detection means (sensor) and the power supply control means to the sensor, the power supply to the sensor is stopped to save power when it is not necessary to operate the sensor. Can be planned.

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 using an electrophotographic process and the like, and a power supply control apparatus for an onboard sensor.

[0002]

2. Description of the Related Art Conventionally, a state detecting sensor incorporated in an image forming apparatus of this type has been directly connected to a power source.

[0003]

In the above-mentioned conventional example, since the power supply to the onboard sensor for state detection is always performed,
It had the following drawbacks.

(1) Since power is continuously supplied even when it is not necessary to operate the onboard sensor, power is wasted.

(2) Even when the on-board sensor fails, there is no means for detecting the presence / absence of a sensor failure, so that incorrect information may be provided to the user.

Therefore, in view of the above points, a first object of the present invention is to provide an image forming apparatus capable of turning on / off the power supply to the onboard sensor as needed.

A second object of the present invention is to provide a power supply control device for an onboard sensor which can accurately determine whether or not there is a failure on the onboard sensor.

[0008]

In order to achieve the first object of the present invention, the present invention provides an image forming apparatus for forming an image on a recording medium based on input image information. It is provided with state detection means for detecting an internal state and power supply control means for controlling power supply to the state detection means.

In order to achieve the second object, the present invention comprises a sensor for detecting an internal state of an image forming apparatus for forming an image on a recording medium, and a power supply control means for controlling power supply to the sensor. A failure detection unit that detects a failure of the sensor is provided, power supply to the sensor is stopped as necessary, and when the sensor fails, the fact is notified.

[0010]

According to the present invention, by providing the power supply control means for the sensor in the image forming apparatus, the power supply can be stopped when it is not necessary to operate the sensor.

In addition to controlling the power supply to the sensor,
A sensor failure can be detected and notified.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1 is a sectional view showing the structure of an image forming apparatus to which the present invention is applied. Here, the case of a laser beam printer is shown.

The configuration and operation of FIG. 1 will be described below.

The laser beam printer body 1 has a cassette 2 for accommodating the recording paper S, and the recording paper S of the cassette 2
Cassette paper presence sensor 3 and cassette 2 for detecting the presence / absence of paper
A cassette size sensor 4 for detecting the size of the recording paper S and a paper feed roller 5 for feeding the recording paper S from the cassette 2 are provided.

The recording paper S is provided downstream of the paper feed roller 5.
A pair of registration rollers 6 that synchronously convey the paper are arranged.
An image forming unit 8 that forms a toner image on the recording paper S based on the laser light from the laser scanner unit 7 is disposed downstream of the registration roller pair 6.

Further, a fixing device 9 for thermally fixing the toner image formed on the recording paper S is arranged downstream of the image forming portion 8, and downstream of the fixing device 9 the paper of the paper discharging portion is provided. A paper ejection sensor 10 for detecting the conveyance state, a paper ejection roller 11 for ejecting the recording paper S, and a stacking tray 12 for stacking the recording paper S for which recording has been completed are arranged.

The laser scanner section 7 includes a laser unit 13 which emits a laser beam modulated based on an image signal sent from an external device, and a photosensitive drum 1 which will be described later with the laser beam emitted from the laser unit 13.
It is composed of a polygon motor 14 for scanning on 7, a focusing lens group 15, a folding mirror 16 and the like.
The image forming section 8 includes a photosensitive drum 17, a pre-exposure lamp 18, a primary charger 19, a developing device 20, a transfer charger 21, and a cleaner 22 having a cleaner blade 22a, which are necessary for a known electrophotographic process. Has been done.

The main motor 23 applies a driving force to the paper feed roller 5 via a paper feed roller clutch 24 and to the registration roller pair 6 via a registration roller clutch 25. Driving force is also applied to each unit fixing device 9 and the paper discharge roller 11 of the image forming unit 8 including the above.

A control unit 30 controls the main body 1, and is connected to an external device.

Inside the control unit 30, a sensor power supply unit 33 for supplying power to the cassette paper presence sensor 3 and the paper discharge sensor 10, a power supply control unit 32 for turning on / off the sensor power supply, a power supply control unit 32, and A CPU 31 that controls the sequence of the main body 1 is provided.

Next, the relationship between the CPU and the input / output elements will be described with reference to FIG.

As shown in FIG. 2, the CPU 31 inside the control unit 30 is connected to the power supply control unit 32 through the OUTPUT port of the I / O, and outputs the High level signal to supply power to the sensor. The sensor can be powered by stopping and outputting a low level signal.

From the power supply controller 32, ON / O
An FF controllable power supply line is connected to the sensor power supply unit 33. The sensor power supply unit 33 distributes the power supply to the cassette paper presence sensor 3 and the paper discharge sensor 10.

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

Start (101): CPU 31 is Low
Is output and the power supply to the sensor is turned on (102).
After that, initial preparation is performed so that the main body 1 can print (103). The CPU 31 outputs a High signal,
The power supply to the sensor is turned off (104). This is the main body 1
Becomes a printable standby state (105).

Here, the process waits for a print signal from the external device (106). When the print signal is received from the external device, the power supply to the sensor is restarted (107) and the printing operation is performed (108). When printing is completed, turn on the power to the sensor.
FF is performed (109), and a standby state is set (105).

Next, the effect peculiar to the first embodiment will be described.

In this type of image forming apparatus, generally, of the energizing time, the time waiting for the print signal in the standby state is long. Therefore, by turning off the power supply to the sensor during the standby state, a very large power saving effect can be expected.

Second Embodiment FIG. 4 is a block diagram showing a second embodiment. This embodiment is different from the first embodiment in the sensor connection method.

That is, in the second embodiment, the cassette paper presence sensor 3 and the paper discharge sensor 10 are connected in series to control the power supply.

As a peculiar effect of the second embodiment, there is an advantage that a required current can be reduced and a transistor used in the power feeding control section 32 can be downsized.

Third Embodiment FIG. 5 is a flowchart showing the operation of the third embodiment.
The configuration of the third embodiment and the connection with the CPU are the same as those of the first embodiment.

Start (111): The CPU 31 first turns on the sensor power supply (112) and inputs the sensor state (113). Next, after turning off the sensor power supply (114), the sequence is controlled (115).

When it is necessary to input the sensor state in the sequence control, the sensor power supply is turned on again (112),
Input the sensor status (113) and turn off the sensor power supply.
After (114), the sequence control is continued.

As will be described below, the unique effect of the third embodiment is that the power supply to the sensor is stopped except when the sensor state input is required, so that the sensor can be used with minimum power. It is in.

Fourth Embodiment FIG. 6 is a flow chart showing the operation in the fourth embodiment. The configuration of the fourth embodiment and the connection with the CPU are the same as those of the first embodiment.

The contents of the steps 121 to 130 shown in FIG. 6 are almost the same as the steps 101 to 109 of the first embodiment, and the failure diagnosis (12) is performed immediately before the standby (126).
5) is carried out.

The internal flow chart of the fault diagnosis (125) is shown in steps (131) to (143).

Fault diagnosis start (131): First, the fault flag is turned off (132). Next, the power supply to the sensor is turned on (133). If the sensor is operating normally, the sensor output is turned on when the power is turned on.

Therefore, if the output of the cassette paper presence sensor 3 is ON, it is normal (134), and if it is OFF, the failure flag is ON (137). The paper discharge sensor 10 also makes a similar determination (136, 137).

Next, the power supply is turned off (138). If the sensor is operating normally, the sensor output is turned off.
Therefore, if the output of the cassette paper presence sensor 3 is OFF, it is normal (139), and if it is OFF, the failure flag is turned ON (140). The paper discharge sensor 10 also makes a similar determination (1
41, 142).

Thus, the failure diagnosis is completed (14
3).

As a unique effect of the fourth embodiment, it is possible to diagnose the failure of the sensor.

[0045]

As described above, according to the present invention, since the power supply to the sensor can be controlled by having the state detection means (sensor) and the power supply control means to the sensor, the following effects can be obtained. To be

(1) When it is not necessary to operate the sensor, power supply to the sensor can be stopped to save power.

(2) A sensor failure can be detected and correct information regarding the failure can be provided to the operator.

[Brief description of drawings]

FIG. 1 is a sectional view illustrating a configuration of an image forming apparatus to which the present invention is applied.

FIG. 2 is a block diagram illustrating the electrical connection of FIG.

FIG. 3 is a flowchart showing power supply control of a sensor.

FIG. 4 is a block diagram illustrating electrical connection of the second embodiment.

FIG. 5 is a flowchart showing power supply control of a sensor according to the third embodiment.

FIG. 6 is a flowchart showing power supply control of a sensor according to a fourth embodiment.

[Explanation of symbols]

 1 Main Body 2 Cassette 3 Paper Presence Sensor 4 Cassette Size Sensor 5 Paper Feed Roller 6 Registration Roller 7 Laser Scanner 8 Image Forming Section 9 Fixing Device 10 Paper Ejection Sensor 11 Paper Ejection Roller 12 Loading Tray 13 Laser Unit 14 Polygon Motor 15 Imaging Lens Group 16 Folding mirror 17 Photosensitive drum 18 Pre-exposure lamp 19 Primary charger 20 Developer 21 Transfer charger 22 Cleaner 23 Main motor 24 Paper feed clutch 25 Registration roller clutch 30 Control section 31 CPU 32 Power supply control section 33 Sensor power supply section

Claims (2)

[Claims] 1. An image forming apparatus for forming an image on a recording medium on the basis of input image information, and a state detecting unit for detecting an internal state of the image forming apparatus, and power supply to the state detecting unit. An image forming apparatus comprising: a power supply control unit. 2. A sensor that detects an internal state of an image forming apparatus that forms an image on a recording medium, a power supply control unit that controls power supply to the sensor, and a failure detection unit that detects a failure of the sensor. A power supply control device for an onboard sensor, characterized in that power supply to the sensor is stopped as needed and that when the sensor fails, the fact is notified.