JPH10123878A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the side of original even before an image forming device is started by providing at least a means for supplying power to a detecting means for detecting the size of original independently of the supply of power by a power supplying means for supplying power to an image input means. SOLUTION: When an original is placed on a platen glass, reflective type sensors 5a-5c detect the presence of the original and a CPU 13 for the sensors recognizes the size of the original in accordance with the output. Further, the CPU 13 for the sensors stores the recognized size of the original in a memory 11 and displays the recognized size of the original in an original size display part 15. When a platen is closed at the time of reading an image by an image input part 10, a microswitch is turned on and the supply of the power is stopped by a control circuit 19 not to supply the power to a sensor part 18. At this time, the supply of the power to the original size display part 15 is switched from a second power supplying part 16 to a first power supplying part 17, so that the size of the original is continuously displayed.

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 for reading a document placed on a document table.

[0002]

2. Description of the Related Art A conventional image forming apparatus such as a copying machine has been commercialized which automatically detects the size of a document to be read. As the detection of the document size, there is known a method in which the size of a document placed on a document glass (platen glass) is detected by a plurality of reflection sensors disposed inside a copying machine main body below the document glass. .

FIG. 4 is a plan view of a document placing table of an image forming apparatus having such a document size detecting function as viewed from above.

As shown in FIG. 4, a reflection type sensor 5 (5a, 5a
b, 5c) are arranged below the platen glass 1.
Further, inside the sensor, there are provided a light emitting element (not shown) that emits infrared light and the like, and a light receiving element (not shown) that receives the reflected light of the infrared light emitted by the light emitting element reflected by an obstacle. I have.

When an obstacle (original) is placed on the platen glass 1, infrared light emitted from the light emitting element is reflected by the obstacle (original) on the platen glass 1 and is reflected. Infrared light is received by the light receiving element. When the light receiving element receives the reflected light, its output level becomes “L” level lower than the threshold value, and it is recognized that the document is placed on the sensor.

When the infrared light emitted by the light emitting element is not received by the light receiving element, the output level exceeds the threshold value, the output level becomes "H" level, and it is recognized that the original is not placed.

[0007] By combining the detection outputs of the reflection sensors 5a, 5b, and 5c, the original on the platen glass 1 corresponds to any one of the standard original sizes such as B5, A4, B4, and A3. Can be recognized.

[0008]

However, in the above-described image forming apparatus, even if an attempt is made to start reading a document image, the detection sensors are not energized when the main body is turned off. Even if the original is placed on the platen glass, the original size cannot be recognized, and the original must be recognized again when the power is turned on and the main unit starts up, leading to a large loss of time. I was

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and enables a user to detect a document size even before starting an image forming apparatus such as a copying machine, thereby shortening a work time. An object of the present invention is to provide an image forming apparatus which can execute a convenient and smooth operation for the user.

[0010]

According to a first aspect of the present invention, there is provided an image forming apparatus, comprising: a mounting table for mounting an original; a pressing unit for pressing the original mounted on the mounting table; Detecting means for detecting the size of the document when the document is not pressed by a pressing unit; image input means for reading an image of the document pressed by the pressing unit; and supplying power to at least the image input means. A first power supply unit for supplying power and a second power supply unit for supplying power to the detection unit independently of the supply of power by the first power supply unit are provided.

According to the image forming apparatus of the present invention, the second power supply means supplies power to the detection means when the document is not pressed by the pressing portion. When the document is pressed by the pressing unit, the second power supply unit includes a first control unit that controls so as not to supply power to the detection unit.

According to a third aspect of the present invention, there is provided the image forming apparatus according to the first or second aspect, wherein the image output means for outputting an image input by the image input means to a recording sheet; Selecting means for selecting the size of the recording sheet based on the detection output.

According to a fourth aspect of the present invention, there is provided the image forming apparatus according to the third aspect, further comprising storage means for storing a size of the document detected by the detection means.

According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects,
The second power supply means is a battery.

According to a sixth aspect of the present invention, in the image forming apparatus according to the third aspect, there is provided a display unit for displaying a size of the document detected by the detecting unit.

According to the image forming apparatus of the present invention, when the supply of power to the display unit by the second power supply unit is interrupted, the first power supply is performed. And means for controlling the display means to supply power to the display means.

According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, the second control unit is configured to interrupt the supply of power to the display unit by the first power supply unit. Wherein the second power supply means controls to supply power to the display means.

[0018]

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

FIG. 1 is a block diagram showing the configuration of an image forming apparatus according to the present embodiment.

The reflection sensors 5 (5a, 5b, 5c) are arranged below the platen glass 1 as shown in FIG. 4, and detect the presence or absence of a document placed on the platen glass 1 above. The sensor 5 includes a light emitting element (not shown) that emits infrared light or the like and a light receiving element for detecting the presence or absence of infrared light emitted by the light emitting element.

The output of each sensor is supplied to a sensor CPU.
13, the sensor CPU 13 outputs the signals to the sensors 5a, 5b,
The size of the document is determined based on the output obtained from step 5c.

When the light emitted from the light emitting element is reflected by the original and the reflected light is received by the light receiving element, the output level of the reflective sensor 5 becomes lower than the threshold value. 'Output level. When there is no reflective object, that is, when no original is placed, the output level of the reflective sensor 5 (5a, 5b, 5c) exceeds the threshold value and outputs an "H" level.

The sensor CPU 13 determines the document size based on a combination of the outputs of the reflection type sensors 5. Table 1 shows the document size recognized for each combination of outputs of the reflective sensors 5 (5a, 5b, 5c).

[0024]

[Table 1]

A second power supply unit 16 serving as a second power supply unit supplies power to the sensor unit 18, the memory 11, and the document size display unit 15, respectively. And independent. The second power supply unit 16 may be configured by, for example, a battery. The micro switch 4 is turned ON / OFF according to the opening and closing of the pressure plate 3.
A signal is generated and supplied to the control circuit 19.

The control circuit 19 controls the O of the microswitch 4
The N / OFF signal is used to cut off the supply of electric power from the second electric power supply unit 16 to the sensor unit 18 as a detecting unit. This is a first control unit that shuts off the power supply when the pressure plate unit 3 is closed.

The CPU 7 for the main body issues control commands for the main body of the image forming apparatus, such as control of an image input section 10 for reading an image of a document and an image output section 12 for outputting the read image. Image input unit 10 as image input means
Reads an original placed on the platen glass 1 with a line sensor or the like and converts the original into an electric image signal. The image output unit 12 as an image output unit converts an image signal read by the image input unit 10 and records an image on a recording sheet having a size selected by the recording sheet selecting device 14.

The recording sheet selecting device 14 includes a sensor CP
This is a selection unit that selects a recording sheet based on the document size recognized by U13. If you want to output an image that is the same size as the image on the original, select a recording sheet that is the same size as the original.If you want to enlarge or reduce the image on the original, select a recording sheet size that matches the enlargement / reduction ratio. It is possible to choose.

The original size display unit 15 is a sensor CPU.
13 and the size of the recording sheet selected by the recording sheet selecting device 14,
This is display means for performing display for the user to confirm.
Although the power is normally supplied to the document size display unit 15 from the second power supply unit 16, the second power supply unit 1
When power is not supplied from the power supply 6, switching of power supply is controlled by the main body CPU 7 serving as second control means so as to supply power from the first power supply unit 17.

The memory 11 is storage means such as a semiconductor memory for storing the size of the document recognized by the sensor CPU 13, and updates the stored content every time the size of the document is recognized. The first power supply unit 17 supplies power to components other than the sensor unit 18.

Next, FIG. 2 is a side view of the vicinity of the document table, which will be described below with reference to this drawing.

A pressure plate portion 3 as a pressing portion is provided above the document table. This is to press the document when the image is read by the image input unit 10 so that the image on the document 2 can be read accurately. When the pressure plate portion 3 is closed, the microswitch 4 is turned on through the actuator arm 3a, the power supply is cut off by the control circuit 19 in FIG. 1, and the power is not supplied to the sensor 5. When the pressure plate 3 is opened, the micro switch is turned on.
It becomes FF and power is supplied to the sensor 5 again.

The platen glass 1 is a mounting table on which the original 2 is placed when an image on the original 2 is read by the image input unit 10 in FIG. 1, and the end of the original 2 is aligned with A in FIG. Place.

FIG. 3 is a flowchart for starting up the main body of the image forming apparatus according to the present embodiment. The operation from the start-up of the main body to the reading of the original will be described with reference to FIG.

First, when a document is placed on the platen glass 1 with its edge aligned with the position A (s1), the reflection sensors 5a, 5b, 5c detect the presence or absence of the document above each of them, and CPU1 for sensor according to the output of
3 recognizes the size of the document (s2). Further, the sensor CPU 13 stores the recognized document size in the memory 11, and causes the document size display unit 15 to display the size of the document recognized by the sensor (s3).

Next, it is confirmed whether or not the main body of the image forming apparatus, such as the image input unit 10 and the image output unit 12, has been started (s4). If not, the first power supply unit 17 has been started. Is turned on to supply power to the main body (s
5).

When the startup of the main body is completed (s
6) The CPU 7 for the main body causes the recording sheet selection device 14 to select a recording sheet suitable for the document size recognized by the sensor CPU 13 (s7).

When the image input unit 10 reads an image, when the pressure plate is closed (s8), the microswitch 4 is turned on through the actuator arm 3a, the power supply is cut off by the control circuit 19, and the power is supplied to the sensor unit 18. It is no longer supplied (s9). At this time, the power supply to the document size display unit 15 is switched from the second power supply unit 16 to the first power supply unit 17, so that the recognized document size is always displayed.

In this case, the procedure is such that the pressure plate 3 is closed after the start of the main body, but there is no problem if the pressure plate 3 is closed before the main body is started. At this time, even if the supply of power to the sensor unit 18 is cut off, the recognized document size is stored in the memory 11, so that information on the document size is called from the memory 11, and the recording sheet selecting device 14 performs optimal recording. The sheet is selected. With such a procedure, the working time is further reduced.

When the preparation for reading the image is completed, the image on the document is read by the image input unit 10 (s10), and the image output unit 12 reads the image on the recording sheet of the size selected by the recording sheet selecting device 14. Is output (s11).

As described above, since the size of the document is recognized before the power of the apparatus body rises, immediately after the apparatus body starts up, it is possible to execute reading of an image on the document and recording on a recording sheet. An image forming apparatus in which a user's work is greatly reduced can be provided.

[0042]

As described above, according to the image forming apparatus of the first aspect of the present invention, the size of the original can be detected by the sensor regardless of whether the power of the image input means is ON or OFF. For example, when starting up the apparatus main body, a time lag is small, and smooth reading can be performed. Also, before starting up the device, place the original on the
Even if the pressure plate is lowered, the size of the placed document has already been detected by the sensor, so that the image can be read at the same time when the apparatus is started up.

Further, according to the image forming apparatus of the present invention, the power supply time to the sensor can be greatly reduced, the power consumption can be suppressed, and the life of the sensor can be extended.

According to the image forming apparatus of the present invention, since the size of the recording sheet is selected based on the detection output of the sensor, it is possible to select an accurate sheet.

According to the image forming apparatus of the present invention, even when the power supply to the sensor is cut off, the size of the document recognized by the sensor is stored in the memory. Can be detected.

According to the image forming apparatus of the present invention, the power is supplied to the sensor section by the battery, so that the apparatus can be downsized.

Further, according to the image forming apparatus of the present invention, since the size of the document recognized by the sensor unit is displayed, it is necessary to confirm whether the sensor correctly detects the size of the document. Can be.

According to the image forming apparatus of the present invention, even if one of the first power supply unit and the second power supply unit is shut off, the original size stored in the memory can be reduced. Display can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram of an image forming apparatus according to the present invention.

FIG. 2 is a side view of the vicinity of a document table in the image forming apparatus of the present invention.

FIG. 3 is a flowchart for starting up the main body of the image forming apparatus of the present invention.

FIG. 4 is a top view of a document table of the image forming apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 platen glass 2 document 3 pressure plate 4 micro SW 5 sensor 7 main body CPU 10 image input unit 11 memory 12 image output unit 13 sensor CPU 14 recording sheet selection device 15 document size display unit 16 second power supply unit 17 first power Supply unit 18 Sensor unit 19 Control cycle

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 1/04 106 H04N 1/04 106A

Claims (7)

[Claims] 1. A mounting table on which an original is mounted, a pressing unit for pressing the original mounted on the mounting table, and detecting the size of the original when the pressing unit does not press the original. Detecting means; image input means for reading an image of a document pressed by the pressing portion; first power supply means for supplying power to at least the image input means; and power from the first power supply means An image forming apparatus comprising: a second power supply unit that supplies power to the detection unit independently of supply of the image data. 2. The apparatus according to claim 1, wherein the second power supply unit supplies power to the detection unit when the document is not pressed by the pressing unit, and the document is pressed by the pressing unit. The first power supply unit controls so that the second power supply unit does not supply power to the detection unit.
An image forming apparatus comprising: 3. The recording sheet according to claim 1, further comprising: an image output unit configured to output an image input by the image input unit to a recording sheet; An image forming apparatus comprising: a selection unit for selecting a size. 4. The image forming apparatus according to claim 3, further comprising storage means for storing a size of the document detected by said detection means. 5. The image forming apparatus according to claim 1, wherein the second power supply unit is a battery. 6. The image forming apparatus according to claim 3, further comprising display means for displaying a size of the document detected by said detection means. 7. A second control method according to claim 6, further comprising: selectively supplying power to said display means from one of said first power supply means and said second power supply means. An image forming apparatus comprising a control unit.