JP2624766B2 - Document size detection method - Google Patents

Description

The present invention relates to a method for detecting the size of a document to be copied,
In particular, the present invention relates to a method for detecting the size of a document using a plurality of document sensors.

[Prior Art] Conventionally, when detecting the size of a document to be copied, an
As shown in the drawing, a method of detecting a size using a plurality of document sensors 100, 101, 102, and 103 for detecting the presence of a document is known (for example, Japanese Patent Application Laid-Open No. 62-6242). .
In this case, the detection of the document size is started, for example, by the document sensor 100 that can detect even the smallest B5 size document 104.
When the original 104 is detected, the other original sensors 101, 102, 1
The detection of the size of the original placed together with 03 starts.

[Problems to be Solved by the Invention] However, as described above, when a document is detected by one specific document sensor 100, as shown in FIG. When the partial document 105 having the size is placed at the position shown in the drawing and is to be copied, the document sensor 100 cannot detect the presence of the partial document 105, and thus does not start detecting the document size forever.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described problems with the conventional document size detection method, and has as its object to provide a method that can detect a document size even for a partial document.

[Means and Actions for Solving the Problems] According to the first aspect of the present invention, outputs from a plurality of document sensors for detecting the presence of a document, which are movably arranged between a home position and a predetermined position. In a document size detecting method for detecting the size of a document placed on a document table based on a signal, when the plurality of document sensors are at the home position, the presence or absence of a document is detected using the document sensors. From the detection results, (a) when at least one of the document sensors detects the presence of the document, or (b) when neither of the document sensors detects the document, If it is detected that the cover has been closed, it is determined that the document has been positioned on the platen. If the determination result is obtained, the movement of the plurality of document sensors is opened. First, a document size detection method for detecting the size of a document using a detection result of the presence or absence of a document obtained when the document sensor is moved.

EXAMPLES Hereinafter, the present invention will be described with reference to the drawings showing examples.

First, an example of a document size detecting device used when carrying out the document size detecting method according to the present invention will be described.

FIG. 1 is a schematic vertical sectional view of the document size detecting device. FIG. 2 is a schematic plan view of the same device. FIG. 3 is a schematic vertical sectional view centering on a document pressing cover of the apparatus.

An exposure lamp 3 is provided inside the housing 23 of the copying machine main body.
And the first moving frame 1 holding the first reflecting mirror 2, the second moving frame 5 holding the second and third reflecting mirrors 4, 4, and the document sensors 11, 12, 13, and 14 at appropriate positions. The built-in sensor support frame 15 is provided. Document sensors 11, 12, 13, 14
Includes an LED light emitting element for emitting light, and a phototransistor for receiving the light reflected by the document and converting the light to an electric signal. Wire 18 is driving means
By means of 181, it moves via guide pulleys 19, 19, and one end of the first moving frame 1 is fixed.
The wire 18 is wound around a pulley 20, moves the pulley 20, and moves the second moving frame 5 fixed to the pulley 20.

On the other hand, the wire 16 is moved by the driving means 161 via the guide pulleys 17, 17, and one end of the sensor support 15 is fixed. Therefore, the sensor support frame 15
Is moved by a wire 16. The guide rails 21 and 22 are guide rails for smoothly guiding the first moving frame 1, the second moving frame 5, and the sensor support frame 15 in the vertical direction (moving frame moving direction).

In FIG. 1, two-dot chain lines indicate those first moving frames 1,
This shows a state where the second moving frame 5 and the sensor support frame 15 have moved. In FIG. 2, two-dot chain lines indicate A4 and B5 on the platen 26.
Indicates the reference area where the original should be placed. The lens 27 in FIG. 1 is a lens that condenses the light reflected from the second and third reflection mirrors 4, and the fourth reflection mirror 6 reflects the light condensed by the lens 27 and irradiates the photosensitive drum 7. Reflecting mirror. Around the photosensitive drum 7, a developing device 10, a paper feed roller 9, a transfer electrode 8, and the like are arranged.

In FIG. 3, reference numeral 24 denotes a document pressing cover. A cover sensor such as a limit switch that detects an operation of closing the document holding cover 24 is provided immediately below the lower end thereof.
25 are arranged. In order for the cover sensor 25 to detect the closing operation of the document holding cover 24 as soon as possible,
The probe 251 extends upward.

FIG. 4 is a block diagram of a control unit using a microcomputer of the document size detecting device.

In the figure, the original sensors 11, 12, 13, and 14 are connected to a bus 29 via an input interface 27. The bus 29 is connected to a ram (RAM) memory 30 for storing a document size flag and the like to be described later, and a rom (ROM) memory 31 for storing a program for performing control. Further, an operation panel 33 for displaying the detected document size is connected to the bus 29 via the output interface 32. 28 is a central processing unit (CPU). Three
5 is a timer.

Next, the document size detecting method according to the present invention will be described with reference to the flowchart of FIG. An example of a document size detection method of detecting a document size when the document holding cover 24 is open will be described.

First, the operator turns on the main power supply of the copying machine and opens the document holding cover 24. As a result, the CPU 28 resets and initializes the document size flags such as the A3 and B4 flags used later in the ram memory 30 (step S1). The original sensors 11, 12, 13, and 14 start detecting the original.
At first, there is no original, so the original sensors 11, 12,
Documents 13 and 14 do not detect any document (step S2). or,
Since this is the first time, the operator does not close the document holding cover 24 yet (step S3).

Then, the operator places the original to be copied on the original platen 26. When an original of a fixed size such as B5 or A4 is placed at a regular position, at least the original sensor 14 always detects the presence of the original and outputs a signal to the CPU 28 (see FIG. 8). S2). Also small partial manuscript
When the document 34 is placed on the document table 26 at a position as shown in FIG. 8, both the document sensors 13 and 14 detect the presence of the document 34 and output a signal to the CPU 28 (step S2). Next, using the timer 35, the CPU 28 determines whether or not the outputs of the document sensors 13 and 14 do not change for a predetermined time, for example, one second (steps S4 and S5). If it has changed, it is determined that the operator has not yet determined the copy position of the original document, and the process returns to the original position (step S5). The predetermined time can be appropriately determined in consideration of the editing operation of the original on the original platen by the operator.

On the other hand, even if none of the document sensors 11, 12, 13, and 14 detects the document at all, if the document holding cover 24 starts to close (step S3), the cover sensor 25 detects the closing operation and the CPU 28 Let it know. In that case, C
PU 28 determines that the operator intends to place and copy the partial document 34 at the position shown in FIG.

As described above, when the output of the document sensors 11, 12, 13, and 14 does not change, or when the document pressing cover S3 starts closing, the wire
The rotation of 16 causes the sensor support frame 15 to move in the vertical direction (paper feeding direction) as shown in FIG. Accordingly,
Outputs from the document sensors 11, 12, 13, and 14 change.

Based on the output signals of the original sensors 11, 12, 13, and 14, the original size is detected as follows (steps S6 and S7).

FIG. 10 shows the document table 26 divided into areas corresponding to the respective document areas of the document table 26.

Now, as shown in FIG.
Is present in the area A (step S15), when the sensor 11 detects reflected light (HIGH) (step S16), the A3 flag is set (step S20), and when the sensor 12 detects reflected light (HIGH) ( (Step S17), the B4 flag is set (Step S21), and when the sensor 13 detects the reflected light (H
IGH) (step S18), set the A4 flag (step
(S22) When the sensor 14 detects the reflected light (HIGH) (step S19), the B5 flag is set (step S23).

Further, as shown in FIG.
Is present in the area B (step S24), the sensor 11
Detects the reflected light (step S25), sets the A3 flag (step S29), and when the sensor 12 detects the reflected light (step S26), sets the B4 flag (step S3).
0), when the sensor 13 detects the reflected light (step S27),
The A4 flag is set (step S31), and when the sensor 14 detects the reflected light (step S28), the A4 flag is set (step S32).

Further, as shown in FIG.
Is present in the C area (step S33), the sensor 11
Detects the reflected light (step S34), sets the A3 flag (step S38), and when the sensor 12 detects the reflected light (step S35), sets the B4 flag (step S3).
9) When the sensor 13 detects the reflected light (step S36),
The B4 flag is set (step S40), and when the sensor 14 detects the reflected light (step S37), the B4 flag is set (step S41).

Further, as shown in FIG.
Is present in the D area (step S42), the sensor 11
When the sensor detects reflected light (step S43), it sets the A3 flag (step S47). When the sensor 12 detects reflected light (step S44), it sets the A3 flag (step S4).
8) When the sensor 13 detects the reflected light (step S45),
The A3 flag is set (step S49), and when the sensor 14 detects the reflected light (step S46), the A3 flag is set (step S50).

For example, as shown in FIG.
26, the sensor support frame 15 is
If it is located at the position indicated by the dashed line in the area, the document sensor 14
Since the detection signal is output only from, the B5 flag is set. Then, when the sensor support frame 15 comes to the area B, a detection signal is output only from the document sensor 14, so that the A4 flag is set in steps 28 and 32. When the sensor supporting frame 15 is located in the area C or in the area D, none of the original sensors detects the original, and the flag is not set any more.

When the sensor support frame 15 has passed the area D, in step 51 (FIG. 7), the CPU 28 checks the setting state of each flag and outputs the document size corresponding to the largest flag as the document size. In the above case, since A4 is larger than B5, the document size is determined to be A4.

The document size determined and detected in this manner is output to the operation panel 33 and displayed (step S8) (step S8).
Figure).

Thereafter, when the sensor support frame 15 reaches the movement end position (dotted line in FIG. 9) past the area D, the movement of the sensor support frame 15 is stopped (steps S9 and S10). Then, since copying becomes possible, the first and second moving frames 1 and 5 move to perform copying (step S11). When the document holding cover 24 is opened, it is considered that copying has been completed (step S12), and the sensor support frame 15 existing at the movement end position moves to the original home position and stops (steps S13 and S14).

As described above, while the partial document is being edited on the platen 26, the document size is displayed on the operation panel 33, so that the operator can know in real time how the copying machine judges the partial document. , Convenient. For example, the necessity of reduction / magnification can be known in advance, or it is easy to understand when a book of this type is poorly placed.

Note that by increasing the number of document sensors, the document size can be detected without moving the sensor support frame 15.

If none of the document sensors detects the presence of a document, the detection of the document size may not be started even if the document pressing cover 24 starts to be closed.

[Effects of the Invention] As is clear from the above description, the present invention
When at least one of the plurality of document sensors for detecting the presence of a document detects a document and / or when all document sensors do not detect a document and the document pressing cover performs a closing operation, Since the document size is detected, the document size can be reliably detected even if, for example, a cut-out partial document is placed on an arbitrary position on a document table.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a document size detecting device used in an embodiment of a document size detecting method according to the present invention, FIG. 2 is a plan view of the document size detecting device, and FIG. FIG. 4 is a block diagram of a control unit of the document size detecting device, FIG. 5 is a flowchart for explaining the operation of the document size detecting device, and FIG. FIG. 7 is another flowchart illustrating the operation of the document size detecting device, FIG. 7 is another flowchart illustrating the operation of the document size detecting device, FIG. 8 is a plan view of the document table of the document size detecting device, FIG. FIG. 10 is another plan view of the platen of the document size detection device, FIG. 10 is another plan view of the platen of the document size detection device, and FIG. 11 is a plan view of the platen of the conventional copying machine. FIG. 11, 12, 13, 14… Original sensor 15… Sensor support frame, 24… Original press cover 25… Cover sensor, 26… Original platen

Claims (1)

(57) [Claims] A size of a document placed on a document table is detected based on output signals from a plurality of document sensors for detecting the presence of a document, which are movably arranged between a home position and a predetermined position. In the document size detection method, when the plurality of document sensors are at the home position, the presence or absence of a document is detected using the document sensors, and based on the detection result, (a) at least one of the When the document sensor detects the presence of the document, or
(B) If none of the original sensors detects an original, and if it is detected that the original cover has been closed, it is determined that the original is positioned on the original platen. When the determination result is obtained, the movement of the plurality of document sensors is started, and the size of the document is detected by using the detection result of the presence or absence of the document obtained when the document sensors are moved. A document size detection method characterized by the following.