JPS61289338A - Discriminating device for original size - Google Patents

Abstract

PURPOSE:To prevent previously a miscopy from being made by specifying the arrangement of sensors for original detection. CONSTITUTION:The 1st photosensor 12 is arranged where it detects respective lengthwise one-end parts d(reference corner part) of originals of various sizes when they are set as specified. The 2nd - the 5th photosensors 13-16 are arranged where they detect respective lengthwise other-end parts when originals of B5-A3 are set as specified. Further, the 2nd - the 5th photosensors 13-16 are arranged where none of them detect the longitudinal-lateral inverted setting of an original of A4 when it is set as mentioned above.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to a lid for determining document size in a copying machine.

``Prior Art'' Copying machines are generally equipped with yi number of copy paper feeding devices, and by pressing a copy paper selection button on an operation panel, copies are made on copy paper of a desired size. There is.

However, in such a copying machine, if the user forgets to press the copy paper selection button or presses the copy paper selection button incorrectly, the size of the copy paper will be different from the desired size, resulting in a copying error. The same applies when copying is performed without copying paper of the desired size set in the copying machine.

Therefore, some conventional copying machines are equipped with an original size determination device that determines the size of the original placed on the platen glass and automatically selects the copy paper size based on this. be.

FIG. 7 shows an example of such a conventional document size discriminating device (see Japanese Patent Laid-Open No. 137539/1983). In this document size discrimination device, transmission type optical sensors 2 to 5 are arranged at four predetermined locations on one predetermined side of a platen glass 1, respectively. In this device, by performing logical operations based on the detection signals of four optical sensors 2 to 5, the original set on the platen glass 1 can be divided into A3 size,
It is designed to determine which size it is among four sizes: 84 size, A4 size, and 85 size.

``Problems to be solved by the invention'' By the way, in such a document size discrimination device, for example, 8
If a 5-size original is set as expected as shown in FIG. 7, only the optical sensor 2 will be shielded from light.
For example, as shown in Figure 8, if the set is misaligned to a certain extent or if the vertical and horizontal directions are reversed, the 2
The two optical sensors 2.3 are shielded from light. In such a case, even though the size of the original is 85,
It is determined that the size is 4, and copying is performed on A4 size copy paper. For example, as shown in FIG.
Place two 85-size originals side by side in the setting range for 85-size originals and place 84
Copying may be performed on sized copy paper, but in such a case, if the original is set only on the left side in the figure, 85 sized copy paper will be selected as the copy paper.

In view of these circumstances, it is an object of the present invention to provide a document size discriminating device that makes it impossible to determine the size of a document when it is set in a setting mode other than the intended setting mode. is its purpose.

"Means for Solving the Problem" The present invention includes the same number of document detection sensors as the size of the document to be determined, and a determining means for determining the document size based on the detection signals of these sensors. The sensor for detecting the original is one that corresponds to the setting range of large-sized originals within each setting range when each original is set as expected with the corner as the reference and the vertical and horizontal directions in the same direction. A document one size smaller than that size is placed outside the setting range, and a document half the size of the maximum size that can be determined is placed with the corner as the reference and the orientation is reversed with respect to the intended setting mode. It is arranged so that it is placed outside the set range when it is set.

According to the present invention, for example, when an 85-size original is set with the aspect and width reversed, or when only one sheet of 85-size originals is placed side by side and copied, the size is determined. Can not do it. Therefore, in such a case, it is possible to prevent copying from being performed even if the copy start button is pressed.

Furthermore, if the determination means is configured to perform the document size determination operation when a corner detection sensor placed at a reference corner of the document setting range detects the reference corner of the document, the document may be misaligned to some extent. When set, the size can be prevented from being determined.

Note that if it is desired to make a copy with the original set in a setting manner other than the intended setting manner, the size of the copy paper may be selected independently of the original size determination device according to the present invention.

"Example" The present invention will be described in detail below with reference to Examples.

FIG. 1 shows the main parts of the document size discrimination device of this embodiment. This document size determination device is capable of determining the size of a document when it is set on the platen glass 11 with the corner as a reference. For this purpose, reflective or transmissive optical sensors 12-
16 are arranged respectively. Among these, the first optical sensor 12 is located at a position where it can detect each end (reference corner) in the length direction when a document of each size is set as expected as shown in FIG. It is located in The second to fifth optical sensors 13 to 16 each have B5 size to A
It is arranged at a position where each other end in the length direction can be detected when a 3-size original is reset as expected. Further, the second to fifth optical sensors 13 to 16 are
As shown in FIG. 2, when an A4 size document is set with its length and width reversed, it is placed in a position where it cannot be detected.

FIG. 3 shows the main part of the electric circuit of this document size discriminating device. This device is a CPU (central processing unit)
21, and is connected to each part through a path line 22 such as a data bus. Among these, a ROM (read only memory) 23 is a memory in which a program for controlling the circuit is written. A RAM (random access memory) 24 temporarily stores processing data for determining the document size and other processing data. The sensor manual port 25 is connected to the first to fifth optical sensors 1
This is a circuit portion that manually processes the data output from Nos. 2 to 16 and sends it onto the pass line 22.

Next, there is a flowchart of the operation of this document size discrimination device (Figure 4).
I will explain it together. The CPU 21 has the first to fifth optical sensors 1
Determine whether 2 to 16 are on or off in order (steps ■ to ■
). Whether the first to fifth optical sensors 12 to 16 are turned on or off depends on the size and setting manner of the document set on the platen glass 11. If the document 41 is not set on the platen glass 1, or if it is deviated from the reference corner to some extent even if it is set on the platen glass, the first
The optical sensor 12 of is in the off state (step ■; N)
. Therefore, in this case, the CPLI 21 does not perform the document size determination operation.

On the other hand, when an 85-sized to A3-sized original is set on the platen glass 11 as shown in FIG. 1, the first to fifth optical sensors 12 to 16 are turned on and Off is as shown in the table below. In this table, the ○ mark represents the on state, and the X mark represents the off state (the same applies hereinafter).

Table 1 below: The first and second optical sensors 12.13 are both on (steps ■, ■; Y), and the third to fifth optical sensors 14 to 16 are both off (steps ■ to ■; N) In this case, the CPU 21 determines that the size of the original set on the platen glass 11 is 8.
It is determined that the size is 5 (step ■). When the first to third optical sensors 12 to 14 are both on (steps ■ to ■; Y) and the fourth and fifth optical sensors 15, 16 are both off (steps ■, ■: N), The CPU 21 determines that the size of the document is A4 (step ■).

The first to fourth optical sensors 12 to 15 are both on (steps ■ to ■; Y), and the fifth optical sensor 16 is off (step
;N), the CPU 21 determines that the size of the document is 84 format (step ■). If the first to fifth optical sensors 12 to 16 are all on (steps 2 to 2; Y), the CPU 21 determines that the size of the document is A3 (step 2).

On the other hand, when each 85-size or A4-size original is set with the orientation reversed as shown in Fig. 2, the on/off status of the first to fifth optical sensors 12 to 16 is as shown in the table below. It becomes as shown in .

Table 2 In this case, only the first optical sensor 12 is turned on, so the CPU 21 cannot determine the size of the document. Therefore, in this case, the CPU 21 has the platen at the last position.
It is determined that the original is not set as expected on 1.
Even if the copy start button is pressed, the copying operation is not started, and erroneous copying is prevented.

On the other hand, if two 85-size or A4-size originals are set side by side in the setting range of 84-size or A3-size originals, the first to fifth optical sensors 12 to 160
On and off are shown in the table below.

Table 3 As is clear from Table 3, when two 85-size originals are set side by side, the CPU 21 determines that the size of the original is 84, and in the case of an A4-size original, It is determined that the size of the original is A3. Therefore, in this case, when the copy start button is pressed, copies will be made on 84-size or A3-size copy paper.

By the way, many recent copying machines are equipped with a reduction/enlargement function. In such a copying machine, for example, the reduction ratio is 115% (
85 size or 84 size to A4 size or A3 size) and an 85 size original is set on the platen glass 11, the A4 size original is set as copy paper based on the reduction ratio of 115%. can also be selected.

Furthermore, in order to improve the efficiency of office work, recent copying machines automatically feed the original placed in the original setting section next to the platen glass onto the platen glass, and send it out after copying is complete. Some are equipped with a document transport device. The present invention can also be applied to such a copying machine. In this case, the size of the document may be detected by the document setting section of the document conveyance device.

FIGS. 5 and 6 show an example of a copying machine equipped with such a document conveying device. With this copier,
A platen glass 32 is provided at the center of the upper part of the main body 31, a document setting section 33 is provided on the right side of the platen glass 32, and a document ejection section 3 is provided on the left side of the platen glass 32.
4 are provided respectively. A platen cover 35 is provided above the platen glass 32 so as to be openable and closable around its rear end.

Five reflective optical sensors 36 to 40 are provided at the right end of the platen cover 35. The optical sensors 36 to 40 are arranged in the same position as described in FIGS. 1 and 2 with respect to the original 41 set in the original setting section 33 as expected.

Inside the platen cover 35, a carry-out roller 42 and a carry-in roller 43 are rotatably provided at predetermined positions on the left and right sides of the platen cover 35, respectively. The unloading roller 42 uses the same driving force (
The signal is transmitted via a universal joint (not shown) and rotated in the direction of the arrow.

A belt 44 is wound around two rollers 42 and 43. A box 45 is provided inside the belt 44. A plurality of slits 46 are provided at intervals on the lower surface of the box 45.

A large number of small holes (not shown) are provided at predetermined locations on the belt 44 at intervals corresponding to these slits 46.

The inside of the box 45 is connected to a blower, also not shown, via a tube, not shown.

Resist gates 48 and 49 are provided on the right and left sides of the platen glass 32, respectively, so as to be rotatable about horizontal axes (not shown). These resist gates 48
．． 49 is normally protruded appropriately above the platen glass 32, and is rotated to be positioned below the surface of the platen glass 32 when a silent plunger solenoid is driven.

A feed roller 51 is rotatably provided at a predetermined location within the platen cover 35 to the right of the right registration gate 48 . The feed roller 51 is connected to the platen cover 3
When driven by a motor (not shown) provided inside 5, it is rotated in the direction of the arrow. A pinch roller 52 is provided below the feed roller 51 so as to be able to move vertically.

The pinch roller 52 is normally at the lower limit position, but when a plunger solenoid (not shown) is driven, the pinch roller 52 is moved upward and brought into contact with the feed roller 47.

A discharge roller 53 is rotatably provided at a predetermined location within the platen cover 35 to the left of the left registration gate 49 . The discharge roller 53 is the discharge roller 43
The rotational force is transmitted through a transmission mechanism (not shown), and the rotational force is rotated in the direction of the arrow. Also, the discharge roller 5
3 is adapted to come into contact with a triangular jump base 54 provided on the copying machine main body 31 when the platen cover 35 is closed.

Let us now assume that the platen cover 35 of this copying machine is closed, and in this state, the original 41 is automatically fed and copied. In this case, first, the document 41 is set in the document setting section 33 as expected, and its leading edge is brought into contact with the registration gate 48 .

Then, as described above, the size of the original document 41 is determined based on the detection signals from the five optical sensors 36 to 40, and the size of the copy paper is selected.

When a copy start button (not shown) is pressed in this state, the registration gate 48 is first moved down to release the original 41 from being locked. Further, as the feed roller 51 begins to rotate, the pinch roller 52 is moved upward and comes into contact with it. As a result, the original 41 is sent out from the original setting section 33, and the leading edge of the original 41 is appropriately inserted between the belt 44 and the platen glass 32. The document 41 that entered the belt 4
The box 45 is transported by traveling in the direction of the arrow 4.
The position corresponding to the slit 46 is reached. At this time, the inside of the box 45, together with the slit 46 and the corresponding small hole of the belt 44, is brought to a negative pressure by the blower. Therefore, the original 41 is attracted to the surface of the belt 44 and conveyed.

When the leading end of the original 141 reaches a position slightly before the registration gate 49, a sensor (not shown) detects this, and the motor for driving the belt is stopped. Then, the belt 44 travels a little due to inertia and then stops, and the leading edge of the document 41 is latched to the registration gate 49 as expected. As a result, the manuscript 41
has been set at the desired copying position on the platen glass 11. After that, copying is started at a predetermined timing, and the specified number of copies are made.

When the specified number of copies have been completed, the registration gate 49 is moved down at this timing to release the original 41 from being locked. After this, the belt 44 runs again in the direction of the arrow, and the discharge roller 53 begins to rotate again.
The original 41 is ejected to the original ejection section 34 via the jump table 54.

When the specified number of copies have been completed, the next manuscript 41
is set in the document setting section 33, and the optical sensors 36 to 40
If the size of the original document 41 has been detected by the belt 44, the previous document 41 is ejected by running the belt 44, and at the same time, the next document 41 is fed. If the original 41 is not set in the original setting part 33 even after a certain period of time has elapsed since the original 41 was delivered to the original discharge part 34, the copying machine enters the stop mode.

By the way, when, for example, two 85-size originals 41 are set side by side in the setting range of 84-size originals in the original setting section 33 of this copying machine, the process described above is based on the detection signals of the five optical sensors 36 to 40. As described above, the size of the set original is determined to be 84 size, and 84 size paper is selected as the copy paper when copying at the same size. On the other hand, when only one 85-size original 41 is set in the original setting section 33 with the aspect and width reversed, the original 41
1 size cannot be determined. Therefore, in this case, as described above, even if the copy start button is pressed, the copying operation is not started, and erroneous copying is prevented.

In the document conveyance device of this copying machine, a document 41 is conveyed by a belt 44 equipped with an air suction mechanism.

For this reason, for example, if two pairs of 85-size originals 41 are set side by side in the original setting range of the original setting section 33084, and these are fed onto the platen glass 32 at the same time, slipping may occur between the belt 44 and the originals 41. do not have. Therefore, the two original documents 41 are sent as they are to the desired copying position on the platen glass 11 without overlapping each other.

In contrast, in conventional document conveying devices, documents are conveyed only using a belt. Therefore, slipping may occur between the belt and the document, and when two documents are conveyed at the same time, they may overlap each other. Further, in many of these document conveying devices, the document is slightly skewed in a predetermined direction in order to better feed the document to a desired copying position on the platen glass with reference to a corner. In such a device, when two originals are conveyed at the same time, they almost overlap. In any case, with conventional document conveying devices, when two documents are conveyed at the same time, they may overlap each other.
There was a problem with unreliable document transport.

Incidentally, an apparatus has previously been proposed that can efficiently feed a plurality of sheets onto the platen glass of a copying machine at the same time using a belt (see Japanese Patent Application Laid-open No. 163529/1983). However, this proposed device is not suitable for conveying original documents because each card is conveyed by being held by a large number of locking plates provided on the outer surface of the belt. In addition, the card must be locked to and removed from the locking plate, and a mechanism for this is required, making the device complicated.

``Effects of the Invention'' As explained above, according to the present invention, for example, an 85-size original may be set with the aspect reversed, or when two 85-size originals are placed side by side for copying, only one sheet may be set. If the size of the original cannot be determined, the size of the original cannot be determined. Therefore, if copying is not performed even if the copy start button is pressed in such a case, it is possible to prevent erroneous copying.

Furthermore, if the size of the original is not determined when the original is set with a certain degree of misalignment, it is possible to prevent copy errors from occurring.

[Brief explanation of drawings]

Figures 1 to 4 are for explaining one embodiment of the present invention, of which Figures 1 and 2 are plan views showing the arrangement of optical sensors, and Figure 3 is a schematic diagram of the electrical circuit. FIG. 4 is a flowchart showing the operation of determining the size of the original.
Fig. 5 is a schematic front view showing the main parts of a copying machine to which the present invention is applied, Fig. 6 is a schematic plan view of a part of the copying machine, and Fig. 7 is the arrangement of optical sensors in a conventional document size determination device. FIGS. 8 and 9 are plan views showing the relationship and are shown to explain the drawbacks of the device. 11.32...Platen glass, 12-16.
36-40... optical sensor, 21... c
pu. 23...ROM. 24...RAM. 25...Sensor manual boat, 33...Document setting section, 34...Document discharge section, 41...Document, 44...Belt , 45...box. Applicant Fuji Xerox Co., Ltd.

Claims (1)

[Scope of Claims] 1. A sensor for detecting the document, comprising the same number of document detection sensors as the size of the document to be determined, and a determining means for determining the size of the document based on detection signals from these sensors; is one size smaller than the one corresponding to the setting range of the larger size original within each setting range when each original is set as expected with the corner as the reference and the vertical and horizontal directions are the same. When a document of a size that is placed outside the setting range of the original size and is half the size of the maximum size that can be determined is set with the corner as the reference and the orientation is reversed with respect to the intended setting mode. A document size determining device characterized in that it is arranged outside a setting range. 2. The determining means performs an operation of determining the document size when a corner detection sensor disposed at a reference corner of the document setting range detects a reference corner of the document. The document size determination device according to item 1.