JPH02167536A - Picture reader - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a copying mistake and to improve operation convenience by automatically resetting the original size detecting data of the previous use in the case of changing an original under the condition that an original cover is opened less than the standard angle. CONSTITUTION:The subject reader is provided with an angle detector which detects whether the opening angle of the original cover 205 which opens/closes the upper side of an original platen glass 16 is more or less than the standard angle and sets the detecting performance of an original size detecting means when the angle is more than the standard angle, and an opening/closing detector which detects the opening/closing condition of the original cover 205. The storage contents of a memory is reset at the time when the original cover performs the opening operation. Thus, in the case of changing the original with the different sized original, the original size data of the previous use is reset, then, the original size detection of the object to be read is performed, and reading operation is performed based on the result. Thus, when the reading operation is performed under the condition that the original cover is opened at less than the standard angle, the copying mistake is hardly occurred.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image reading apparatus equipped with an original size detecting means for detecting the size of an original placed on an original table glass.

'No', Part 1 When reading a document image, it is necessary to detect the document size and image density in order to set the scanning range and light intensity of the optical system, and for this purpose, document size detection means and image density detection means are required. be equipped. This type of document size detection means and image density detection means detects the size and density of the document set on the document table glass each time a document image is read, and reports the detected data to the memory. Become. Then, a control device that controls the entire copying operation controls the scanning range and light amount of the optical system in accordance with the detection data stored in the memory.

Here, the document is placed on the document platen glass in automatic mode or manual mode. That is, for example, ADF
In a copying machine (image reading device) equipped with an automatic document feeder (automatic document feeder), copying is performed in an automatic mode in which the ADF automatically transports and sets the original placed on the document glass. Copying is performed in a manual mode in which the operator opens the document frame cover that covers the document table glass and sets the document on the document table glass.

In addition, in this type of copying machine, when opening the document frame cover, it is usually set at 30 mm for ease of use.
It is designed to be stopped at the opening angle position (reference angle) of °.

A problem with this type of copying machine is to prevent the following copying errors. That is, in such a copying machine, when the document frame cover is generally stopped at the above-mentioned open angle position, an angle detector detects this state and notifies the control device to replace the document in order to prevent malfunction. However, in this case, if you try to execute manual mode with the document frame cover open to less than 30 degrees, the angle detector will not operate and document switching information will not be input to the control device. Become. Therefore, the control device executes the copying operation based on the detection data regarding the previous document stored in the memory, resulting in a copying error.

In the past, there has been no image reading device equipped with means for solving this problem.

The present invention has been made to solve the problems of the prior art, and provides an image that does not cause copying errors even when the reading operation is performed with the document frame cover opened below the reference angle. The purpose is to provide a reading device.

The present invention is an image reading device equipped with a document size detecting means for detecting the size of a document set on a document table glass, wherein a memory device for storing the detection result of the means; and a memory device for detecting whether the opening angle of the document frame cover that opens and closes the upper surface side of the document platen glass is greater than or equal to a reference angle or less than a reference angle, and when the angle is greater than or equal to the reference angle, the document size is detected. an angle detector for setting the detection execution of the means, and an open/close detector for detecting the open/closed state of the document frame cover, and reset the memory contents of the memory device at the time when the document frame cover performs an opening operation. It is characterized by being configured to do so.

If the rice bowl is scolded, open the document frame cover below the standard angle.
When exchanging originals of different sizes, the original size data for the previous original is reset, then the original size of the original to be read is detected, and the reading operation is performed based on this detection result. become.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image reading device according to the present invention will be described below with reference to the accompanying drawings.

[Overall configuration and operation of copying machine]

FIG. 1 shows a copying machine to which the present invention is applied.
A photoreceptor drum 1 is rotatably supported approximately in the center of 00 in the direction of arrow a in the figure, and around it are eraser lamps 2. Electrostatic charger 3 Image edge/interimage eraser 4. A developing device W 6 , a transfer charger 7, a separation charger 8 and a cleaning device 9 are arranged in this order. The photoreceptor drum 1 has a photoreceptor layer provided on its surface, and this photoreceptor layer is uniformly charged by passing through the eraser lamp 2 and the charger 3, and then passed through the scanning optical system 10 through the slit section 5. Upon image exposure, an electrostatic latent image is formed on its surface. The image end/interimage eraser 4 has a plurality of light emitting diodes arranged in the image width direction, and removes unnecessary charges from the surface of the photoreceptor drum 1 during image formation.

The optical system 10 is installed below the document table glass 16 so as to be able to scan the document image, and includes an exposure lamp 17, movable mirrors 11, 12, 13, a lens 14, and a mirror 15. The exposure lamp 17 and the movable mirror 11
moves integrally in the direction indicated by the arrow at a speed of (V/m) (however, 9 m: copying magnification) with respect to the circumferential speed of the photosensitive drum 1 (constant regardless of whether the magnification is the same or variable magnification). , movable mirror 1
2.13 are driven by a scan motor M3 so as to move integrally in the direction indicated by the arrow at a speed of (V/2 m). In addition, when changing the copy magnification, use the stepping motor M.
4, the lens 14 moves on the optical axis and the mirror 15 moves and swings to correct the optical path.
Such a magnification changing mechanism is already known in principle.

Also, regarding control of the scanning speed of the optical system 10,
Control is performed to change the rotational speed of the scan motor M3 in accordance with the copy magnification data, but a detailed explanation of the control method and the like will be omitted.

Copy paper is fed into the machine by an automatic paper feeding mechanism 20 provided on the left side of the copying machine main body 100 in the figure and having upper and lower cassette loading sections, or by a manual paper feeding mechanism 30 provided above it. After being temporarily stopped by the roller pair 21, the toner image is sent to the transfer section in synchronization with the image formed on the surface of the photoreceptor drum 1, the toner image is transferred by the transfer charger 7, and the toner image is transferred to the photoreceptor drum by the separation charger 8. The sheet is separated from the surface of the paper sheet 1 and sent to a fixing device 23 by a conveyor belt 22, where the image is fixed thereon and then discharged onto a paper discharge tray 24. After the transfer, the photosensitive drum 1 is cleaned by a cleaning device 9. The eraser 2 removes l-ner and charges remaining on the surface, preparing it for the next copying process.

Either the automatic paper feed mechanism 20 or the manual paper feed mechanism 30 is selectively used. In case of automatic paper feeding, copy machine 10
Print key 82 (9th
When the image forming system including the photoreceptor drum 1 is moved to the star 1-L by the operation shown in FIG. Drive of the optical system 10 is started by a scan start signal outputted along with the conveyance, and the copy paper is fed in synchronization with the image forming operation. The number of copy sheets is not necessarily one, but multiple sheets may be pushed out by the rotation of the paper feed roller 25 or 26.
' will send out only the top layer.

In the handling mechanism 27, 27', the upper roller 27a
27a' is the lower roller 27b in the feeding direction.

27b' is rotationally driven in the push-back direction in the direction of the arrow in the drawing. The second and subsequent sheets of copy paper that are pushed out together with the top layer copy paper by the paper feed roller 25 or 26 are pushed back by the lower rollers 27b and 27b', and only the top layer copy paper is sent to the next intermediate roller pair 28. or 28'
sent towards. The intermediate roller pair 28.28' is
As will be described later, the timing roller pair 21 is associated with the timing roller pair 21 in the next stage, and its drive is controlled.

On the other hand, in the case of manual paper feeding, when copy paper is inserted from the manual paper insertion slot 32 and the sensor 34 detects this,
The manual feed roller 33 rotates to feed the copy paper into the machine, and at the same time or a little later, the photosensitive drum 1 and the like start to be driven in the same way as when the print I key 82 is operated. Then, the manually fed copy paper is temporarily stopped and on standby at the detection part of the copy paper leading edge detection switch 35, and when the preliminary drive process including the rotation of the photosensitive drum 1 is completed, the paper feed roller 33 rotates again. This sends it onto the plane.

In addition, size detection switches 5WII to 5W14 and 5W21 to 3W are installed in each cassette mounting section of the automatic paper feeding mechanism 20.
24 is provided, and the operating state of the switch is changed by the arrangement of protrusions or magnets (not shown) provided on the cassettes 91 and 92 to be loaded, and the size of the loaded copy paper is determined by a 4-bit binary code. It is designed to be determined by

Next, the ADF2 installed on the top of the copying machine] and the top of the OO.
00 will be explained. The ADF 200 basically includes a document feeding section 201 that stocks documents and feeds them one by one, and a conveyance heald 105 that conveys the sent documents over the top surface of the document table glass 16 and stops them at a predetermined position on the surface of the glass 16. The document transport unit 202 also includes a document transport unit 202 that sends the document onto a paper discharge tray 204 after scanning the document. The document transport unit 202 can also be used independently as a manual document transport device. That is, the document transport section 2
02 is provided with an original holding cover 205 that opens and closes the upper surface of the original platen glass 16, and by setting the original on the original platen glass 16 at a predetermined angle, copying operation in manual mode can be performed. It turns out. Incidentally, the structure around the original holding cup 205 will be described later.

[Original size detection sensor]

In the optical system 10, a long lamp as shown in FIG. A sensor support arm 40 having a shape is arranged. The base end 40a side of the sensor support arm 40 is located at the reference end (A in the figure) for aligning documents, and is swung to the copying machine frame 101 via a coil spring 41 as shown in FIG. 3.4. It is movably supported and is configured to be driven into and out of a position below the document table glass 16 by a solenoid 42.

The details of the connection structure between the solenoid 42 and the sensor support arm 40 are as follows: One end 43a of an L-shaped crank lever 43, which is pivotally supported around a horizontal axis in the center, is connected to the movable shaft portion 42a of the solenoid 42, and the pin at the other end is The portion 43b is inserted into and locked into the elongated hole 4.4b of the swing lever 44 connected to the base end 40a of the sensor support arm 40.

When the solenoid 42 is not energized, the crank lever 43 stands up as shown by the solid line in FIG. 3, and the sensor support arm 40 swings back to the state shown by the solid line due to the restoring force of the coil spring 41. There is. This return position is a position where the original platen glass 16 is retracted from below to the side, as shown in FIG. 2 (A) in plan view. When the solenoid 42 is energized, the sensor support arm 40 swings against the restoring force of the coil spring 41 to the position shown in FIG. . At the (mouth) position, the base end of the sensor support arm 40 comes into contact with the stopper 45, so the sensor support arm 40 is held at that position. Note that the swing angle θ at this time is 30° in this embodiment.

For example, four sensors 4 are mounted on the sensor support arm 40.
．． 6, 47, 48, and 49 are arranged at predetermined intervals in the longitudinal direction. As shown in FIG. 5, each of the sensors 46 to 49 includes a light emitting element 46a that emits light in an oblique direction and a light receiving element 46b that receives light from above. Therefore, Fig. 5 (
As shown in (a), when there is no original on the original platen glass 16, the light emitted from the light emitting element 46a is emitted from the original platen glass 6
The light does not enter the light receiving element 46b.

On the other hand, when a document 300 is placed on the document table glass 16 as shown in FIG. Therefore, diffusely reflected light from the irradiated portion of the document enters the light receiving element 46b. The light receiving element 46b changes to the "L" level due to the incidence of this diffusely reflected light. The light emitting element and light receiving element of each of the sensors 46 to 49 are synchronized by a synchronization circuit 50 shown in FIG. 6, so that only the light from the light emitting element is received by the light receiving element.

When the sensor support arm 40 is swung to the position shown in FIG. 2 (b), the document size can be detected from the detection states of the sensors 46 to 49.

The reason for this is explained with reference to FIG. 2. First, when an A5 original is placed vertically on the original platen glass 16 as shown by A5T, all sensors 46 to 49 are off from the original A5T, so the "H" level is detected. output (see ■ in Table 1).

Next, if you place the B5 document vertically as shown by B5T,
Since only the sensor 48 enters below the document B5T, only the sensor 48 changes to the "L" level (see ■ in Table 1).

Next, when the A4 document is placed vertically as shown by A4T, the sensors 48 and 49 will be placed below the document A4T, so these two sensors 48 and 49 will change to the "L" level (see ■ in Table 1). ).

When a B4 original is placed vertically as shown by B4T, the remaining three sensors except sensor 46 are placed under the original B4T, so only sensor 46 is at "H" level, and the other sensors are at "H" level.
L" level (see ■ in Table 1). Below, the sensor output when an A3 document is placed vertically is shown in [Phase] in Table 1, and B5
The sensor output when the document is placed horizontally is shown in ■ in Table 1.
The sensor output when the document is placed horizontally is as shown in 0 in Table 1.

Note that the sensor output patterns shown in ■■, ■~@, ■, and ■ in the table are patterns that are not found in the detection of document size.

On the other hand, when the sensor support arm 40 is retracted to the position shown in FIG. 2 (A), it can be detected from the detection states of the respective sensors 46 to 49 that the sensor support arm 40 is in the retracted position. The reason for this is explained using Figure 4.
The support frame 102 that supports and fixes the document table glass 16 in the portion facing the sensor 47 and the sensor 49 has an opening 10, respectively.
2a and an opening 102b are bored, and each sensor 47
・The light emitted from the light emitting elements 47a and 49a of 49 is the machine frame 1.
The light is irradiated onto the back surface of the upper exterior plate 101a of No. 01, and its diffused reflection is directed onto each of the light receiving elements 47b and 49b, respectively.

In addition, the light emitting elements 46a and 48a of each of the other sensors 46 and 48
The light emitted from the support frame 102 illuminates the back surface of the support frame 102, but since the gaps between the light emitting elements 46a and 48a and the support frame 102 are small, no light enters the light receiving elements 46b and 49b. Therefore, when the sensor support arm 40 is in the retracted position, the light receiving elements 47b and 49b change to "■" level, and the other light receiving devices 46b and 48b output an output of "'H" level (■ in Table 1). reference).

However, if a non-standard size document, for example a square document with long sides of B5, is placed on the document table glass 16, the sensor 47
Since the sensor 48 enters below the document, the two sensors 47 and 48 turn to the "L" level (see ■ in Table 1). Therefore, if such a combination of sensors is used to detect the retracted position of the sensor support arm 40, when a document of the above-mentioned non-standard size is placed on the document glass 16, it will be mistakenly recognized that the sensor support arm 40 has been retracted. There is a risk.

Therefore, in the embodiment of the present invention, a sensor combination that is not detected even when a non-standard size original is placed on the original platen glass 16 is used to detect the retracted position of the sensor support arm 40 (Table 1 (See ■).

c below, margin] Table 1 From the above results, it can be seen that the sensor output patterns differ depending on the document size and whether the document is placed horizontally or vertically. Therefore, it is possible to determine the document size from the output pattern of all the sensors.

Further, it is possible to determine whether the sensor support arm 40 is in the retracted position from one pattern (see ■ in Table 1) of the sensor output patterns that are not used for detecting the document size.

[Configuration around the document frame cover]

FIG. 7 is an external perspective view of the copying machine showing the document frame cover 205 in an open state, and FIG. 8 is a side sectional view showing the structure around the document frame cover. The copying machine main body 100 is provided with a switch O5W for detecting whether the document frame cover 205 is opened or closed. That is, as shown in FIG.
A switch O8W consisting of a reed switch is provided at the front right corner of the upper surface of the document frame cover 205.
When the switch O3W is closed, the switch O3W senses the magnet 206 attached to the front right end of the back side of the original frame cover 205, and is turned on to detect the closed state. On the other hand, when the document frame cover 205 is opened, the switch ○SW is turned off to detect the open state.

In this way, the open/closed state of the document frame cover 205 is detected. Then, when the switch ○SW is turned on, the controls of the ADF 200 and the copying machine main body 100 are related to each other, and the operation mode of the copying machine main body 100 is set to A.
The mode will be switched to automatic mode by DF200. This switching control is performed by a CPU 70, which will be described later.

Note that the document frame cover 205 is supported by a hinge mechanism 207 shown in FIG. 8 so as to be openable and closable.

A switch KSW is provided below the hinge mechanism 207 to detect the opening angle of the document frame cover 205, and depending on the detection result (on/off state) of this switch, the document frame cover 205 is set at the reference angle (30°). It is now possible to detect whether the door is open or not.

The details of this detection mechanism are shown in FIG.

A bushing rod 209 that contacts the back surface of the document frame cover 205 and sets its opening angle to 30 degrees is attached to a base plate 208 that supports the rear end of the document table glass 16 so as to be able to rise and fall. That is, the bushing rod 209 is connected to the plywood 208 with the locking part 44' 209a provided at the upper and lower middle parts of the bushing rod 209.
The opening angle of the document frame cover 205 is set to 30 degrees by the spring pressure of the spring 211. ing. The reason for setting the angle to 30° here is to consider ease of use.

The lower end of the bushing rod 209 is linked to a pressing lever 213 that presses a sensing lever 212 of the switch KSW to turn it on and off.

The pressing lever 213 is rotatably supported by a horizontal support pin 214 that supports the intermediate portion of the pressing lever 213.

In this way, when the document platen glass 16 is moved in the closing direction, this pushes down the bushing rod 209 against the biasing force of the spring 211, causing the front side of the pressing lever 213 to tilt downward, and the rear end of this to the sensing lever 212. Therefore, the switch KSW is turned off. Note that when the document frame cover 205 is completely closed, a locking means (not shown) operates, and the document frame cover 205 is locked in the closed position against the biasing force of the spring 211.

On the other hand, when the document frame cover 205 is opened from the closed position, the spring 211 raises the bushing rod 209.
The opening angle of the document frame cover 205 is set to 306. Then, in this state, the pressing lever 213
is tilted (or approximately horizontal) contrary to the above, and the rear end of this presses the operating lever 212, so the switch K
SW is turned on.

Thus, when the document frame cover 205 is opened more than 30', the switch KSW is turned off, and when it is less than 30', the switch KSW is turned on. That is, this switch KSW is connected to the document frame cover 20.
It functions as an angle detector that detects the opening angle with a critical point of 30 degrees. The detection result of the switch KSW is input to the CPU 70 similarly to the switch ○SW.

[Configuration and operation of control circuit]

FIG. 9(a) is a block diagram showing the control circuit of the copying machine, and FIG. 9(b) is a partial plan view showing the operation panel 75 and display section 90 provided on the upper front side of the copying machine main body 100.

The CPU 70 refuses to control this copying machine,
Detection signals from various switches and key input signals from pressing various keys on the operation panel 75 are received via the input port, and the entire copying operation is controlled via the output port. Specifically, the detection signal is sent to switch 5.
W11-14° On/off signals of switches SW21-24, open/close detection signal of document frame cover 205 by switch ○SW, document frame cover 205 by switch KSW
A detection signal for detecting whether the opening angle is 30° or more (hereinafter referred to as opening angle detection signal) and sensors 46 to 49
This is the detection signal of

Key human input signals include numeric keypad 80. All reset key 81. Print key 82 Copy mode selection key 8
3. Copy paper selection key 84. Business method selection key 85 (
(key for selecting AE (automatic exposure mode) or manual exposure mode), operation manual key 86 for setting copy density to be lighter in manual exposure mode, operation manual key 87 for setting copy density to darker in manual exposure mode, etc. It's a signal.

The CPU 70 also outputs the main motor M1 and other motors M2. A drive signal to M3, an energization control signal for the solenoid 42, and a display signal to the display section 90 are output.

Furthermore, a memory 71 is connected to the CPU 70 for storing and holding data such as document size.

The display section 90 is made up of a large number of LEDs arranged in a matrix, and is provided to the left of the various key switches as shown in FIG. Display section 9 consists of a magnification selection display section 92, a manual mode display section 92a, a paper size etc. display section 93, a paper feed area display section 94, a MesoSef display section 95, etc.
0 is displayed on these various display units, that is, the corresponding LED is lit according to the logical result of the decoder 72. In addition, O I/U ♀ 1 (selection and auto magnification selection display section 92
Switching between the manual mode display section 922 and the manual mode display section 922 is selectively performed by turning on the copy mode selection key 83.

FIG. 10 is a main flow showing the copy operation controlled by the control circuit. When the device is activated, step S1
Set the internal timer with . The internal timer controls one routine of the copying operation, and control in each process is measured based on this timer. When this timer is counted, steps 32 to S6 are advanced and predetermined processing is performed. That is, if there is a key pressed on the operation panel 214, it is read (S2), the size of the original set on the platen glass is detected (S3), and an abnormality is detected (details will be described later) (S4). , then performs a copying operation (S5), and at that time performs incidental processing such as displaying an error if there is a paper jam (S6). When all the above processes are completed, the process waits for the time set in the internal timer to elapse (S7), and repeats the processes from 32 to S6 again.

The document rise detection process in step S3 above is performed automatically by the ADF 200 in the ADF mode, and when it is performed in a non-ADF mode.
Both processes are shown when detecting the size of a document placed on the document table glass by swinging the sensor support arm 40 in the DF mode.

This process is shown in detail in the →knob routine shown in FIG. In this subroutine, first, step S8
Then, the sensor support arm 40 swings below the document table glass, and in flowchart I., this swing is called arm opening. ), judge whether the conditions are good or not. These steps S81 to S85 and S388 are not shown in the subroutine of FIG. 12.

That is, if the device is in the process of copying (S81), an original is set in the ADF even if it is not in the process of copying (S82), and if the device is set in the ADF mode (S83), even if the device is not in the ADF mode. Even if the document holding cover 205 is
If the arm is closed at an angle of less than 0° (S84), the arm open flag is set to O. This opens the arm to the east of the prefecture. On the other hand, if the copy operation is not in progress and the AD
When the mode is not F mode and the document holding cover 205 is open, the arm open flag is set to 1, and it is judged that the arm open condition is satisfied.

If the arm release flag is set to 1 in step 385, the following steps S86 and S87 will be performed. That is,
It is necessary to judge whether the switch ○SW is at the off-edge (state B in which the document holding cover 205 is opened from the completely closed state) (586), and when it is confirmed that it is at the off-edge, the previous time stored in the memory 71 is The document size detection data at the time of detection is reset and the process returns to the main flow.

By detecting the off-edge of the switch O3W in S86, it is possible to prevent copying errors. That is, some operators may open the document holding cover 205 at a small angle of less than 30 degrees and manually set the document on the document table glass 16 to perform a copying operation.
If W is not provided, the CPU 70 will not be able to know that the original has been replaced. On the other hand, in this state, the switch KSW is in the on state, so the CPU 70 determines that the copying operation is in progress. Therefore, even though the size of the original has been changed, copies will be made in APS and AMS modes based on the previous detection data.
This results in a copy process.

However, if the switch ○SW is provided, it can be determined that the original has been exchanged based on the detection results of this and the switch KSW, so that the copying waste as described above does not occur.

FIG. 13 is a flowchart showing a subroutine at the time of abnormality detection, including the case where the original is replaced as described above. That is, the CPU 70 first determines whether the print key 82 on the operation panel 75 is turned on (3101).
, Once this is confirmed, it is then determined whether the APS or AMS mode is in effect (3102). When it is confirmed that the APS or AMS mode is in effect, it is determined whether or not there is document size detection data in the memory 71 (3103).

If there is no original size detection data, that is, if the previous original size detection data in the memory 71 has been reset because the original was replaced, copying operations in APS and AMS modes cannot be performed. Therefore, a serviceman call 95a (see FIG. 9(b)) may be displayed on the message display section 95 of the display section 90, or, for example, r
A message (warning) such as "Auto mode cannot be used" is displayed to notify the operator (S104), and then other abnormalities such as paper jams are detected (5105) and the process returns to the main flow.

Note that when the original size detection data in the memory 71 is reset, in order to perform the copying operation in automatic mode again, it is necessary to detect the original size again and store the updated data in the memory 71. The update operation is shown in FIG. 14 as the update operation subroutine 3.
42. That is, first, it is determined whether the switch KSW is on (the state in which the document holding cover 205 is closed from the open position) (5421), and once this is confirmed, the detection signals from the sensors 46 to 49 are read in again, the document size is determined, and the memory 71 5422), and then returns to the main flow.

Now, the flowchart 1 shown in FIG. 11 will be explained again. When the judgment is completed, the program proceeds to step S9 and checks the count value of the state counter. The state counter can have seven types of state values from "0" to "6", and the values are rewritten as the program advances through each routine from "0" to "6".

Each of the routines "O" to "6" refers to a group of steps on each multi-branch line branched from step S9.

Each routine from O" to "6" includes steps S1.1,
313. S24. S33. S36,545S53. S6
3. It has a processing step of changing the state 1 value of the state counter.

When the device is first started, the state counter's state counter is "0", so the program is "0".
Step through the routine and return to the main flow. When the program advances to step S9 again, the state value of the state counter is checked, and the routine jumps to the routine instructed by the state value. After completing the routine, return to the main flow again,
Step through the main flow. When step S9 is reached, the routine jumps to the routine indicated by the state 1 value of the state counter and advances through that routine. Repeat this operation thereafter.

Next, each routine from "O" to °゛6 will be explained. In the "0" routine, first, in step S10, the data at the time of initial setting (at startup after troubleshooting, at power on, etc.) and the previous detection After clearing the current data, set the state counter to "1" in step 311]
Return to main routine.

1'' routine, it is determined in step S12 whether the test scan has been completed, and if it has been completed,
Proceeding to step S13, the state counter is set to "'2", and if the process has not ended yet, the process returns to the main routine without changing the contents of the state counter. Then, each time the routine advances to "1" and waits for the test scan to be performed. When the test scan is completed, the process advances to step S13 and the state counter is set to u2'. Note that the test scan is a preliminary scan that is performed to check for abnormalities in the optical system at the time of initial setting, for example, when the power is turned on, or when returning after clearing a paper jam.

In the routine "2", if the arm open flag is set to "l" in step S21, the process proceeds to step S22, where the arm solenoid 42 is turned on and the sensor support arm 40 is swung below the document table glass 16. Subsequently, in step 323, a timer TA is set to set the time required for the arm 40 to stop after it starts swinging.

Then, in step S24, the state counter is set to "3".
Set to . On the other hand, the flag is set to ``1'' in step S21.
”, the program returns to the main routine without proceeding through steps 822 to 24. Therefore, in this case, the program continues in the routine “2” until the flag is set to “1”. I will be running.

In the routine "3", it is determined in step S31 whether the arm release flag is set to "1", and
In the case of s, the process advances to step S32 and it is determined whether or not timer TA has time-amplified. If the time is up, the process advances to step S33 and the counter is set to 4. If the time has not expired yet, return as is.

On the other hand, if it is determined in step S31 that the flag is not "l", in such a case, as explained in the subroutine of FIG. (1) In any of the three cases when the document holding cover 205 is closed at an angle of less than 30 degrees, the program proceeds to step S34 and turns off the arm solenoid 42. As a result, the sensor support arm 40 begins to swing toward the retracted position due to the elastic restoring force of the coil spring 41. Then, in step S35, the time required for the arm 40 to be retracted to the retracted position is set in the timer TA, and the state counter is set to "5".

In the routine "4", it is determined again in step S41 whether the arm open flag is "1", and if the flag is "1", the process proceeds to step 342, and the detection signals of the sensors 46 to 49 are acquired as described above. , the document size is determined and the document size data in the memory 71 is updated. Then, when the operator finishes setting the original on the original platen glass 16 and closes the original holding cover 205, the flag is set to "O" in the arm open judge routine shown in FIG.
．． 1 to 343, the arm solenoid 42 is turned off, and in step S44, the time required for the arm 40 to be retracted to the retracted position is set. after that,
In step S45, the state counter is set to 5",
Return to main flow. The arm solenoid 4
2 is turned off, the sensor support arm 40 begins to swing in the retracting direction due to the elastic restoring force of the coil spring 41.

In the routine "5", at step 351 the timer T-
Judgment was made as to whether A had time-amplified.
When the time is up, timer T-B is set in step S52.
, and in step S53, the state counter is set to “
6''. The timer T-B is a timer for setting a time for trouble detection, and is set to a predetermined time that allows for sufficient time for the arm to be retracted.

In the routine "6", the arm 40 is
A determination is made as to whether or not the person has evacuated.

This judgment takes in the detection signals of the sensors 46 to 49,
It can be determined from this detection signal.

If the arm 40 is not retracted, the process advances to step S64 and it is determined whether the timer T-B has timed up. If the timer TB times up while the arm 40 is not retracted, the process advances to step S65, where an error is displayed on the display section 90 and a process is performed to prohibit the copying operation.

Next, when the arm 40 is completely retracted before the timer T-B times up in step S61, step S62
Proceed to step 3, clear timer T-B, and
At step 63, the state counter is set to "2". Therefore, every time a new document is set from now on, the process will start from routine "2".

Note that the exit cover turns of the sensors 46 to 49 for confirming the retraction of the sensor support arm 4o in the above embodiment can be changed as appropriate as long as they are not used for detecting the document size.

Further, in the above embodiments, the present invention is applied to a copying machine equipped with an ADF, but it goes without saying that the present invention can be applied to a copying machine not equipped with an ADF.

According to the present invention described above, when replacing the original with the original frame cover opened below the reference angle, the previous original size detection data is automatically reset. , no copying errors occur. Therefore, usability can be greatly improved.

[Brief explanation of the drawing]

FIG. 1 is an overall view of a copying machine to which the present invention is applied, FIG. 2 is a plan view showing a sensor support arm, FIG. 3 is a perspective view of the arm, FIG. 4 is a side view of the arm, and FIG. Figure 6 is a diagram explaining the detection principle of the sensor, Figure 6 is a diagram showing the electric circuit of each sensor, Figure 7 is an external perspective view of the copying machine showing the document frame cover open, and Figure 8 is the document Side sectional view showing the detection mechanism for detecting the opening angle of the frame cover, Figure 9 (A)
9(b) is a block diagram showing the control circuit of the copying machine, FIG. FIG. 11 is a flowchart showing a subroutine for document size detection, FIG. 12 is a flowchart showing a subroutine for arm open judge, FIG. 13 is a flowchart for abnormality detection subroutine, and FIG. 14 is a flowchart for updating document size detection data. This is a flowchart 1 showing a subroutine. 16...Original table glass, 46-49...Sensor, 4
0...Sensor support arm, 70...CPU, 71.
...Memory, 75...Operation panel, 9o...Display section, 205...Document frame cover, ○SW...Document frame cover opening/closing detection switch, KSW...Document frame cover opening Angle detection switch. Patent applicant Minolta Camera Co., Ltd. Figure 12 Figure 13

Claims (1)

[Claims] (1) An image reading device equipped with an original size detection means for detecting the size of an original placed on an original platen glass, comprising: a memory device that stores the detection result of the original size detection means; and the original platen glass. An angle detector detects whether the opening angle of the document holding cover that opens and closes the top side is greater than or equal to a reference angle, and sets the document size detection means to execute detection when the angle is greater than or equal to the reference angle; An image reading device comprising: an opening/closing detector for detecting an opening/closing state, and configured to reset the stored contents of the memory device when the document holding cover performs an opening operation.