JP2020172381A - Image formation device - Google Patents

Abstract

To notify the existence of a foreign matter such as a paper sheet on a back side of a paper feeding cassette container.SOLUTION: This device includes: a paper sheet size detection part for detecting size of a paper sheet set in a paper feeding cassette container; a control part which controls lift-up of the paper sheets when either of a plurality of detection parts of the paper sheet size detection part is detected and it is determined that the paper feeding cassette container is set; a paper sheet presence detection part for detecting presence or absence of the paper sheet set in the paper feeding cassette container; and a notification part for notifying a state of the paper feeding cassette container. When the paper sheet size detection part has become a predetermined detection state, a first notification content is notified, and after the paper sheet presence detection part has become a non-detection state in a state where the paper sheet size detection part has become the predetermined detection state, when either of the plurality of detection parts of the paper sheet size detection part is detected, the instruction to switch to a second notification content is performed.SELECTED DRAWING: Figure 10

Description

The present invention relates to an image forming apparatus including a paper size detecting device for detecting the size of paper loaded in a paper cassette container.

A conventional image forming apparatus provided with a paper size detection function in a paper cassette container abuts on the rear end of the loaded paper in the paper transport direction and the end in the width direction orthogonal to the loaded paper transport direction. By setting the regulation plate according to the paper, a member having a plurality of protrusions at positions facing the paper size detection sensor and operating in conjunction with the regulation plate can obtain a detection result of a predetermined paper size detection sensor. The configuration is adopted.

The paper size detection device of Patent Document 1 includes a pair of width direction regulation plates, a rear end regulation plate, a paper size detection sensor, a rotation member for width direction regulation plate, and a rotation member for rear end regulation plate. There is. The paper size detection sensor has a plurality of push switches, the rotating member for the width direction regulating plate has a plurality of first convex portions, and the rotating member for the rear end regulating plate has a plurality of second convex portions. Has. A plurality of composite convex portions are formed by the plurality of first convex portions and the plurality of second convex portions, and the composite convex portions facing the plurality of push switches are formed according to the positions of the width direction regulating plate and the rear end regulating plate. Changes. Since the composite convex portion presses the opposite push switches, the paper size can be detected depending on the states of the plurality of push switches. The state of the plurality of push switches is a combination of the states (ON or OFF) of each switch.

The position of the rotating member may be slightly deviated from the specified position according to the paper size due to the variation in the structure of the paper size detection sensor and the rotating member, or the variation in the operation of the regulation plate by the user. If the rotating member is fixed at a displaced position, false detection of paper size may occur.

Therefore, by providing the fixed position correction means, the fixed position correction means corrects the position of the rotating member to a predetermined position immediately before fixing the rotating member. As a result, the positional accuracy of the rotating member is improved, and false detection of the paper size is prevented.

Japanese Unexamined Patent Publication No. 2006-188357

However, the paper size detection device of Patent Document 1 has the following problems. When pulling out the paper cassette container for jam processing or paper replenishment, the paper may fall to the back side of the paper cassette container. After that, when the pulled out paper cassette container is returned, the dropped paper is jammed between the paper size detection sensor and the convex portion that presses the paper size detection sensor, and the paper size detection sensor cannot detect correctly.

At present, in such a situation, the display unit displays a display prompting the user to position the regulation plate in the correct position. Alternatively, it is displayed that the paper size of the paper cassette container is undefined because the regulation plate is not in the predetermined position. Furthermore, it is difficult to confirm that the paper cassette container is not removed from the image forming device on the back side of the paper cassette container, and the paper is on the back side of the paper cassette container just by pulling out the paper cassette container. I can't figure it out.

Originally, this situation cannot be resolved unless the paper that has fallen to the back of the paper cassette container is removed. However, due to the above, the paper that has fallen to the back of the paper cassette container must be removed. In particular, the user does not easily notice it, so there is a problem that the downtime becomes long.

In order to solve the above problems, the image forming apparatus according to the present invention is
It is provided so as to be movable in a paper cassette container capable of loading a plurality of sheets of paper, and has a regulating plate that comes into contact with the paper loaded in the paper cassette container and a plurality of detectors. The paper size detection unit for detecting the size of the paper set in the paper feed cassette container based on the detection result of the detection unit and the paper size detection unit operate in conjunction with the movement of the regulation plate to form a plurality of convex portions and the paper size. When any of the movable member installed at the position of the paper feed cassette container facing the detection unit and detected by the paper size detection unit and the plurality of detection units of the paper size detection unit is detected, the supply is supplied. A determination unit that determines that the paper cassette container is set, and a control unit that lifts up the paper inside the paper cassette container when the determination unit determines that the paper cassette container is set. , A paper presence / absence detection unit that detects the presence / absence of paper loaded in the paper feed cassette container, a notification unit that notifies the state of the paper feed cassette container, and an instruction to notify the notification unit of a predetermined notification content. It has a notification instruction unit, and when the paper size detection unit is in a predetermined detection state, it instructs the notification unit to notify the first notification content, and the paper size detection unit is in a predetermined detection state. If any of the plurality of detection units of the paper size detection unit detects after the paper presence / absence detection unit is in the non-detection state in this state, the notification unit is switched to the second notification content. It is characterized by instructing.

According to the image forming apparatus according to the present invention, even if the paper falls to the back side of the paper feed cassette container and the paper size cannot be detected correctly, the user still has the paper on the back side of the paper feed cassette container. It is possible to inform that there is a possibility of doing so.

Overall configuration diagram of the image forming apparatus 100 Block diagram of the control unit of the image forming apparatus 100 Configuration diagram of the paper cassette container 4 (front side, at the lowest point of the middle plate and when lift-up is completed) Configuration diagram of the paper cassette container 4 (side side, at the lowest point of the middle plate) Configuration diagram of the regulation plate 317, the paper size detection sensor pressing member 316, and the paper size detection sensor 309. Single view of paper size detection sensor 309 A table showing the combination of the state of the pressing unit 318 and the detection state. The figure when the paper P1 is jammed in the paper cassette container 4. Flow chart showing the start-up operation of the image forming apparatus 100 Flow chart showing the operation of the paper cassette container 4

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

FIG. 1 is an overall configuration diagram of an example of an image forming apparatus according to the present invention.

As shown in FIG. 1, the image forming apparatus 100 is a tandem type intermediate transfer type full-color printer in which image forming portions 1a, 1b, 1c, and 1d are arranged along the downward surface of the intermediate transfer belt 3. The paper cassette container 4 can be pulled out from the main body 30, and the user can replenish the paper P to the paper cassette container 4 and store it in the main body 30 again. Since the paper cassette container 4 is provided with the same paper cassette container in the lower stage and has the same configuration in the upper and lower stages, the description of the paper cassette container in the lower stage is omitted.

The paper feed roller 8 separates the paper P drawn from the paper feed cassette container 4 one by one and sends it out to the resist roller 9. The resist roller 9 receives the paper P in a stopped state and puts it on standby, and feeds the paper P to the secondary transfer region T2 in time with the toner image of the intermediate transfer belt 3.

The image forming portions 1a, 1b, 1c, and 1d are configured to be substantially the same except that the toner colors used in the respective developing units are different from yellow, magenta, cyan, and black. The image forming unit 1d will be described below as a representative, but the end of the reference numeral will be omitted unless necessary.

The image forming unit 1 is assembled in a replacement unit (process cartridge) including the photosensitive drum 10. The photosensitive drum 10 has a photosensitive layer having a negative charge polarity formed on the outer peripheral surface of an aluminum cylinder, and a driving force is transmitted from a drive motor (not shown) to rotate the photosensitive drum 10 at a predetermined process speed.

The photosensitive drum 10 is charged to a uniform negative electrode potential by using a charging roller 41 built in the image forming unit 1. The exposure apparatus 6 scans a laser beam obtained by ONOFF-modulated scanning line image data obtained by developing a black separated color image with a rotating mirror, and writes an electrostatic latent image of the image on the surface of the charged photosensitive drum 10. The electrostatic latent image written on the photosensitive drum 10 is reverse-developed into a toner image by adhering toner to the developer 51 built in the image forming unit 1.

The primary transfer roller 2 presses the intermediate transfer belt 3 to form a primary transfer region T between the photosensitive drum 10 and the intermediate transfer belt 3. When a positive DC voltage is applied to the primary transfer roller 2, the negative electrode toner image carried on the photosensitive drum 10 is primarily transferred to the intermediate transfer belt 3 passing through the primary transfer region T.

The intermediate transfer unit 20 is an exchange unit that is arranged above the image forming unit 1 and can be integrally attached to and detached from the image forming apparatus 100 without attachment / detachment related to rotational drive, and supports the intermediate transfer belt 3. Includes mechanism and drive mechanism. The intermediate transfer belt 3 is supported by being hung on a tension roller 27, a belt drive roller 26, a secondary transfer inner roller 25, and a primary transfer tension roller 28, 29, and is driven by the belt drive roller 26 in the direction of arrow R2. Rotate. The intermediate transfer belt 3 is an endless belt member that does not expand or contract, and is hung between the belt drive roller 26 and the secondary transfer inner roller 25 so as to reverse the rotation direction.

Further, the intermediate transfer unit 20 includes a density detection sensor 80 that detects the density of the toner image on the intermediate transfer belt 3.

Primary transfer rollers 2a, 2b, 2c, and 2d are assembled in the intermediate transfer unit 20 in correspondence with the image forming portions 1a, 1b, 1c, and 1d. The primary transfer rollers 2a, 2b, 2c, and 2d are spring-loaded toward the photosensitive drums 10a, 10b, 10c, and 10d, respectively, so that the intermediate transfer belt 3 abuts on the photosensitive drums 10a, 10b, 10c, and 10d. To form the primary transfer region of the toner image.

The secondary transfer region T2 is configured by abutting the secondary transfer outer roller 22 against the intermediate transfer belt 3 whose inner side surface is stretched by the secondary transfer inner roller 25. The secondary transfer inner roller 25 is assembled in the intermediate transfer unit 20, while the secondary transfer outer roller 22 is assembled in the main body 30 of the image forming apparatus 100. The secondary transfer inner roller 25 stretches the intermediate transfer belt 3 in the secondary transfer region T2 of the toner image. By applying a positive DC voltage to the secondary transfer outer roller 22 from a power source (not shown), a transfer electric field of a toner image is formed between the secondary transfer inner roller 25 and the secondary transfer inner roller 25 connected to the ground potential.

The fixing device 5 forms a heating nip by pressing the pressurizing roller 5b against the fixing roller 5a provided with the fixing heater. The paper P is subjected to heating and pressurization to melt the toner image in the process of being sandwiched and conveyed by the heating nip, and the full-color image is fixed on the surface. The paper ejection tray 7 is loaded with the fixed paper P that has passed through the paper ejection roller 11.

Next, FIG. 2 shows a block diagram of the control unit of this device.

The control unit 200 is responsible for driving each load in the apparatus, collecting and analyzing information on sensors, controlling images, and exchanging data with the operation unit 202, that is, the user interface. The internal configuration of the control unit 200 includes a CPU 201a in order to play the above-mentioned role.

The CPU 201a also executes various sequences related to a predetermined image formation sequence by a program stored in the ROM 201b mounted on the control unit 200. Further, the CPU 201a has a timer circuit (not shown) by an internal clock, and the time can be measured.

At that time, a RAM 201c is also mounted in order to store rewritable data that needs to be temporarily or permanently stored.

In the RAM 201c, for example, a high voltage set value for the high voltage control unit 205, various data described later, image formation command information from the operation unit 202, and the like are stored. The RAM 201c is configured to hold data even when the power of the image forming apparatus 100 is turned off by a battery or the like (not shown).

In addition to obtaining information such as the copying magnification and the density setting value set by the user, the operation unit 202 includes information on the state of the image forming apparatus 100, such as the number of images formed, information on whether or not an image is being formed, and the occurrence of jam. Data is sent to show the user about the location and the location. In addition, it accepts the serviceman to adjust the cash register position, adjust the density, etc., and to display the guidance of the initialization operation or start the operation when the main body is installed or the developer is replaced, if necessary.

The image forming apparatus 100 arranges DC loads such as a motor and a clutch / solenoid (hereinafter abbreviated as CL / SL) and sensors such as a photo interrupter and a micro switch in various places inside the apparatus. By driving the motor and each DC load as appropriate, the transfer material is conveyed and each unit is driven, and various sensors monitor the operation. The CPU 201a acquires the sensor signal by making the signal from the various sensors 214 in a state where the signal can be detected via the sensor IF209 including a pull-up / pull-down circuit (not shown), a filter circuit (not shown), and the like.

The paper size detection sensor 309 can detect the size of the paper P loaded on the paper cassette container 4, and can also detect whether or not the paper cassette container 4 is stored in the main body 30. The paper presence / absence detection sensor 311 can detect whether or not there is paper P in the paper cassette container 4. Based on the signals from the various sensors 214, the CPU 201a controls each motor 212 by the motor control unit 207.

The lifter motor 310 can lift up the paper P loaded in the paper feed cassette container 4 to a height at which paper can be fed. At the same time, the CPU 201a operates the CL / SL 213 by the DC load control unit 208 to smoothly proceed with the image forming operation. Further, the CPU 201a inputs a high-voltage control signal from the high-voltage control unit 205 to the high-voltage unit 206, and the high-voltage unit 206 applies an appropriate high voltage to the charging roller 41, the developing device 51, the primary transfer roller 2, and the secondary transfer inner roller 25. It is applied.

The fixing roller 5a has a built-in fixing heater 211 for heating the roller, and the fixing roller 5a is provided with a thermistor 204 for measuring the temperature of the fixing heater 211.

After the A / D 203 converts the resistance value change of the thermistor 204 in response to the temperature change of the fixing roller 5a into a voltage value, the CPU 201a acquires it as a digital value. Based on this temperature data, the CPU 201a controls the AC driver 210 so that the fixing roller 5a has a predetermined temperature.

Further, the image control unit 220 processes the image data input from the outside and sends the image data to the image forming unit 1.

3A and 4A are schematic views showing the configuration inside the paper cassette container 4, and are views of the image forming apparatus 100 viewed from the front side and side views, respectively. Further, FIG. 5 shows a regulation plate 317 that regulates the rear end of the paper in the paper transport direction or the paper width direction orthogonal to the paper transport direction with respect to the loaded paper P held in the paper feed cassette container 4, and is linked to the regulation plate 317. It is a figure of the paper size detection sensor pressing member 316 which operates and presses the pressing part 318 of the paper size detecting sensor 309. Further, FIG. 6 is a single view of the paper size detection sensor 309 pressed by the paper size detection sensor pressing member 316.

The paper cassette container 4 is stored in the main body 30 by loading the paper P on the middle plate 305. A roller 313 is provided at the bottom of the paper cassette container 4, and when the user pushes the paper cassette container 4, the roller 313 rotates and can slide and store the bottom surface of the main body 30. Further, when the user pulls out the paper cassette container 4, the roller 313 rotates and the bottom surface of the main body 30 can be slid and pulled out from the main body 30, and the user can replenish the paper P to the paper cassette container 4.

With the paper P loaded, the middle plate 305 can be lifted up and tilted from the horizontal state of the lowest point as shown in FIGS. 3A and 4 as shown in FIG. 3B. It is a mechanism. The middle plate 305 is lifted up by the rotation of the lifter motor 310, and can be lifted up to a higher position by lengthening the driving time, and the paper surface of the loaded paper P can be brought closer to the paper feed roller 8.

The drive torque of the lifter motor 310 is transmitted to the middle plate 305 via the motor gear 312 on the motor shaft and the gear 301 fixed to the main body 30, and further via the fan gear 302 fixed to the middle plate 305. The lifted middle plate 305 has a mechanism that cannot be reset to the horizontal state of the lowest point as shown in FIGS. 3A and 4 unless the paper cassette container 4 is pulled out from the main body 30. By pulling out the paper cassette container 4, the engagement between the fan gear 302 and the gear 301 fixed to the main body 30 is released, and the engagement can be reset. However, the middle plate 305 cannot be reset by the lifter motor 310 or other driving parts. Although not shown, the lifter motor 310 can lift up the middle plate of the lower paper cassette container by rotating it in the direction opposite to the lift-up. In the reset state, as shown in FIG. 3A, the paper presence / absence detection flag 308 does not touch the paper P, so that the paper presence / absence detection sensor 311 is in the OFF state in which the paper P is not detected. ..

Further, the remaining amount detection flag 303 is fixed to the middle plate 305, and the remaining amount detection flag 303 rotates with the lift-up of the middle plate 305 like the fan gear 302. When the lift-up of the middle plate 305 exceeds a predetermined height and the remaining amount detection flag 303 enters the detection area of the remaining amount detection sensor 304, the remaining amount detection sensor 304 is in the ON state of the detection state.

The paper feed roller 8 has a mechanism that moves in the vertical direction. As shown in FIG. 3B, when the paper feed roller 8 is pushed up by the lift-up of the middle plate 305 and the paper feed roller 8 is lifted, the height of the paper surface of the paper P is increased. The paper height detection sensor 307 to be detected is in the ON state of the detection state. At this time, the paper feed roller 8 is in a position where the paper P can be fed.

When the paper presence / absence detection flag 308 is pushed upward by the paper P when the middle plate 305 is lifted up as shown in FIG. 3B, the paper presence / absence detection sensor 311 enters the detection area of the paper presence / absence detection sensor 311. The detected ON state is set. Even if the middle plate 305 is lifted up when the paper P is not on the middle plate 305, the middle plate 305 has a hole so that the paper presence / absence detection flag 308 passes through without contacting the middle plate 305. Therefore, when the paper P is not on the middle plate 305, the paper presence / absence detection flag 308 passes through the middle plate 305 when the middle plate 305 is lifted up, the paper presence / absence detection flag 308 is not pushed upward, and the paper presence / absence detection sensor 311 Since it does not enter the detection area, it is turned off.

The paper size detection sensor 309 is a push switch having a plurality of pressing portions 318 attached to the main body 30, and is located at the rear end of the paper in the paper transport direction or in the paper transport direction with respect to the loaded paper P in the paper feed cassette container 4. It is arranged at a position facing the paper size detection sensor pressing member 316 that operates in conjunction with the regulation plate 317 that regulates the orthogonal paper width directions. FIG. 5 shows a state of the pressing portion 318 of the paper size detecting sensor 309 pressed by the paper size detecting sensor pressing member 316. The state of FIG. 5 is a state in which only the pressing portion 318 (d) of FIG. 6 is not pressed. When the paper cassette container 4 is stored in the main body 30, the paper size detection sensor 309 is pressed by one of the plurality of pressing portions 318 by the paper size detection sensor pressing member 316, and corresponds to the position of the regulation plate 317. The pressing portion 318 to be pressed is determined by the position of the convex portion of the paper size detection sensor pressing member. When the pressing portion is pressed, the paper size is turned on, and the paper size can be detected by combining the ON states of the plurality of pressing portions 318. FIG. 7 shows a combination of the state of the pressing portion 318 and the detection state. In (1), all the pressing portions 318 are turned off, and the state in which the paper cassette container 4 is pulled out is detected in the control unit 200. (3) to (8) and (10) to (15) are states in which various paper sizes are detected, and the detection states of (2), (9) and (16) are not set.

Further, since the paper size detection sensor 309 is configured so that when the paper feed cassette container 4 is stored in the main body 30, any one of the plurality of pressing portions 318 is always pressed, the paper size can be detected and at the same time the paper feed cassette can be detected. It is also possible to detect whether or not the container 4 is stored in the main body 30. When the paper cassette container 4 is not stored in the main body 30, all the pressing portions 318 are turned off. When all the pressing portions 318 are changed from the OFF state to any of the pressing portions 318, it is determined that the paper cassette container 4 is stored in the main body 30 in the control unit 200, and the lifter motor 310 is rotated. As a result, the middle plate 305 in the paper feed cassette container 4 is lifted up.

In the image forming apparatus 100, the regulation plate 317 in the paper feed cassette container 4 is not set at the correct position, and the detection state is not set as shown in (2), (9), and (16) in FIG. When it is in the pressed state, the display on the operation unit 202 has a function to display a message such as "Please set the regulation plate in the correct position" and urge the user to readjust the regulation plate 317. are doing.

Here, a situation that may actually occur when the paper cassette container 4 of the image forming apparatus 100 is pulled out will be described with reference to FIGS. 8 (a), 8 (b), and 8.

When a paper jam occurs in the image forming apparatus 100, the paper may be stopped as shown in FIG. 8A. In that case, the display unit of the operation unit 202 indicates the position of the paper stopped in the image forming apparatus 100, the paper processing procedure, and the like, and the user removes the paper from the image forming apparatus 100 based on the procedure. When the paper P1 is pulled out to remove the paper P1 while being sandwiched between the transport roller 314 and the separation roller 315, the paper P1 is in the direction of pulling out the paper cassette container 4. It may stay in that position without moving.

In such a case, when the paper cassette container 4 is completely pulled out from the main body 30 (the paper cassette container 4 is not separated from the main body 30), the paper P1 is a paper cassette as shown in FIG. 8 (b). Drop out of container 4. Since the dropped paper P1 is located behind the paper feed cassette container 4 that has been pulled out, it cannot be easily visually recognized from the pull-out direction of the paper feed cassette container 4.

When the paper cassette container 4 is returned to the main body 30 in that state, the paper P1 is pushed into the back side of the main body 30 by the paper cassette container 4. In that case, normally, the paper size detection sensor pressing member 316 normally presses the plurality of pressing portions 318 of the paper size detection sensor 309, but the paper P1 pushed into the back side of the paper cassette container 4 unintentionally presses the paper size detection sensor 309. Since the unit 318 is pressed, a display such as "Please set the regulation plate in the correct position" is displayed on the display unit on the operation unit 202. The user who sees the display pulls out the paper cassette container 4 again in order to set the regulation plate 317 in the correct position.

Normally, at this point, the plurality of pressing portions 318 of the paper size detection sensor 309 are not pressed, but when the pressing portion 318 is pressed by the paper P1 pushed into the back side of the main body 30. There is.

Here, a method of determining that the paper P1 in the above situation is pushed into the back side of the paper cassette container 4 and further presses the pressing portion 318 of the paper size detection sensor 309 will be described.

As described above, as shown in FIG. 8B, the paper P1 is dropped from the paper feed cassette container 4 and the paper feed cassette container 4 is returned to the main body 30, and the paper P1 is transferred to the paper feed cassette container 4 by the paper feed cassette container 4. The description will be given from the time point after being pushed into the back side of 4. The unintended pressing portion 318 is pressed by the paper P1. For example, it is assumed that the state of (16) in FIG. 7 (a state in which the pressing portions 318 (a), (b), (c), and (d) are all pressed). Then, in the control unit 200, it is detected that the paper cassette container 4 is stored in the main body 30, and the middle plate 305 in the paper cassette container 4 is lifted up by rotating the lifter motor 310. When the middle plate 305 is lifted up and the paper P is set in the paper cassette container 4, the paper presence / absence detection flag 308 is pushed upward by the paper P as shown in FIG. 3B, and the paper presence / absence detection sensor 311 Detects the paper P and turns on. Here, since all the pressing units 318 of the paper size detection sensor 309 are pressed, a display such as "Please set the regulation plate at the correct position" is displayed on the display unit on the operation unit 202.

The user who sees the display pulls out the paper cassette container 4 again in order to set the regulation plate 317 in the correct position. At this time, the middle plate 305 in the paper cassette container 4 is reset by pulling out the paper cassette container 4 as described above so that the engagement between the fan gear 302 and the gear 301 fixed to the main body 30 is released. As a result, as shown in FIG. 3A, the lowest point becomes horizontal. In this state, the paper presence / absence detection flag 308 pushed up by the paper P is lowered, and the paper presence / absence detection sensor 311 does not detect the paper P, so that the state is turned off. Only when a message such as "Please set the regulation plate in the correct position" is displayed on the display unit on the operation unit 202, the paper presence detection sensor 311 is turned off in the control unit 200. It is detected that the paper cassette container 4 is pulled out from the main body 30. Despite detecting that the paper cassette container 4 has been pulled out in this way, when any of the pressing portions 318 of the paper size detection sensor 309 is pressed, the paper P1 is pushed into the back side of the main body 30. Judge that

The above contents will be described with reference to the flowcharts of FIGS. 9 and 10.

FIG. 9 is a flowchart showing a start-up operation of the image forming apparatus 100.

When the power of the image forming apparatus 100 is turned on, the CPU 201a in the control unit 200 instructs S900 to perform an initial operation for each control unit. For example, the motor control unit 207 rotates each motor 212, and the high voltage control unit 205 controls the high voltage unit 206. At the same time, the operation of the paper cassette container 4 is performed in S901. By the sensor IF209, one of the pressing portions 318 of the paper size detection sensor 309 is in the ON state (detects the state in which the paper feed cassette container 4 is stored in the main body 30), and the paper presence / absence detection sensor 311 is in the OFF state (paper). If none is detected), the motor control unit 207 rotates the lifter motor 310 to lift up the middle plate 305. After the above operation, it is confirmed whether an error or an alarm has occurred in S902, and if it occurs (Y in S902), an error or an alarm is displayed on the display unit of the operation unit 202 in S903. If no error or alarm occurs (N in S902), the image forming apparatus start-up operation ends, and the image forming apparatus 100 goes into the standby state.

FIG. 10 is a flowchart showing the operation of the paper cassette container 4.

It is confirmed in S1000 whether the image forming apparatus 100 of FIG. 9 is in the start-up operation, and if it is in the start-up operation (Y in S1000), the process proceeds to S1003. If not, the paper size detection sensor 309 is in S1001. Check the state of the pressing portion 318 of. Next, in S1002, it waits (N in S1002) for all the pressing portions 318 to be in the OFF state (state of (1) in FIG. 7). Here, it is confirmed whether or not all the pressing portions 318 are turned off, and it is confirmed whether or not the paper cassette container 4 is pulled out from the main body 30. When all the pressing portions 318 are turned off (Y in S1002), wait until any of the pressing portions 318 is turned ON in S1003 (N in S1003).

Here, it is confirmed whether any one of the pressing portions 318 is turned ON, and it is confirmed whether the paper cassette container 4 is stored in the main body 30. When the pressing portion 318 is in the ON state (Y in S1003), the lifter motor 310 is rotated in S1004 to lift up the middle plate 305. After that, in S1005, it is confirmed whether the pressing portion 318 is in the detection state of a predetermined size as shown in FIGS. 7 (3) to (8) and (10) to (15). As a result, when the predetermined size detection state is reached (Y in S1005), the paper cassette container operation is completed and the predetermined size detection state is not reached (N in S1005) ((2 in FIG. 7). ) Or (9) or (16)), the CPU201a instructs the display unit of the operation unit 202 to display "Please set the regulation plate in the correct position" in S1006. After that, it waits until the paper presence / absence detection sensor 311 changes from the ON state to the OFF state by S1007 (N in S1007). Here, it is confirmed whether the paper presence / absence detection sensor 311 is changed from the ON state to the OFF state, and it is confirmed whether the paper cassette container 4 is pulled out from the main body 30. The paper presence / absence detection sensor 311 determines whether or not the paper feed cassette container 4 has been pulled out from the main body 30 only when the pressing portion 318 does not reach the predetermined size detection state in S1005. When the paper presence / absence detection sensor 311 changes from the ON state to the OFF state (Y in S1007), it is confirmed in S1008 whether any of the pressing portions 318 is in the ON state.

Here, it is confirmed whether or not any of the pressing portions 318 is in the ON state, and it is confirmed whether or not the paper P is on the back side of the paper feed cassette container 4. When any of the pressing units 318 is not in the ON state (N in S1008), it returns to S1003 and waits for any of the pressing units 318 to be in the ON state, and when any of the pressing units 318 is in the ON state (N). In S1008, Y) indicates the flow of the paper cassette container operation by instructing the CPU 201a to display "there is a possibility of foreign matter such as paper on the back side of the paper cassette container 4" on the display unit of the operation unit 202. To finish. It should be noted that this flow is always carried out in a state where the image forming apparatus 100 is operating regardless of the startup operation.

In the above configuration, the method of determining that the user may have paper on the back side of the paper cassette container 4 is that the pressing portion 318 of the paper size detection sensor 309 is not in the predetermined size detection state (FIG. 7). When it is detected that the states (2), (9), and (16) have been reached), the paper presence / absence detection sensor 311 detects whether or not the paper cassette container 4 is pulled out from the main body 30. When it is detected that the paper cassette container 4 has been pulled out from the main body, if any of the pressing portions 318 is in the ON state, there is a possibility that the paper is present on the back side of the paper cassette container 4. to decide. In this case, for an image forming device that uses a paper size detection sensor as a sensor to determine whether or not the paper cassette container is stored in the main body, the paper is jammed in the back side of the paper cassette container and the paper size is detected. This is effective when the sensor is no longer in the predetermined detection state.

When the paper size detection sensor is not in the predetermined detection state, a display prompting the user to set the regulation plate in the correct position is displayed on the display unit on the operation unit. After that, if the pressing part of the paper size detection sensor is pressed even though the paper cassette container is pulled out from the main body, the contents displayed on the display unit until then are displayed on the paper cassette container. Switch to the content that there may be paper on the back side of. By doing so, the user can immediately remove the paper in a position that is usually not easily noticed, and the paper cassette container can also be used, so that downtime can be shortened.

Although the paper size detection sensor described above has been described with a push switch, a sensor having a plurality of photo interrupters may be used.

P paper, P1 paper jammed in the paper cassette container 4, 4 paper cassette container,
8 Paper feed roller, 202 operation unit, 207 motor control unit, 301 gear,
302 fan gear, 304 remaining amount detection sensor, 305 middle plate,
307 Paper height detection sensor, 309 Paper size detection sensor,
310 Lifter Motor, 311 Paper Presence Detection Sensor, 312 Motor Gear,
313 Paper cassette container drawer mechanism, 314 transport roller, 315 separation roller,
316 Paper size detection sensor pressing member, 317 regulation plate, 318 pressing part

Claims (2)

A regulation plate that is movably provided in a paper cassette container that can set a plurality of sheets of paper and is in contact with the paper set in the paper cassette container.
A paper size detection unit having a plurality of detection units and detecting the size of the paper loaded in the paper cassette container based on the detection results of the plurality of detection units.
A movable member that operates in conjunction with the movement of the regulation plate, has a plurality of convex portions formed, is installed at the position of the paper cassette container facing the paper size detection unit, and is detected by the paper size detection unit.
When any one of the plurality of detection units of the paper size detection unit is detected, the determination unit for determining that the paper cassette container is set and the determination unit
A control unit that lifts up and controls the paper inside the paper cassette container when the determination unit determines that the paper cassette container is set.
A paper presence / absence detection unit that detects the presence / absence of paper loaded in the paper cassette container, and
A notification unit that notifies the status of the paper cassette container and
A notification instruction unit that instructs the notification unit to notify a predetermined notification content, and
In the image forming apparatus having
When the paper size detection unit is in a predetermined detection state, the notification instruction unit instructs the notification unit to notify the first notification content, and the paper size detection unit is in the predetermined detection state. In the state, after the paper presence / absence detection unit is in the non-detection state, if any of the plurality of detection units of the paper size detection unit has detected, the notification unit is instructed to switch to the second notification content. An image forming apparatus characterized in that. The first notification content urges the regulation plate to be set in the correct position, and the second notification content indicates that foreign matter may be present on the back side of the paper feed cassette container. The image forming apparatus according to claim 1.