JP6706659B2 - Feeding device and image forming system - Google Patents

Description

The present invention relates to a sheet feeding device capable of feeding a sheet and an image forming system.

A feeding device such as a side paper deck that can be separated from an image forming apparatus is known. For example, when removing a jammed sheet, the feeding device is separated from the image forming apparatus. After separating the sheets and removing the sheets, when connecting the sheet feeding device to the image forming apparatus, the direction in which the sheet feeding device is moved and the direction in which the sheet is conveyed from the sheet feeding device to the image forming apparatus should be the same direction. For example, a strong force acts on the sheet in the conveying direction. As a result, the sheet may enter the pair of rollers that convey the sheet by the feeding device.

In some cases, the sheet feeding device is configured so that the sheet storage unit can be pulled out in a direction perpendicular to the conveying direction when replenishing the sheet. Here, if the sheet storage unit is pulled out in a state where the sheet has entered the roller pair, the sheet is pulled out while being caught by the roller pair, and as a result, the sheet is torn.

In Patent Document 1, in order to solve such a problem, when the sheet storage cassette is detached from the main body, the sheet feeding path from the sheet storage cassette to the roller pair is cut off, and the sheet storage cassette is attached to the main body. A configuration for releasing the interruption of the sheet feeding path is described.

JP, 2014-105070, A

However, in Japanese Patent Application Laid-Open No. 2014-105070, although it is possible to prevent the sheet from entering the roller pair when the sheet storage cassette is attached to the main body, the provision of the dedicated mechanism causes the apparatus to be complicated and the cost to increase. ..

In view of such conventional problems, an object of the present invention is to provide a feeding device and an image forming system that prevent a sheet from entering a roller pair when a sheet storage unit is attached to a main body with a simple configuration. The purpose is to provide.

In order to solve the above problems, a feeding device according to the present invention is a feeding device that feeds a sheet to a device that is a feeding destination, and includes a stacking unit that is arranged so as to be vertically movable and stacks the sheet, A sheet storage unit movable to a first position accommodated inside the feeding device and a second position pulled out from the inside of the feeding device, and loaded on the stacking unit. A transport unit including a pair of rollers for transporting a sheet supplied from a predetermined height among the sheets , wherein the sheet storage unit is in the first position and the second position. A connection state in which the conveyance unit provided inside the feeding device, the feeding device and the device serving as the feeding destination are connected so that sheets can be fed, and the feeding device and the feeding destination The attachment/detachment detection unit that detects a separation state in which the apparatus is separated, the sheet detection unit that detects the presence or absence of the sheet on the stacking unit, and the attachment/detachment state in the state where the sheet storage unit is in the first position. A position where the sheet on the stacking unit is at the predetermined height in response to the sheet detecting unit detecting the presence of the sheet when the detecting unit detects the connected state from the separated state. To the stacking unit in response to the sheet detecting unit detecting the presence of a sheet when the stacking unit is moved to And a control unit that moves the stacking unit to a position where the sheet is lower than the predetermined height and higher than a lower limit position in a range in which the stacking unit can move up and down.

According to the present invention, it is possible to prevent the sheet from entering the roller pair when the sheet feeding device is connected to the sheet feeding device with a simple configuration.

FIG. 3 is a diagram showing a configuration of an image forming apparatus. It is a figure which shows the structure of a feeding deck part. It is a figure which shows the block configuration of the control system in a feeder. 8 is a flowchart of stacking unit drive control when the feeding deck unit is separated. FIG. 6 is a schematic view showing a state in which the sheet surface is lowered when the feeding deck portion of the embodiment of the present invention is separated.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the present invention according to the claims, and all combinations of the features described in the present embodiments are not necessarily essential to the solving means of the present invention. .. In addition, the same reference numerals are given to the same components, and the description thereof will be omitted.

<Schematic configuration of image forming apparatus>
FIG. 1 is a diagram showing a configuration of an image forming system 100 according to this embodiment. The image forming system 100 includes an apparatus main body 1 and a feeding deck 2 (feeding device). FIG. 1A shows a state (connection state) in which the feeding deck 2 is attached to the apparatus main body 1, and FIG. 1B shows a state in which the feeding deck 2 is separated from the apparatus main body 1 ( (Separated state). When the feeding deck 2 is attached to the apparatus body 1, the feeding deck 2 and the apparatus body 1 are connected via the feeding path 41. Further, in the state where the feeding deck 2 is separated from the apparatus main body 1, for example, the user can remove the sheet S that has caused the jam.

The apparatus main body 1 serves as an image forming unit that forms an image on a recording medium, and includes a photosensitive drum 10, a laser scanner 11, a mirror 12, a charger 13, a developing device 14, a transfer roller 15, and a cleaner 16. Is equipped at the top. The charger 13 uniformly charges the surface of the photosensitive drum 10. The laser scanner 11 irradiates the photosensitive drum 10 charged by the charger 13 with a pattern of image data to be image-formed through the mirror 12. As a result, an electrostatic latent image is formed on the photosensitive drum 10. The developing device 14 develops the electrostatic latent image formed by the laser scanner 11 into a toner image. The transfer roller 15 transfers the toner image visualized on the surface of the photosensitive drum 10 to the sheet S. The cleaner 16 removes the toner remaining on the photosensitive drum 10 after transferring the toner image. Although FIG. 1 shows a configuration based on the electrophotographic method, another recording method such as an inkjet recording method may be adopted in the apparatus main body 1.

On the downstream side of the image forming unit in the sheet transport direction, a transport unit 17 for transporting the sheet S on which the toner image is transferred, and the toner image on the sheet S transported by the transport unit 17 are fixed as a permanent image. The fixing device 18 is provided for the purpose. Further, a discharge roller 19 for discharging the sheet S having the toner image fixed by the fixing device 18 from the apparatus main body 1 is provided on the downstream side of the fixing device 18. A discharge sheet stack tray 20 for receiving the sheets S discharged by the discharge rollers 19 is provided outside the upper portion of the apparatus main body 1.

The cassette feeding trays 30a to 30d are provided so as to be positioned at the uppermost stream in the sheet feeding path, and can store a predetermined number of sheets S. Cassette feed roller pairs 31a to 31d are provided downstream of the cassette feed trays 30a to 30d to pick up the uppermost sheet S from the sheet bundle. The picked-up sheet S is conveyed to the vertical conveyance path 33 by the pull-out roller pairs 32a to 32d. A manual feed unit 30e is provided on the side surface of the apparatus body 1. A manual feed roller pair 31e is provided downstream of the manual feed unit 30e to pick up the sheet S. The picked-up sheet S is conveyed to the vertical conveyance path 33.

The feeding deck 2 is configured to be capable of accommodating a relatively large capacity sheet S such as a unit of 1000 sheets, and in the present embodiment, is configured to be connectable to a lower portion of the manual feeding unit 30e. The feeding deck 2 conveys the uppermost sheet S from the stacked sheet bundle until the pickup roller 31f nips the sheet S to the feeding roller pair 31g. The pair of feeding rollers 31g separates the sheets S and feeds the sheets S one by one to the apparatus main body 1 side (downstream side) serving as the feeding destination. As described above, since the stacking space of the sheets S occupies a large space in the feeding deck 2, the feeding portion of the sheets S picked up by the pickup roller 31f is fed to the feeding roller pair 31g as it is due to its structure. Located at a possible height.

The sheet S is conveyed to the vertical conveyance path 33 by the pull-out roller pair 32a. The registration roller pair 34 located at the most downstream position of the vertical transport path 33 performs skew feed correction of the sheet S, timing of image writing and sheet transport. Further, as shown in FIG. 1B, when the feeding deck 2 is separated from the apparatus main body 1 for jam clearance or the like, in FIG. 1A, the attachment/detachment stored in the feeding deck 2 is removed. The feeding deck 2 moves along the rail 35 so as to be separated from the apparatus main body 1.

<Schematic structure of feeding deck>
FIG. 2 is a schematic configuration diagram of the feeding deck 2. The feeding deck 2 includes a sheet storing unit 3 (sheet storing unit) that stores the sheet S, a pickup roller 31f (pickup unit), a pair of feeding rollers 31g (conveying unit), and an attachment/detachment sensor 40.

The sheet storage unit 3 housed inside the feeding deck 2 is disposed inside the sheet storage unit 3 so as to be able to move up and down, and includes a stacking unit 36 (stacking unit) on which sheets S can be stacked and a stacking unit 36 (on the stacking unit). A sheet presence/absence sensor 37 (sheet detection unit) for detecting the presence/absence of the sheet S, an upper surface detection sensor 38 (sheet height detection unit) for detecting the upper surface of the stacked sheets S, and a maximum when the stacking unit 36 descends The lower limit detection sensor 42 which detects a lower limit is included. The sheet storage unit 3 is configured to be pulled out in a direction intersecting the feeding direction from a state of being accommodated inside the feeding deck 2 by a pull-out rail 43. The sheet presence/absence sensor 37 and the upper surface detection sensor 38 are configured to have, for example, a flag portion (not shown). The sheet presence sensor 37 is, for example, a distance measuring sensor. The detection point of the sheet presence/absence sensor 37 is provided below the detection point of the upper surface detection sensor 38, and a concave portion for the presence/absence of the sheet S to be detected by the sheet presence/absence sensor 37 ( For example, a groove) is provided. The upper surface detection sensor 38 detects the uppermost surface including the stacked sheets S when the sheets S are stacked on the stacking unit 36. On the other hand, when the sheets S are not stacked on the stacking unit 36, the stacking surface of the stacking unit 36 is detected.

The stacking unit 36 on which the sheets S are stacked can be moved in the H direction (elevating direction) in FIG. 2 by an elevating mechanism (not shown) that can lift the stacking unit 36. The stacking unit 36 is controlled by the detection results of the sheet presence sensor 37 and the upper surface detection sensor 38 so that the uppermost surface of the stacked sheet bundle is always at an appropriate height for feeding.

An attachment/detachment sensor 40 is provided on the feeding deck 2. The attachment/detachment sensor 40 (detection unit) is connected to the feeding deck 2 via the feeding path 41 for feeding the sheet S to the apparatus main body 1 or separated from each other, that is, in the connected state. It is detected whether it is present or in the separated state. The attachment/detachment rail 35 has, for example, a mechanism for expanding and contracting. In the present embodiment, the attachment/detachment rail 35 is housed inside the feeding deck 2 when mounted on the apparatus body 1. Further, the attachment/detachment rail 35 may be configured to be housed inside the apparatus body 1 when being mounted on the apparatus body 1.

As described above, due to the structure, the sheet S picked up by the pickup roller 31f is positioned at a height at which it can be fed as it is to the feeding roller pair 31g. That is, when the feeding deck 2 is mounted on the apparatus body 1, the direction in which the feeding deck 2 is moved and the direction in which the sheet S is conveyed from the feeding deck 2 to the apparatus body 1 are substantially the same. The heights of the feeding path 41 and the upper surface of the seat are substantially the same. Therefore, if a strong force acts on the sheet S in the conveyance direction due to the momentum when the feeding deck 2 is mounted on the apparatus main body 1, the sheet S enters the feeding roller pair 31g of the feeding deck 2. Sometimes. Further, the sheet S may enter the apparatus body 1 side via the pair of feeding rollers 31g and straddle the sheet. In that case, even if the user releases the jam and attaches the feeding deck 2 to the apparatus main body 1, the jam occurs. Furthermore, if the sheet storage unit 3 is pulled out in such a state, the sheet S at the jam position is torn.

Therefore, in this embodiment, when the feeding deck 2 is separated from the apparatus main body 1, the elevating mechanism is controlled so as to lower the upper surface position of the sheet S. With such a configuration, even when the sheet S is biased in the mounting direction, that is, in the direction of the feeding path 41 when the feeding deck is mounted on the main body, the sheet S is prevented from entering the feeding roller pair 31g. be able to.

FIG. 3 is a diagram showing a block configuration of a control system of the feeding deck 2. FIG. 3 shows the apparatus main body 1 and the feeding deck 2. The feeding deck 2 includes a display unit 47 (notification unit). The display unit 47 includes, for example, an operation panel, and is configured above the feeding deck 2. The display unit 47 displays various user interface screens such as device information, setting screens, and job information. The display unit 47 includes, for example, hard keys, and receives job execution instructions and function setting operations from the user. The apparatus main body 1 of FIG. 4 has a controller including a CPU, and controls the apparatus main body 1 comprehensively based on a job or the like. For example, the CPU of the apparatus main body 1 mutually communicates with the CPU 45 of the feeding deck 2 to control a series of processes from feeding to image formation on a recording medium.

The controller 60 of the feeding deck 2 includes a CPU 45 (control unit), a ROM 61, and a RAM 62. For example, the CPU 45 reads the program stored in the ROM 61 into the RAM 62 and executes the program, whereby the controller 60 controls the operation of the feeding deck 2. For example, the CPU of the apparatus body 1 transmits a feeding request to the CPU 45 of the feeding deck 2 at the feeding timing when executing a job, and the CPU 45 receives the feeding request from the CPU of the apparatus body 1, The feeding deck 2 is controlled so that the feeding operation is performed on the apparatus main body 1. Further, each component of the controller 60 is connected to each other via a bus 63, and the bus 63 functions as a data communication path between various components.

Detection signals from the sheet presence/absence sensor 37, the upper surface detection sensor 38, the attachment/detachment sensor 40, and the lower limit detection sensor 42 are transmitted to the CPU 45. When raising the loading section 36, the CPU 45 raises the loading section 36 until the upper surface detection sensor 38 detects the upper surface. The height of the stacking unit 36 when the upper surface detection sensor 38 detects the upper surface is such that the height of the feeding path 41 and the height of the upper surface of the sheet are substantially the same, and the sheet S can be fed to the apparatus main body 1. It is high. Here, when the sheet S is stacked on the stacking unit 36, the sheet presence sensor 37 is turned on by the sheet S, and the presence of the sheet is detected. On the other hand, when the sheet S is not stacked on the stacking unit 36, the sheet presence sensor 37 is turned off, so that no sheet is detected. When the sheet presence sensor 37 detects that there is no sheet, the CPU 45 displays a message prompting the supply of the sheet S on the display unit 47.

When the attachment/detachment sensor 40 detects that the apparatus body 1 and the feeding deck 2 are separated, the CPU 45 lowers the stacking unit 36 by a predetermined amount. After that, when the attachment/detachment sensor 40 detects that the feeding deck 2 is attached to the apparatus body 1, the CPU 45 raises the stacking unit 36 to a height at which the sheet S can be fed to the apparatus body 1. Details of the control when the feeding deck is attached or detached will be described later.

Further, the CPU 45 drives various motors 53 on the conveyance path of the sheet S including the feeding path 41 via the motor driver 52 connected to the input/output interface (I/O) 51, and drives the various rollers. To do. Here, the various rollers include a pickup roller 31f and a feeding roller pair 31g.

<Flow chart of lifting control of loading section>
FIG. 4 is a flow chart showing a procedure of processing for raising and lowering the stacking unit when the feeding deck 2 is separated from the apparatus main body 1. According to the processing of FIG. 4, when the feeding deck 2 is attached to the apparatus main body 1, even if the sheet S is urged in the feeding path direction, the sheet S enters the feeding nip portion of the feeding roller pair 31g. Can be prevented. The process of FIG. 4 is realized, for example, by the CPU 45 reading the program stored in the ROM 61 into the RAM 62 and executing the program. The CPU 45 starts the process of FIG. 4 when the power of the device body 1 is turned on, for example.

In S101, the CPU 45 outputs the output signal of the attachment/detachment sensor 40 in order to determine whether or not the feeding deck 2 is separated from the apparatus main body 1 in a state where the feeding deck 2 is inserted into the sheet storage portion 3. To detect. When the output of the attachment/detachment sensor 40 is ON, the CPU 45 determines that the feeding deck 2 is attached to the apparatus main body 1, and repeats the processing of S101. On the other hand, when the output of the attachment/detachment sensor 40 is off in S101, the CPU 45 determines that the feeding deck 2 is separated from the apparatus main body 1, and proceeds to the processing of S102.

In S102, the CPU 45 detects the output signal of the upper surface detection sensor 38 in order to determine whether the height of the upper surface of the stacking unit 36 or the sheet S is a height at which the upper surface of the stacking unit 36 or the sheet S can be fed to the apparatus main body 1. When the output of the upper surface detection sensor 38 is OFF, the CPU 45 determines that the height of the upper surface of the stacking unit 36 or the sheet S is lower than the height at which the stacking unit 36 can be fed to the apparatus body 1, and determines the height of the stacking unit 36. The process proceeds to S110 while maintaining the same. On the other hand, in S102, when the output of the upper surface detection sensor 38 is on, the CPU 45 determines that the height of the upper surface of the stacking unit 36 or the sheet S is a height at which it can be fed to the apparatus main body 1, and proceeds to S103. ..

In S103, the CPU 45 detects the output signal of the sheet presence sensor 37 in order to determine whether or not the sheets S are stacked. When the output of the sheet presence/absence sensor 37 is ON, the CPU 45 determines that the sheets S are stacked, and proceeds to S109. On the other hand, when the output of the sheet presence sensor 37 is off, the CPU 45 determines that the sheets S are not stacked and proceeds to S104.

In S104, the CPU 45 starts the descent of the stacking unit 36. In S105, the CPU 45 detects the output signal of the lower limit detection sensor 42 in order to determine whether the stacking unit 36 has reached the lowest limit position. When the output of the lower limit detection sensor 42 is off, the CPU 45 determines that the stacking unit 36 has not reached the lower limit yet, and returns to the process of S104. On the other hand, when the output of the lower limit detection sensor 42 is on, the CPU 45 determines that the stacking unit 36 has reached the lower limit, the process proceeds to S106, the descent of the stacking unit 36 is stopped, and the process proceeds to S107.

In S107, the CPU 45 displays a message prompting the user to replenish the sheet S on the display unit 47. Thereafter, in S108, the CPU 45 determines whether or not the sheet S has been replenished. When determining that the supply of the sheet S is not completed, the CPU 45 repeats the process of S108. On the other hand, when determining that the supply of the sheet S is completed, the CPU 45 returns to the process of S102. Whether or not the replenishment of the sheet S is completed is determined based on, for example, whether or not the sheet storage unit 3 is inserted into the feeding deck 2.

In addition, in S106, after the CPU 45 stops the lowering of the stacking unit 36, the CPU 45 may raise the stacking unit 36 and proceed to S107. The position of the stacking unit 36 at this time is the position where the stacking unit 36 is lowered by a predetermined amount in S109. As a result, when the user receives the sheet absence notification in S107 and supplies the sheet S, the CPU 45 is raising the stacking unit 36. Therefore, even when the user feeds the sheet S until the upper surface reaches the feedable position and the process of FIG. 4 continues and proceeds to S102 to S103 to S109, the stacking unit 36 is lowered by a predetermined amount. be able to.

In S109, the CPU 45 lowers the stacking unit 36 by a predetermined amount, and proceeds to S110. When the stacking unit 36 is lowered by a predetermined amount in S109, the CPU 45 displays, for example, a message "The feeding deck 2 can be connected to the apparatus main body 1" on the display unit 47. In S110, the CPU 45 outputs the output signal of the attachment/detachment sensor 40 in order to determine whether or not the feeding deck 2 is attached to the apparatus main body 1 when the feeding deck 2 is inserted into the sheet storage unit 3. To detect. When the output of the attachment/detachment sensor 40 is off, the CPU 45 determines that the feeding deck 2 is separated from the apparatus main body 1, and repeats the processing of S113. On the other hand, when it is determined that the output of the attachment/detachment sensor 40 is off, the CPU 45 determines that the feeding deck 2 is attached to the apparatus main body 1, and proceeds to the processing of S111.

In S111, the CPU 45 starts raising the stacking unit 36. In S112, it is determined whether or not the height of the upper surface of the stacking unit 36 or the sheet S is a height at which the sheet can be fed to the apparatus main body 1 by the same process as S102. When the CPU 45 determines that the upper surface has not reached the feedable height, the CPU 45 returns to the processing of S111. When the CPU 45 determines that the upper surface has reached the height at which it can be fed, the CPU 45 proceeds to S113, stops the lifting of the stacking unit 36, and then ends the processing of FIG.

By the above-described processing, it is possible to prevent the sheet S from entering the pair of feeding rollers 31g when the sheet D is mounted on the apparatus main body 1 from the state where the feeding deck 2 is separated from the apparatus main body 1. ..

<Structure when the loading section is lowered by the process of S109>
FIG. 5A is a diagram showing a state in which the upper surface of the sheets S stacked on the feeding deck 2 is at a height at which the sheets can be fed, and FIG. 5B shows the upper surface of the sheets S stacked on the feeding deck 2. It is the figure which showed the state which descended from the height which can be fed by the predetermined amount by the process of S109 of FIG.

In the state of FIG. 5A, the height of the upper surface of the sheet S and the height of the feeding path 41 on the stacking unit 36 side are substantially the same. Therefore, when the feeding deck 2 is vigorously attached to the apparatus body 1, the sheet bundle is urged in the direction of the apparatus body 1, and the sheet S at the height of the feedable position P is on the feeding path 41. The feeding roller pair 31g may be thrust into the feeding nip portion.

On the other hand, in the state of FIG. 5B, the height of the upper surface of the sheet S is at a position lower than the feedable position P by a predetermined amount L. At a position where the sheet L on the upper surface is lowered by the predetermined amount L, even if the feeding deck 2 is vigorously attached to the apparatus main body 1 and the sheet bundle is urged toward the apparatus main body 1, the sheet S on the upper surface is the sheet storage unit 3 This is a position where it does not enter the feeding nip portion of the feeding roller pair 31g.

That is, in the present embodiment, when the feeding deck 2 is separated from the apparatus main body 1, the stacking unit 36 is lowered by a predetermined amount L to prevent the feeding roller pair 31g from entering the feeding nip portion. .. In this embodiment, the predetermined amount L for lowering the stacking unit 36 is, for example, 3 cm, and the position lowered by 3 cm in the downward direction is the predetermined position. It should be noted that the predetermined amount L may be arbitrarily determined according to the basis weight of the sheet S and the friction coefficient within a range that does not enter the feeding nip portion of the feeding roller pair 31g.

According to this embodiment, when the feeding deck 2 is separated from the apparatus main body 1, the CPU 45 lowers the height of the upper surface of the stacked sheets by a predetermined amount from the feedable position. Therefore, it is possible to prevent the sheet S from being urged by the momentum when the feeding deck 2 is attached to the apparatus main body 1 and entering the sheet S into the feeding nip portion of the feeding roller pair 31g.

Further, according to the present embodiment, the feeding deck 2 is mounted on the apparatus body 1 in a state where the feeding deck 2 is separated from the apparatus body 1 and the height of the upper surface of the stacked sheets S is lowered by a predetermined amount. Then, the CPU 45 raises the height of the upper surface of the sheet S to the supply possible position. Therefore, even if the height of the upper surface of the sheet S is lowered by a predetermined amount, the height of the upper surface of the sheet S is higher than that of the feeding deck 2 when the feeding deck 2 is mounted on the apparatus main body 1. The sheet S can be supplied to the apparatus body. Furthermore, according to the present embodiment, when it is detected that the sheets S are not stacked when the feeding deck 2 is separated from the apparatus main body 1, the CPU 45 sets the height of the stacking unit 36 to a predetermined amount. No lowering to the lowest limit. Therefore, when the sheets S are not stacked, the user can replenish the sheets S with the stacking unit 36 lowered to the lowest limit.

(Other embodiments)
In the above-described embodiment, the CPU 45 lowers the stacking unit 36 to the position of the lower limit detection sensor 42 when the sheet presence sensor 37 is off. However, the application of the present invention is not limited to this. For example, the height between the uppermost surface and the lowermost surface may be defined in advance as a sheet replenishing position for the user to easily replenish the sheets, and the CPU 45 may lower the stacking unit 36 to the sheet replenishing position. In that case, a position detection sensor for detecting that the stacking unit 36 has reached the specified sheet supply position is provided. Then, in such a configuration, S105 in the flowchart of FIG. 4 is a process of determining whether or not the position detection sensor detects that the stacking unit 36 has reached the sheet supply position. The CPU 45 starts the lowering of the stacking unit 36 by the process of S104 during the sheet replenishment, and stops the lowering of the stacking unit 36 by the process of S106 when the sheet replenishment position is detected by the process of S105. With such a configuration, the stacking unit stops at a height at which sheets can be easily supplied, so that sheets can be easily supplied by the user.

Further, a configuration in which a plurality of position detection sensors are provided or a configuration in which the lower limit detection sensor 42 and one or a plurality of position detection sensors are provided at the same time may be adopted. The plurality of position detection sensors may be provided, for example, at a height of 1/4, 2/4, and 3/4 of the height of the uppermost surface from the lowermost limit. At this time, the user operates the operation panel of the display unit 47 so that a desired sheet replenishment position can be selected in advance from the sheet replenishment positions detected by the lower limit detection sensor 42 or the plurality of position detection sensors described above. May be. The CPU 45 starts the descent of the stacking unit 36 by the process of S104, and when the lower limit detection sensor 42 or the position detection sensor corresponding to the height of the selected replenishment position detects the stacking unit 36 in the process of S105, By the process of S106, the lowering of the stacking unit 36 is stopped. With the above-described configuration, the user can select the height of the stacking unit 36 when replenishing sheets from a plurality of heights.

The number of position detection sensors is not limited and may be two or less or four or more. Further, the position of the position detection sensor is not limited to the above example and can be set arbitrarily. For example, by setting the distance from the uppermost surface to the sheet replenishment position to be an integral multiple of the predetermined thickness of the sheet bundle to be replenished, the user can efficiently replenish the sheets.

Further, the feeding deck 2 may have a configuration without a CPU. In that case, the CPU, which is the control means of the apparatus main body 1, controls the stacking unit 36 of the feeding deck 2. Alternatively, the feeding deck 2 includes an ASIC for control, and the ASIC of the feeding deck controls the stacking unit 36 based on a command from the CPU of the apparatus body.

1 Device body 2 Feeding deck 45 CPU
100 image forming system

Claims (9)

A feeding device for feeding a sheet to a device to be a feeding destination,
A stacking unit that is vertically movable and stacks the sheets, and moves to a first position housed inside the feeding device and a second position pulled out from the inside of the feeding device. Possible seat accommodation unit,
Of the sheets stacked on the stacking unit , there is provided a transport unit including a pair of rollers for transporting a sheet supplied from a predetermined height , wherein the sheet storage unit has the first position and the second position. A transport unit provided inside the feeding device in the position ,
Attachment/ detachment for detecting a connection state in which the sheet feeding device and the sheet feeding destination device are connected so that sheets can be fed, and a separated state in which the sheet feeding device and the sheet feeding destination device are separated from each other. A detector,
A sheet detection unit that detects the presence or absence of the sheet on the stacking unit;
In a state where the sheet storage unit is in the first position,
When the attachment/detachment detection unit detects that the sheet is in the connection state from the separated state, the sheet detection unit detects that there is a sheet and the sheet on the stacking unit has the predetermined height. Move the loading unit to
When the attachment/detachment detection unit detects that the connection state is changed to the separated state, the sheet detection unit detects that there is a sheet, and the sheet on the stacking unit is moved to a position higher than the predetermined height. And a control unit for moving the loading unit to a position higher than a lower limit position in a range in which the loading unit can move up and down .
A feeding device characterized by the above. In response to the attachment/detachment detection unit detecting that the detached state has changed to the connected state, the control unit detects that the sheet that is located at a position lower than the prescribed height in the detached state has the prescribed height. The feeding device according to claim 1, wherein the stacking unit is moved so as to: The control unit lowers the stacking unit to a height at which the sheet does not enter a nip formed by the roller pair when the attachment/detachment detection unit detects the separated state. Or the feeding device according to 2. Before SL control unit, the detachable the sheet detecting unit in response to detecting the absence of sheets when the detecting section detects from the connection state became and the separated state, the lower limit position of the loading unit is lowered to the location,
Feeding apparatus according to any one of claims 1 to 3, characterized in that. Wherein when it is detected that there is no sheet by the sheet detection unit, the feeding device according to any one of claims 1 to 4, further comprising notifying unit for notifying that there is no such a sheet, a. When it is detected that there is a sheet on the stacking unit , and the sheet stacked on the stacking unit is not in a position where it can be fed to the device that is the destination, the control unit causes the stacking unit to move. The feeding device according to any one of claims 1 to 5, wherein the height of the feeding device is maintained. Further comprising a sheet height detection unit for detecting the presence or absence of the sheet at the predetermined height,
The control unit, when the sheet accommodating unit is in the first position while the attachment/detachment detection unit is detecting the separated state, causes the sheet height detection unit to detect a sheet at the predetermined height. Moving the loading unit when detected,
The feeding device according to any one of claims 1 to 6, wherein: The feeding device according to claim 1, further comprising a pickup unit that supplies the sheet having the predetermined height among the sheets stacked on the stacking unit to the roller pair of the transport unit. The feeding device according to claim 1,
An image forming apparatus that is an apparatus serving as the feeding destination, and that forms an image on a sheet fed from the feeding apparatus;
An image forming system including.

Images