JP2002274676A - Sheet carrier device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet carrier device compatibly having a cleaning performance and abrasion preventing of a carrier roll while reducing the labor of a service engineer for cleaning the carrier roll. SOLUTION: This sheet carrier device having the carrier roll carrying the sheets by butting on and rotating the sheets is provided with a cleaning member intermittently approaching to/separating from the carrier roll at a prescribed timing to clean the surface of the carrier roll.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a sheet conveying apparatus for conveying a sheet, and more particularly, to an improvement in a cleaning technique of a conveying roll.

[0002]

2. Description of the Related Art There is widely known a sheet conveying apparatus for conveying a sheet-like material by bringing a conveying roll into contact with and rotating the sheet-like material, and by using a frictional force acting on the surface of the conveying roll and the surface of the sheet-like material. I have. However, if such a sheet conveying device is used for a long period of time, toner, paper dust and the like may adhere to the surface of the conveying roll, and the frictional resistance value of the sheet may decrease, resulting in defective conveyance. Therefore, regularly or when a transport failure occurs, a service engineer, a user, or the like removes paper dust or the like adhering to the transport roll surface and recovers its frictional resistance value.

Further, in order to reduce the labor and cost of such cleaning, the following techniques have been conventionally proposed. First, there is a technique in which a cleaning roll having a relatively high frictional resistance value is brought into contact with the surface of a transport roll (see, for example, JP-A-2000-44080). Secondly, there is a technique for transporting a cleaning sheet having an adhesive layer on the surface by a transport roll (for example, see Japanese Patent Application Laid-Open No. 2-19934). Third, there is also a technique for keeping the cleaning member in contact with the surface of the transport roll.

[0004]

However, each of these techniques has the following technical problems.
That is, in the first technique, in order to exhibit good cleaning performance, the frictional resistance value μ (C) of the cleaning roll surface must be equal to the frictional resistance value μ of the transport roll surface.
(R) is set much higher than (R) (μ (R) << μ
(C)) is required, but when the frictional resistance value μ (R) of the surface of the transport roll is high, effective cleaning becomes difficult. Further, if the cleaning roll is driven by the transport roll, there is a limit in the frictional force acting between the two, and it is difficult to remove foreign matters such as toner and paper powder firmly adsorbed on the transport roll surface.

[0005] The second technique has an advantage that it is possible to clean the transport roll once from the upstream side to the downstream side in the transport direction of the sheet-like material. The viscosity of the pressure-sensitive adhesive layer cannot be set too low so that no residue remains on the transport path, and effective cleaning becomes difficult. Similarly, it is difficult to remove foreign substances such as paper dust firmly adsorbed on the surface of the transport roll.

Although the third technique has a relatively high effect on removing foreign matters such as paper powder firmly adsorbed on the surface of the transport roll, the wear of the transport roll itself is accelerated. And the life is shortened.

The present invention has been made in view of these problems of the prior art, and has as its object to reduce the time required for a service engineer or the like to clean a transport roll, to improve cleaning performance and to prevent wear of the transport roll. It is another object of the present invention to provide a sheet conveying device capable of satisfying both.

[0008]

That is, the present invention relates to a sheet conveying apparatus provided with a conveying roll that conveys a sheet by rotating while coming into contact with the sheet. And (2) a cleaning member for cleaning the surface of the transport roll by contacting and separating.

As a more specific configuration of the cleaning member, it is preferable that the cleaning member is a pad-shaped member including a polishing layer on a surface in contact with the transport roll and an elastic layer inside the polishing layer. Further, it is preferable that an adhesive layer is provided on the back surface of the pad-shaped member that comes into contact with the transport roll.

Further, as a more specific mechanism for intermittently bringing the transport roll into and out of contact with the cleaning member, a contact / separation control unit for moving the transport roll toward and away from the sheet at a first timing; A rotation control unit that rotates and stops the transport roll at a second timing (independent of one timing), and the cleaning member is configured to contact the cleaning member when the transport roll is separated from the sheet side. And a cleaning mode in which the transport roll is rotated in a state in which the transport roller is in contact with the cleaning member (for a predetermined time).

In general, in a sheet transporting apparatus having such a configuration, a sheet transporting mode in which the transporting roll is rotated in contact with a sheet and a standby mode in which the transporting roll is stopped in a state of being separated from the sheet. And so on.

Further, the cleaning mode can be started by turning on the power to the apparatus, conveying a predetermined number of sheets, frequent occurrence of a conveyance failure, an instruction from a user, or a combination thereof.

The sheet conveying apparatus according to the present invention can be applied to any apparatus that conveys a sheet-like material, but effectively removes paper dust adhering to a conveying roll. From the effect of the present invention that
It is preferable that paper (paper) can be conveyed as a sheet. Specifically, the present invention is preferably applied to a printing apparatus, an image forming apparatus, an automatic document feeder (attached to a document reading apparatus of the image forming apparatus), and the like.

Further, some sheet conveying apparatuses have a plurality of conveying rolls from the upstream side to the downstream side in the conveying direction. Of the plurality of transport rolls, all or some of the transport rolls may be subjected to cleaning. Further, from the effect of the present invention that even a transport roll having a relatively high frictional resistance value can be effectively cleaned, of the plurality of transport rolls,
It is preferable to clean at least the transport roll having the highest frictional resistance value. In general, since the transport roller for separating a plurality of sheets one by one requires a high frictional resistance at the most upstream portion of the sheet-like material transport path, the transport rollers may be targeted for cleaning. preferable.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is an external perspective view of an image forming apparatus according to the present embodiment. This image forming apparatus includes an image forming apparatus main body 200 and an automatic document feeder 100 attached to the image forming apparatus main body 200. Further, the image forming apparatus main body 200 includes an operation panel 301 for indicating the status of these apparatuses 100 and 200 to the user, and for giving an instruction from the user, and an operation button group 302 for giving the instruction to the user.

The automatic document feeder 100 includes a document placing tray 101 on which a plurality of documents (sheets) can be placed, and a document discharging tray 199.
A document conveyance path from 01 to the document discharge tray 199 is formed.

FIG. 2 is a view for explaining the document transport path and its peripheral configuration. The dotted line in the figure is the document transport path. Explaining the peripheral configuration from the upstream side to the downstream side of the document transport path, a nudger roll 111, a first document transport roll pair 112 (comprising a feed roll 112a and a retard roll 112b), and a second document transport roll pair 113 , A document registration roll pair 114, an image reading unit 115, a third document transport roll pair 116, and a fourth document transport roll pair 117. A document transport guide (not shown) is formed along the document transport path, and a sensor 4 for detecting a document transport failure is provided in the document transport path.
0 is provided.

In this embodiment, these transport rolls 111 to 114, 116, 117 constituting a sheet transport apparatus are used.
Among them, the present invention is applied to a nudger roll (transport roll) 111 located on the most upstream side of the document transport path. The surface of the nager roll 111 is made of an elastic material such as silicon rubber.

FIG. 3 is a more detailed illustration of the dashed-dotted circle A in FIG. The nudger roll 111 is disposed between the document placing tray 101 and the upper cover 100U of the automatic document feeder 100. When the document is transported, one or more documents S are placed on the document placing tray 101. In addition, a cleaning pad (cleaning member) 5 described below is attached to the lower surface of the upper cover 100U. Further, by the contact / separation mechanism to be described later, the nager roll 111 holds the upper cover 1
It is configured so that it can approach and separate from both sides of the 00U side and the original placing tray 101 side.

Therefore, when the nager roll 111 approaches the upper cover 100U side (FIG. 3A)
), The surface of the nudger roll 111 comes into contact with the cleaning pad 5 and is separated from the document S on the document placing tray 101. On the other hand, when the nudger roll 111 approaches the original placing tray 101 side (see FIG. 3B), on the other hand, the surface of the nudger roll 111 comes into contact with the original S on the original placing tray 101. , Cleaning pad 5
Is separated from.

FIG. 4 illustrates the structure of the cleaning pad 5 shown in FIG. 3 in more detail. The cleaning pad 5 is composed of a plurality of layers (here, three layers), and includes an adhesive layer 51, an elastic layer 52, and a polishing layer 5, respectively.
Consists of three. The adhesive layer 51 has an upper cover 100
The polishing layer 53 is provided on the nadger roll 111 and the original placing tray 101 side. Note that the surface of the cleaning pad 5 is configured to be larger than the projection area of the nudger roll 111 in the contact direction.

The adhesive layer 51 securely fixes the cleaning pad 5 to the lower surface of the upper cover 100U. The elastic layer 52 is for applying a uniform pressure when the nager roll 111 contacts the cleaning pad 5, and is made of an elastic material such as a resin foam or rubber.

The polishing layer 53 is for removing foreign matters such as paper dust firmly adsorbed on the surface of the nager roll 111. The surface roughness depends on the Najar roll 1 used.
11 is determined in consideration of the balance between the material of No. 11, the cleaning property, and the life (abrasion property) of the nager roll 111. In the present invention, since the nager roll 111 does not always contact the cleaning pad 5 (polishing layer 53) but intermittently contacts the cleaning pad 5, the cleaning property is emphasized more and the wear is relatively increased. The polishing layer 53 having high polishing property (polishing property) can be employed.
Specifically, the polishing layer 53 can be made of sandpaper.

FIG. 5 is a block diagram for explaining a control system of the nager roll 111. As shown in FIG. This control system mainly includes a main control unit 60. The signals input to the main control unit 60 include a user's instruction signal input from the display panel 301 and the operation button group 302, and a conveyance failure signal of the document S input from the sensor 40. The signals output from the main control unit 60 include a rotation control command output to the rotation control unit 61, a contact / separation control command output to the contact / separation control unit 62, and a display command output to the display panel 301. Can be

The main controller 60 has a function (f1) for detecting whether the power to the image forming apparatus main body 200 is turned on or off.
A function (f2) for counting the number of transports of the document S after reset, a function (f3) for counting the number of transport failures of the document S after reset, and the frequency of transport failure based on the number of transports and the number of transport failures. (F4) to calculate
A function (f5) for counting the number of cleanings of the nudger roll 111 after the reset and a function (f6) for comparing any two numerical values are provided. The main control unit 60
A predetermined number of document transports N (F), a predetermined defective transport rate N (R), and a predetermined number of cleanings N (C) are stored in advance.

The rotation control unit 61 controls the rotation and rotation of the nager roll 111 based on a rotation control command from the main control unit 60.
It controls the stop (see the rotation arrow P in FIG. 5),
It is composed of a motor driver, a motor, a drive transmission mechanism and the like. The approach / separation control unit 62, based on the approach / separation control command from the main control unit 60, approaches and separates the nudger roll 111 to and from the document placing tray 101, that is, the cleaning pad 5
It controls the separation and approach to (see double arrow Q in FIG. 5, FIG. 3 (a) and FIG. 3 (b)), and is constituted by a solenoid, a spring (elastic member) and the like.

[0027]

[Table 1] With such a control system, the nudger roll 111 adopts three states of a transport mode, a standby mode, and a cleaning mode as shown in Table 1, respectively. That is,
In the transport mode, the nudger roll 111 is rotating and is in contact with the document S but is separated from the cleaning pad 5. In the standby mode, the nudger roll 111 is stopped, is separated from the document S, but is in contact with the cleaning pad 5. Further, in the cleaning mode, the nudger roll 111 rotates and is separated from the document S but is in contact with the cleaning pad 5.

In this embodiment, the cleaning mode is set at a predetermined timing. Hereinafter, the timing and conditions for shifting to the cleaning mode will be described as Examples 1 to 4, respectively. Further, the replacement timing of the nager roll 111 will be described as a fifth embodiment.

Embodiment 1 FIG. 6 is a flowchart for explaining the timing and conditions for shifting to the cleaning mode of this embodiment. Hereinafter, the present embodiment will be described with reference to this flowchart. In the present embodiment, first, the main control unit 60 determines whether the power is turned on to the image forming apparatus main body 200 (function f1, step S11). When the power is turned on, the cleaning mode is immediately shifted to the above-described cleaning mode (see FIG. 3A, step S12). After being sufficiently removed), the mode shifts to the standby mode.

Embodiment 2 FIG. 7 is a flowchart for explaining the timing and conditions for shifting to the cleaning mode of this embodiment. Hereinafter, the present embodiment will be described with reference to this flowchart. In the present embodiment, first, the display panel 30
It is determined whether or not a job (document reading) instruction has been issued by the user via the operation button group 1 or the operation button group 302 (step S21). When a job is instructed by the user, the main control unit 60 checks the number of conveyed originals S after the immediately preceding reset (function f2, step S22). Then, the confirmed number of conveyed sheets is compared with a predetermined number of document conveyed sheets N (F) stored in advance by the main controller 60 (function f).
6, step S23).

If the number of conveyed sheets is larger than the predetermined number N (F), the operation proceeds to the above-described cleaning mode (see FIG. 3A, step S24), and after a predetermined time elapses (the surface of the nager roll 111). After the foreign matter such as paper dust is sufficiently removed by the cleaning pad 5, the counter for the number of conveyed originals S is reset (step S25).
The job is executed (Step S26). On the other hand, if the confirmed number of conveyed sheets is not larger than the predetermined number N (F),
The job is executed immediately (step S26).
The process is executed until the job is completed (stick S27) (step S26), and the process ends.

Embodiment 3 FIG. 8 is a flowchart for explaining the timing and conditions for shifting to the cleaning mode of this embodiment. Hereinafter, the present embodiment will be described with reference to this flowchart. In the present embodiment, first, the display panel 30
It is determined whether or not a job (document reading) instruction has been issued by the user via the operation button group 1 or the operation buttons 302 (step S31). When the job is instructed by the user, the main control unit 60 checks the frequency of occurrence of the conveyance failure of the document after the reset (step S32). This is to calculate the frequency of defective transport (= number of defective transports / number of transported sheets) from the number of transported documents S after reset (function f2) and the number of transport failures of document S after reset (function f3). This can be confirmed (function f4).

Then, the confirmed transport failure frequency and a predetermined document transport failure rate N stored in advance by the main control unit 60 are set.
(R) (function f6, step S33). If the confirmed transport failure frequency is higher than the predetermined frequency N (R), the process shifts to the above-described cleaning mode (FIG. 3).
(See (a), step S34) After a lapse of a predetermined time (after foreign matter such as paper dust on the surface of the nudger roll 111 is sufficiently removed by the cleaning pad 5), the job is executed (step S35). On the other hand, if the confirmed conveyance failure frequency is not higher than the predetermined frequency N (R), the job is immediately executed as it is (step S35). And
The job is executed until the job ends (stick 36) (step S36), and the process ends.

Embodiment 4 FIG. 9 is a flowchart for explaining the timing and conditions for shifting to the cleaning mode of this embodiment. Hereinafter, the present embodiment will be described with reference to this flowchart. In the present embodiment, first, the main control unit 60 determines whether or not a cleaning instruction has been issued from the user (step S41). When a cleaning instruction is given, the process immediately shifts to the above-described cleaning mode (see FIG. 3A, step S12), and after a lapse of a predetermined time (for example, foreign matter such as paper dust on the surface of the nadger roll 111 is removed by the cleaning pad 5). After sufficient removal), the process ends.

Embodiment 5 FIG. 10 is a flowchart for explaining the replacement timing of the nadger roll 111 of the present embodiment. This flow can be performed, for example, immediately before the end processing shown in the flowcharts of the first to fourth embodiments. Hereinafter, the present embodiment will be described with reference to this flowchart. In the present embodiment, first, the number of times of the cleaning mode of the nudger roll 111 after the reset is checked (function f5, step S51). Then, the confirmed number of times of the cleaning mode is compared with a predetermined number of times of cleaning stored in advance (function f6, step S6).
52) If the number of times of the cleaning mode is greater than the number of times of use, a message is displayed on the display panel 301 to prompt the user to replace the nudger roll 111 (step S53).

Second Embodiment In the first embodiment, the present invention is applied to the sheet conveying device in the automatic current conveying device 100. However, the present invention is applied to other devices, for example, the sheet conveying device in the image forming apparatus main body 200. You can also.

The image forming apparatus main body 200 is provided with first to fourth sheet storage trays 201, 202, 203, 204 and sheet discharge tray 299 capable of storing different types of sheets (sheets) S, respectively. The paper transport path from each of the paper storage trays 201 to 204 to the paper discharge tray 299 is formed in the printer.

FIG. 11 is a view for explaining the paper transport path and its peripheral configuration. The dotted line in the figure is the paper transport path. The peripheral configuration from the upstream side to the downstream side of the paper transport path will be described.
0, 240, 250, 260, transport roll pairs 231, 241, 251, 261 in each tray, first paper transport roll pair 211, second paper transport roll pair 212, third paper transport roll pair 213, fourth paper transport Roll pair 214, fifth paper transport roll pair 215, sixth paper transport roll pair 216,
Seventh paper transport roll pair 217, Eighth paper transport roll pair 2
18, paper registration roll pair 219, photosensitive drum 22
0, a transfer device 221, a paper transport belt device 224, a fixing device 225, and a paper discharge roll pair 226. A paper transport guide (not shown) is formed along the paper transport path.

In the present embodiment, among the transport rolls 230... Constituting the sheet transport device, each of the pickup rolls (transport rolls) 230, 240, 250, and 260 located at the most upstream side of the paper transport path. The present invention is applied. That is, each paper storage tray 20
A cleaning pad is provided on the lower surface of each of the sheet storage trays 201 to 204 and the sheet storage trays 201 to 204, and the contact and separation and rotation of each of the pickup rolls 230, 240, 250, and 260 can be controlled. Note that a specific example is the same as in the first embodiment, and a description thereof will be omitted.

[0040]

As described above in detail, according to the present invention, it is possible to achieve both the cleaning performance and the prevention of abrasion of the transport roll while reducing the trouble of cleaning the transport roll by a service engineer or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view of an image forming apparatus according to an embodiment.

FIG. 2 is a view for explaining a document transport path of the automatic document transport device of the image forming apparatus shown in FIG. 1;

FIG. 3 is an enlarged sectional view of a part of FIG. 2;

FIG. 4 is a diagram for explaining the configuration of the cleaning pad in more detail;

FIG. 5 is a block diagram illustrating a control system of a nager roll.

FIG. 6 is a flowchart illustrating a cleaning mode transition timing and conditions according to the first embodiment.

FIG. 7 is a flowchart illustrating a cleaning mode transition timing and conditions according to the second embodiment.

FIG. 8 is a flowchart illustrating a cleaning mode transition timing and conditions according to the third embodiment.

FIG. 9 is a flowchart illustrating a cleaning mode transition timing and conditions according to the fourth embodiment.

FIG. 10 is a flowchart illustrating a timing of replacing a nager roll according to the fifth embodiment.

FIG. 11 illustrates a sheet transport path of a main body of the image forming apparatus illustrated in FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 100 ... Automatic document feeder, 200 ... Image forming apparatus main body, 101 ... Document placement tray, 199 ... Document discharge tray, 201-204 ... Paper storage tray, 299 ... Paper discharge tray, 111 ... Nager roll (conveyance roll) , 2
Reference numerals 30, 240, 250, 260: pickup roll (conveyance roll), 301: display panel, 302: operation button group, 40: sensor, 5: cleaning pad, 51
... adhesive layer, 52 ... elastic layer, 53 ... polishing layer, 60 ... main control unit, 61 ... rotation control unit, 62 ... contact / separation control unit, S: original

Claims (4)

[Claims] 1. A sheet conveying apparatus having a conveying roll that conveys a sheet by abutting and rotating on the sheet, wherein the conveying roller is intermittently contacted with and separated from the conveying roll at a predetermined timing to clean the surface of the conveying roll. A sheet conveying device having a cleaning member. 2. The sheet conveying device according to claim 1, wherein the cleaning member is a pad-shaped member including a polishing layer on a surface that comes into contact with the conveyance roll, and an elastic layer inside the polishing layer. 3. The transport roll, comprising: a contact / separation control unit that moves the transport roll toward and away from the sheet at a first timing; and a rotation control unit that rotates and stops the transport roll at a second timing. 3. The sheet according to claim 1, further comprising a cleaning mode in which the cleaning member is provided so as to come into contact with the cleaning member when the sheet is separated from the sheet side, and the transport roll is rotated in a state of being in contact with the cleaning member. 4. Transport device. 4. The sheet conveying apparatus according to claim 3, wherein the cleaning mode is started by at least one of power-on to the apparatus, conveyance of a predetermined number of sheets, frequent conveyance failure, and an instruction from a user, or a combination thereof. .