JP3640639B2 - Sheet material supply device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet material supply apparatus provided with a sheet material neutralizing mechanism in a copying machine, a printer, a facsimile, or the like.
[0002]
[Prior art]
In copying machines, printers, facsimiles, and the like, weight reduction has been achieved by replacing members conventionally made of metal with resin members, and this tendency is particularly prominent in small machines. Under such circumstances, even in a sheet material supply device (hereinafter referred to as a sheet feeding device) constituting a copying machine or the like, the supplied sheet material (supply sheet material) is guided toward the image forming unit or the image reading unit. The sheet feeding guide portion to be replaced is replaced with a resin product from a metal. In this paper feeding device, a cylindrical paper feeding roller having a layer made of rubber or the like having a high frictional resistance is formed on a recording paper set in a paper feeding cassette, a manual paper feeding tray, a document tray, or the like. By rotating while contacting a sheet material such as a document, the sheet material is supplied toward the paper feed guide section. Here, when the paper feed guide portion is made of metal, static electricity is hardly generated even if the sheet material contacts the paper feed guide portion, and even if it occurs, the paper feed guide portion is supported. Since the charge easily escapes to the member or the like, there is no problem that static electricity accumulates on the sheet feeding guide portion or the sheet material in contact therewith.
[0003]
[Problems to be solved by the invention]
However, as the weight of the apparatus advances, the paper feed guide portion is often made of resin. In this case, when the sheet material supplied by the paper feed roller contacts the paper feed guide portion, Static electricity is easily generated due to frictional charging. The generated static electricity is transmitted to and accumulated in the remaining sheet material set in the sheet feeding cassette or the like via the sheet material being supplied. Furthermore, the static electricity accumulated in the sheet material makes it difficult for a plurality of sheet materials to be peeled off one by one, and so-called double feeding in which two or more sheet materials are supplied while overlapping is likely to occur. This problem is particularly likely to occur when a sheet material is separated from a plurality of sheet materials by a nail separation method. This is because the nail separation method is simple in structure, but it is inferior to the sheet material separation performance using the friction pad to separate the sheet material, and is easily affected by static electricity. Furthermore, such accumulation of static electricity causes noise and malfunctions of electronic components. Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resin-made paper feed guide. An object of the present invention is to provide a sheet material supply device that prevents sheet materials from being double-fed or electronic components from malfunctioning due to static electricity generated when the sheet material comes into contact with a portion.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a sheet material supply device that feeds a supply sheet material to a resin-made paper feed guide portion by a rotating paper feed roller, and is attached to a rotating shaft of the paper feed roller. and more planes are formed conductive parts material, the part and the conductive parts material which is formed in plane to plane contact, the paper feed guide conductive fitted with a conductivity unit sheet A sheet material supply device comprising: a sheet material; and a grounding means for grounding a rotation shaft of the sheet feeding roller.
As a result, when the sheet feeding roller is in contact with the sheet feeding guide portion by effectively utilizing the sheet feeding roller, which is an existing member, only by adding a conductive sheet material that is very lightweight and has a small installation capacity. Static electricity (electric charge) generated can be removed.
Moreover, since the electrically conductive sheet material and the paper feed section of the conductive attached to the rotary shaft of the roller member is in surface contact, than if the conductive sheet material is in contact with the cylindrical said rotary shaft, Charges can be released more reliably.
[0005]
Also, one of the feed sheet material sent from the plurality of the supply sheet material, if it is intended to be separated by a pawl separation system, generally as compared to the method of separating using friction pads Since the separation performance is inferior, the multi-feed preventing effect of the supply sheet material according to the present invention is more noticeable.
Further, if the grounding means grounds the rotation shaft of the paper feed roller via a support member that supports the rotation shaft of the paper feed roller, the existing member can be used more effectively. -Does not impair weight reduction.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
FIG. 1 is a cross-sectional view of a printer having the paper feeding device X according to the embodiment of the present invention as a component, and FIG. 2 is a cross-sectional view showing a schematic configuration of the paper feeding device X according to the embodiment of the present invention. FIG.
First, a schematic configuration of a general printer as an example to which the paper feeding device X according to the embodiment of the present invention is applied will be described with reference to FIG.
The paper feeding device X is used to supply recording paper s (an example of a sheet material) from a paper feeding cassette 10 of the printer. The recording paper s set in the paper feed cassette 10 is urged to the paper feed roller 1 by the lift plate 11 and is sent out toward the paper feed guide unit 2 by the rotation of the paper feed roller 1, and the paper feed After being guided to the conveyance roller 20 by the guide unit 2, it is conveyed to the image forming unit 30 by the conveyance roller 20. Further, an image such as a toner image is formed on the recording paper s by the image forming unit 30, and the image is heated and fixed on the recording paper s by the fixing unit 40, and then the recording paper s is discharged to the paper discharge tray 50. A conductive sheet material 3 for removing static electricity generated when the sheet material comes into contact with the paper feed guide 2 is attached to the paper feed guide portion 2, which will be described later.
[0007]
Next, the charge eliminating mechanism of the paper feeding device X will be described with reference to FIG.
As described above, for example, the conductive sheet 3 made of conductive polymer polyethylene or the like is attached to the paper feed guide portion 2 so as to be in direct contact (with conductivity), and the conductive sheet is curved. A part of the lever is configured to come into contact with a metal member 1b, which will be described later, attached to the metal rotating shaft 1a of the paper feed roller 1. Further, the rotary shaft 1a of the paper feed roller 1 is grounded via a metal bearing 1c (corresponding to the support member) that supports the rotary shaft 1a. That is, the metal side wall 60 that supports the bearing 1c is configured to come into contact with the grounded electrical component mounting plate 70, whereby the paper feed guide portion 2 serves as the conductive sheet 3, which will be described later. The metal member 1b, the rotating shaft 1a of the paper feed roller 1, the bearing 1c, the side wall 60, and the electrical component mounting plate 70 are grounded. Here, the portion of the rotary shaft 1a of the paper feed roller 1 that is in contact with the conductive sheet 3 is configured such that a U-shaped metal member 1b is attached to form three planes. As a result, when the sheet feeding roller 1 rotates, the conductive sheet 3 and the metal member 1b of the rotating shaft 1a are brought into plane contact (the contact area is widened), so that the columnar rotation The electric charge charged in the paper feed guide portion 2 can be surely released (grounded) as compared with the case where it contacts the peripheral surface of the shaft 1a. Of course, a plane is formed by making the cross-sectional shape of the rotary shaft 1a in contact with the conductive sheet 3 or the entire rotary shaft 1a a square shape (square axis), etc., and making contact with the conductive sheet 3 in plane contact. It doesn't matter if you do.
By providing the conductive sheet material 3 in the configuration as shown in FIG. 2, static electricity generated by the contact between the paper feed guide 2 and the recording paper s is surely eliminated, and the static electricity is removed from the paper feed cassette. Therefore, it is possible to prevent the remaining recording paper s set to 10 from being accumulated. As a result, it is possible to prevent a plurality of recording papers s from being peeled off due to static electricity, so that two or more recording papers are fed at once, and electronic components from malfunctioning due to electrostatic noise. In particular, the method of separating the recording paper s by the separation claw 12 provided in the paper feed cassette 10 or the like as shown in FIG. 2 (claw separation method) is more general than the method of separating using a friction pad. Since the separation performance is inferior, the effect of preventing double feeding of the recording paper s according to the present invention appears more remarkably.
[0008]
【The invention's effect】
As described above, according to the present invention, the static electricity generated when the sheet material comes into contact with the resin-made paper feeding guide portion can be surely eliminated, and the static electricity is transmitted to the remaining sheet material, so that the sheet material is double-fed. Can be prevented. In particular, the effect is remarkable in a paper feeding device that employs a nail separation method that is likely to cause double feeding due to static electricity. In addition, malfunction of electronic components due to electrostatic noise can be prevented. In addition, by adding a conductive sheet material that is very lightweight and has a small installation capacity, the paper feed guide is grounded via the existing feed roller rotation shaft and its bearings. There is no need to provide a simple ground wire, and there is no loss of size and weight. In particular, in small machines (printers, copiers, etc.) where most of the members are made of resin in order to reduce the size and weight, the strength of the rotating shaft of the paper feed roller and the support member of the rotating shaft is required. Since metal is used only for some of the members, it is particularly effective to use these existing metal members for grounding.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a printer having a sheet feeding device X according to an embodiment of the present invention as a constituent element.
FIG. 2 is a cross-sectional and plan view illustrating a schematic configuration of a paper feeding device X according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Paper feed roller 1a ... Rotary shaft 1b ... U-shaped metal member 1c ... Bearing 2 ... Paper feed guide part 3 ... Conductive sheet 10 ... Paper feed cassette 11 ... Lift plate 12 ... Separation claw 20 ... Conveying roller 30 Image forming unit 40 Fixing unit 50 Paper discharge tray 60 Side wall 70 Electrical component mounting plate s Recording paper

Claims (3)

In a sheet material supply device that feeds a supply sheet material to a resin-made paper feed guide section by a rotating paper feed roller,
And the paper feed roller mounted on a rotary shaft of one or more planes are formed conductive parts material,
Said portion and the conductive parts material which is formed in plane to plane contact, attached with a conductive to the paper feeding guide portion conductive sheet material,
A sheet material supply device comprising: a grounding means for grounding a rotation shaft of the paper feed roller.   The sheet material supply apparatus according to claim 1, wherein one sheet of the supply sheet fed from the plurality of sheets of the supply sheet is separated by a nail separation method. Said grounding means, the supply of sheet material according to claim 1 or 2 Neu not Re or is for grounding the rotary shaft of the feed roller via a supporting member for supporting the rotation shaft of the feed roller apparatus.

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