JP2918682B2 - Paper feed roller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper feed roller, and more particularly, to a measure for smoothing a paper feed operation or the like.

(Prior Art) Conventionally, for example, rollers used for paper feeding or paper separating mechanisms used in office equipment such as a copying machine and a print printer as disclosed in Japanese Patent Application Laid-Open No. 56-127501 are disclosed. The following performance is required.

… The paper must be sent accurately, or the paper must be accurately separated (separated) one by one… The hardness change due to temperature is small, and the paper feed and paper separation performance is small… Excellent in abrasion resistance … Variation, especially variation in weight and hardness is small.… The outer peripheral surface of the roller is always kept clear. (Normally, paper contains inorganic fillers and resins, If the usage time is long, these adhere to the outer peripheral surface of the roller, and the above-described characteristics, which are the substrate characteristics, are often impaired.) Conventionally, as a material for this type of roller, CR,
Synthetic rubber such as EPT and urethane rubber or natural rubber and their foams are used.

(Problems to be Solved by the Invention) Among them, CR, EPT, natural rubber, and foams thereof are inexpensive, but properties such as hardness change depending on temperature, and paper feeding and paper sorting functions are reduced. Easy to fall.
Urethane rubber and its foam also have a problem in terms of temperature characteristics, and generally have a drawback that a large load is applied, which tends to cause distortion, and problems are liable to occur in paper feeding and paper separation.

The present invention has been made in view of these points, is free from distortion due to load, is stable against temperature, humidity and oil, and is stable against adhesion of a substance coated on the paper surface. It is an object of the present invention to obtain a paper feed roller having excellent wear resistance.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, short fibers are arranged in the roller main body of the paper feed roller. Specifically, it is assumed that a paper feed roller contacts the paper surface and feeds the paper. The paper feed roller is made up of a roller body made of rubber and short fibers protruding from the entire outer peripheral surface of the roller body.
The length is 6 mm or less, the ratio of fiber length to fiber diameter is 30 or more, the initial elastic modulus is set to 30 g / d or more, and the volume ratio of short fibers to rubber is 3 to 30% by volume, The short fibers were oriented at least 50% in the radial direction of the roller body, and project from the outer peripheral surface of the roller body by 0.01 to 1.0 mm.

(Operation) According to the present invention, in the present invention, short fibers are provided inside the paper feed roller and on the contact surface with the paper, so that the paper feed roller has little change in properties such as hardness due to temperature. , Paper feeding and paper sorting functions are always ensured.
Further, even when a large load is applied, distortion is unlikely to occur, so that paper feeding and paper sorting can be performed smoothly. Further, it is stable to temperature, humidity and oil, stable to adhesion of a substance coated on the paper surface, and excellent in abrasion resistance.

(Example) Next, an example of the present invention will be described with reference to the drawings. In this example, a paper feed roller provided in a copying machine will be described as an example.

As shown in FIG. 3, the paper feed roller 1 is used as rollers 5, 6 provided in a paper feed unit 2 provided at a paper feed port of a copying machine. That is, FIG. 3 schematically shows a paper feeding section 2 provided with a paper feeding roller 1 (FIGS. 1 and 2) according to an embodiment of the present invention. The rotating shafts 3 and 4 are rotatably mounted on the main body. The rotating shafts 3 and 4 are respectively driven to rotate by a driving device (not shown) of the copying machine main body. A plurality of first rollers 5, 5,... Are attached to one of the rotating shafts 3 at predetermined intervals, and the other rotating shaft 4 corresponds to the first rollers 5, respectively. A plurality of second rollers 6, 6,... Which rotate in the opposite direction while being in contact with the first roller 5, are mounted. During the paper feeding operation, these rollers 5,
6 rotate in opposite directions as indicated by the arrows in FIG. 3,
The paper 7 fed by the paper feeding mechanism in the copying machine is sandwiched between the rollers 5 and 6, and is configured to be fed forward in FIG.

The paper feed roller 1 of the present invention constitutes at least one of the first and second rollers 5, 6, and in the present embodiment, all of the first roller 5 is a paper feed roller of the present invention described later. The feed roller 1 is used, and the second roller 6 is entirely made of metal. If necessary, all of the second roller 6 may be constituted by the roller 1 of the present invention, and the first roller 5 may be made of another metallic material.
All of the rollers 5 and 6 can be constituted by the roller 1 of the present invention. Further, a part of the first roller 5 and the second roller 6 is constituted by the roller 1 of the present invention, and the other rollers are made of another material. The adoption state of the roller 1 of the present invention can be variously changed.

Hereinafter, the raw rubber constituting the roller main body 1a of the paper feed roller 1 of the present embodiment will be described. This raw rubber is made of natural rubber, styrene butadiene rubber, chloroprene rubber, isoprene rubber, ethylene propylene rubber, butyl rubber, acrylonitrile butadiene rubber, silicon rubber, urethane rubber, fluorine rubber, halogenated butyl rubber, hydrogenated It is appropriately selected from crosslinked rubbers such as NBR and chlorosulfonated polyethylene, and thermoplastic elastomers such as polyolefin, polyester, polyether, polyamide and polyurethane.
Further, a reinforcing agent such as carbon black and an inorganic filler such as silica, calcium carbonate, talc, and clay can be arbitrarily selected.

Further, in the above rubber composition, rubber extender oil, rubber chemicals and rubber additives are blended if necessary,
As extender oils for rubber, aromatic, naphthenic,
Paraffinic ones are preferred. Further, as rubber chemicals and rubber additives, crosslinking agents such as sulfur and peroxide, vulcanization accelerators such as zinc white and stearic acid, vulcanization such as sulfenamide-based, thiuram-based, thiazole-based, and guanidine-based vulcanizing agents. Accelerators, amine-based, phenol-based, sulfur-based, phosphorus-based antioxidants or antioxidants, ultraviolet absorbers,
An ozone deterioration inhibitor, a tackifier, a plasticizer, and the like are used.

As the raw material rubber, it is desirable to use natural rubber or isoprene rubber in an amount of 60% by weight or more from the viewpoint of cost reduction, but it is not necessarily limited to this.

As a characteristic feature of the present embodiment, short fibers 8 are provided so as to protrude over the entire outer peripheral surface of the roller main body 1a of the paper feed roller 1 according to the present invention. As the short fibers 8, those having a fiber length L of 6 mm or less, a ratio L / D of the fiber length L to the fiber diameter D of 30 or more, and an initial elastic modulus of 30 g / d or more are used. I have. Examples of short fibers having an initial elastic modulus of 30 g / d or more include, for example, Kevlar manufactured by DuPont, para-aramid fibers such as Teijin's Technora, Nomex manufactured by DuPont, meta-aramid fibers such as Conex manufactured by Teijin, Aromatic fibers such as Kuraray's Vectra, vinylon, polyester, polypropylene, nylon 6, nylon 6,
6.Synthetic, natural and semi-synthetic fibers such as cellulose fibers such as cotton and Mosanto santoweb, as well as inorganic fibers such as glass, carbon, ceramic, Ube Industries' Tyranno fibers and boron, steel, stainless steel, copper, etc. Is appropriately selected from the above metal fibers.

From the viewpoint of increasing the elastic modulus, it is desirable to use short fibers having a high initial elastic modulus, and the ratio of the fiber length L to the fiber diameter D is preferably used.
Larger L / D is better. It is desirable that the fiber length L is also long, but if it exceeds 6 mm, the workability is significantly impaired.
mm. Further, the fiber length L and the fiber diameter D
Short fibers with a ratio L / D of less than 30 or short fibers with an initial elastic modulus of less than 30 g / d have little effect for the purpose of increasing the hardness (higher elastic modulus) and lowering the dynamic magnification, The value is set to the above value because it has been confirmed that there is a concern that distortion due to a load is generated and that the load is easily affected by environmental changes.

The mixing amount of the short fibers 8 is set to 3 to 30% by volume from the viewpoint of improving the elastic modulus and ensuring workability.

And specifically, in this example, the fiber diameter is 14μ, the fiber length
Adopt 3mm Conex (manufactured by Teijin) and use this short fiber 8
Is set so that 50% or more is oriented in the radial direction of the roller body 1a, that is, the direction (Z direction) perpendicular to the roller outer peripheral surface.
It is set to 22%. Also, a part of this short fiber 8 is 0.5 m
It protrudes from the roller surface by about m. When the mixing amount of the short fibers 8 is less than 3% or the orientation ratio in the roller radial direction is set to less than 50%, the outer peripheral surface of the roller main body 1a is susceptible to distortion due to load and environmental change. There is a concern. There is a similar concern when the amount of protrusion of the short fibers 8 is set to less than 0.01 mm. Furthermore, the mixing amount of the short fibers 8 exceeds 30%, or the protrusion amount of the short fibers 8 is 1.0 m.
If it is set to exceed m, the above value is set because workability becomes extremely difficult and impractical.

Next, a manufacturing process of the paper feed roller 1 in which the short fibers 8 are mixed will be described.

First, the raw materials are kneaded at a mixing ratio (weight ratio) as shown in Table 1, and the short fibers 8 described above are mixed into the kneaded material.

Table 1 Chloroprene rubber 100 Carbon black (N550) 30 Zinc oxide 5 Magnesium oxide 4 Stearic acid 1 Short fiber (Cornex) 40 The kneaded material in which the short fiber 8 is mixed is then extruded by an extruder. The short fibers 8 are oriented in the roller radial direction to form a cylindrical roller rubber base material (not shown). Then, the rotation shaft 3,
Insert 4 and vulcanize in this state. By buffing the outer peripheral surface of the roller 1 thus formed, a part of the short fiber 8 is projected from the roller surface by a predetermined dimension as shown in FIG. As a result, the paper feed roller 1 that includes the short fibers 8 extending in the radial direction and that partially protrudes is formed.

In the paper feed mechanism having the above-described configuration, the paper 7 to be transported is sandwiched between the first roller 5 and the second roller 6 and transported by the rotation of these rollers 5, 6. By forming at least one of 6 (preferably all on one side or all on both sides) by the paper feed roller 1 of the present invention, excellent performance not seen in the conventional paper feed or sheet separating mechanism is exhibited. That is, there is no distortion due to the load, there is little change in hardness due to temperature, and the roller surface is uniform.
Stable and accurate feeding of paper over a wide temperature range without the instability of paper feeding, paper skew, distortion of the contact area with paper, etc., and accurate separation (separation) of paper one by one. In addition, the change in driving resistance during paper feeding or paper separation is small, and stable paper feeding or paper separation is performed. Furthermore, the resin, inorganic filler, etc., coated in the paper, are taken into the short fibers protruding from the roller surface (outer peripheral surface), and the surface is cleared without adhering to the roller surface. The stability and accuracy of paper feeding and paper handling are maintained even after long-term use.

In the above embodiment, the roller 1 is used for the paper feeding section 2 of the copying machine. However, the present invention is not limited to this, and other office machines such as various printing printers, facsimile machines, printing machines, typewriters, etc. It can be used for a paper feeding or paper sorting mechanism. In this embodiment, the shape of the paper feed roller 1 is a ring having a short length. However, the paper feed roller 1 may be formed in a long cylindrical shape. In addition, the length of the short fiber, the ratio of the fiber length to the fiber diameter, the initial elastic modulus, the capacity ratio to rubber, the orientation ratio of the roller in the radial direction, the amount of protrusion from the roller surface, and the like are not limited to those of the present example. It can be set appropriately within the range described above.

(Effects of the Invention) As described above, according to the present invention, since the short fibers are provided in the roller body, the paper feed roller has a small change in properties such as hardness due to temperature, and has a small paper feed,
The paper sorting function is always ensured, and the reliability can be improved. In addition, since distortion is unlikely to occur even when a large load is applied, it is possible to prevent paper slip phenomenon, instability of paper feed, paper deviation, distortion of a contact portion with paper, etc. It is possible to facilitate the paper sorting operation. Further, it is possible to obtain a paper feed roller which is stable to temperature, humidity and oil, stable to the adhesion of a substance coated on the paper surface, and excellent in abrasion resistance.

[Brief description of the drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a side view in which a part of a paper feed roller is cut away, FIG. 2 is a perspective view thereof, and FIG. It is a front view which shows a part. 1 Paper feed roller 1a Roller body 7 Paper 8 Short fiber

Claims (1)

(57) [Claims] 1. A paper feed roller for feeding paper in contact with the paper surface, comprising a roller body formed of rubber, and short fibers protruding from the entire outer peripheral surface of the roller body. The short fibers have a length of 6 mm or less, a ratio of fiber length to fiber diameter of 30 or more, an initial elastic modulus of 30 g / d or more, and a short fiber to rubber volume ratio of 3 to 30 volumes. A paper feed roller characterized in that 50% or more of the short fibers are oriented in the radial direction of the roller body and project from the outer peripheral surface of the roller body by 0.01 to 1.0 mm.