JPS60258051A - Paper conveying roller - Google Patents

Abstract

PURPOSE:To prevent the occurrence of inking transference as well as to convey sheets of paper different in size and thickness in a way of reducing their slippage, by using such a tape material, having flexibility but having no ink adsorbability, on a roller circumferential part, and also using an elastic material of rubber or the like in space between the roller circumferential part and a roller core bar part. CONSTITUTION:Cut paper is conveyed as being held between a driving roller and a follower roller situated in the opposite side. A thin tape material of Teflon or the like, having no ink adsorbability, is used on a circumferential part 4a of the follower roller. And, an elastic rubber material suitable for paper conveyance is used in space between the roller circumferential part 4a and a core bar part 4c. Therefore, the cut paper is accurately conveyed irrespective of size and thickness, while such a possibility that ink is transferred, causing deterioration in printing quality (paper face smudging) is prevented from occurring.

Description

[Detailed Description of the Invention] [Subject of the Invention] The present invention relates to a paper transport p-ra in a printing device, and in particular to a paper transport p-ra suitable for transporting cut sheets of different sizes and thicknesses, various forms of different types, etc. Regarding conveyance rollers.

[Background of the invention]

Conventionally, the following types of paper conveyance rollers in printing devices are known, for example.

The first one, the most common one, is the p-ra, which is made of cacom material at the outer periphery. This roller has the drawback that the ink is transferred to the surface of the paper immediately after printing, and the ink adhering to the roller surface is further transferred to another part of the paper surface, staining the paper surface.

The second roller is a roller whose outer periphery is made of a grindstone or metal.This p-roller can prevent the transfer of ink immediately after printing as described above. However, since this roller lacks elasticity, when handling various types of paper, the paper may skim or the like, resulting in problems with the accuracy of the conveyance amount.

As the third roller, there is one described in Japanese Patent Application No. 1989-89650 (published) proposed by the present applicant. However, it has been found that when multi-part paper is conveyed by this p-ra, misalignment of each sheet occurs. We solve this problem and provide a paper transport roller that can stably transport paper of different sizes and thicknesses by preventing ink transfer, and can transport multi-part paper while preventing paper feed misalignment. [Summary of the Invention] In the present invention, the outer peripheral portion of the roller is made of a material that does not have the ink adsorption properties of a flexible tape material.

An elastic material such as rubber is used between the outer circumference of the roller and the metal core.

[Embodiments of the invention]

FIG. 1 is a perspective view showing an embodiment in which the present invention is applied to a printing device, and FIG. 2 shows the paper conveyance roller (
1 is a perspective view of a roller (hereinafter simply referred to as a "roller").

There are two pairs of rollers that transport the cut paper 1, and rollers 3, which are provided on the front and rear sides of the print head 2 as a boundary, are driving rollers that contact the back side of the zero-force cut paper 1. A follower roller 41 is placed opposite to the follower roller 3.
~46 locations will be established. The cut paper 1 is connected to the driving roller 3
and 7 lower rollers 41 to 46, and is conveyed between the print head 2 and the platen 80 by rotating the drive roller 3 by the drive of the motor 5. The follower rollers 41 to 46 are attached to the roller shaft 6 and can each rotate freely. The force with which the follower rollers 4 clamp the cut paper 1 is obtained by pressing the roller shaft 6 against the driving roller 3 using the spring 7.

Outer periphery 4a of follower rollers 41 to 46 shown in FIG.
is made of a thin tape material such as Teflon. It is important that this tape material does not have ink adsorption properties. The core metal part 4c of this roller is made of a smooth metal so that it can slide on the roller shaft 6. Also, the M4b between the outer peripheral part 4a and the core metal part 4c of this roller is stable paper 1''J t, f, = 4 fi O, 1% 6''
``&'fl Q ``C'b' lo 1) By configuring the 7 follower p-ra 41 to 46 as described above,
This has the effect of accurately transporting the cut paper 1 regardless of its size, thickness, etc., and preventing deterioration of printing quality (paper surface staining) due to ink transfer. Another method is to coat the outer circumferential portion 4a of the seventh roller roller with a material that does not have ink adsorption properties. In addition to elastic rubber materials, foamed plastic materials and the like can also be used.

Next, the functions and effects of the 7-lower roller according to the present invention will be explained in detail with reference to FIGS. 3, 4, and 5.

FIG. 3 is a diagram comparing the transfer density (paper surface stain) with a known roller. In this figure, the density (pcs) is the reflectance of the unprinted area, and when the reflectance of the dirty area is Ri, it is PC
B = (lt'Lp - Ri)/'Rp. Also,
In the figure, the white lines indicate the density at the time of 1st feed after being repeated twice, and the shaded lines indicate the density at the 10th time. As a result, the roller according to the present invention has almost no ink adsorption property on the roller surface 4a, and the roller surface of the roller of Japanese Patent Application No. 57-89650 has a large amount of dirt on the paper surface 4. compared to the roller of the rubber member and the roller of the grindstone. It can be seen that the effect can be obtained.

Next, FIG. 4 shows data comparing the amount of deviation t (FIG. 5) between the uppermost sheet and the lowermost sheet of multi-part paper due to the follower roller when A4 size paper is vertically fed.

In the follower roller of the present invention, the roller surface member 4a is a member with excellent flexibility, and the intermediate member 4b is also highly elastic, so compared to other rollers, it has a large effect on the conveyance performance of multi-part paper. can get.

Further, FIG. 6 shows a comparison of the paper surface stains and paper feeding performance of each of the four lathes. Here, ○ indicates excellent, Δ indicates good, and × indicates poor. From FIG. 6, it can be seen how effective effects are brought about in the printing device that handles the Follower Q-5 cut paper 1 of the present invention.

Note that the tape member of the follower roller according to the present invention may be a flexible member that does not have ink adsorption properties.
For example, in addition to a tape made of Teflon, a tape member made of vinyl may be used. [Effects of the Invention] According to the present invention, in a paper conveyance roller in a printing device, etc., the outer peripheral portion of the roller can be The tape material is flexible and does not have ink adsorption properties, and an elastic material such as rubber is used between the roller outer periphery and the roller core to prevent ink transfer and reduce size and thickness. It is possible to stably transport sheets of paper with different values with a reduced amount of deviation.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment in which the present invention is applied to a printing device, FIG. 2 is a perspective view of a roller according to the embodiment, FIG. 3 is a diagram comparing transfer density with a known roller, and FIG. FIG. 5 is a diagram showing a state of misalignment, and FIG. 6 is a diagram showing a comparison result with a known roller. 1: cut paper, 3: drive roller, 41-46: 7 roller roller, 6: roller shaft, 7
: Spring, 8 Nibraten. Representative Patent Attorney Akio Takahashi Item 1, Figure 2, b

Claims (2)

[Claims] (1) IWI outside the paper transport roller °C10-ra
1. A paper conveyance roller, characterized in that the m-member is a member that does not have ink adsorption properties and has flexibility, and the space between it and the core of the roller is made of an elastic member. (2) The paper transport roller described in item 1, wherein the outer peripheral member of the roller is made of a thin Teflon or vinyl material.