JPH04298440A - Sheet paper travelling mechanism - Google Patents

Abstract

PURPOSE:To prevent diagonal travelling of a sheet paper almost without changing a convetional structure. CONSTITUTION:For a first and a second rollers 2, 10 for feeding a sheet paper 8, its rotation shaft is perpendicularly disposed to a feed direction of the sheet paper 8. The first roller 2 has one-way clutch 3 for giving rotation to the roller 2 only in a feed direction of the sheet paper 8. At a timing when the forward end of the sheet paper 8 is wound around the second roller 10 for a predetermined quantity, a motor is controlled to rotate inversely. At this time, the first roller 2 is not rotated, and a forward end part of the sheet paper 8 is flexed, so the forward end of the sheet paper 8 is aligned along a contact line 15. In this condition, the motor is controlled to rotate normally again, and the sheet paper 8 is fed by the second roller 10.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet paper transport mechanism for facsimiles, copying machines, etc., and more particularly to a mechanism for preventing sheet paper from being skewed.

0002

[Prior Art] Conventionally, a sheet paper traveling mechanism that prevents skewing of sheet paper has been achieved by adjusting the pressure balance between rollers and members pressed by the rollers, or by improving the positional accuracy of rollers and members. Or, furthermore, a mechanism such as providing a paper width guide for the sheet paper is used. In addition, the sheet paper transport system for electrophotographic recording consists of a pair of rollers that are pressed against each other, one of which is a rubber roller and the other is a metal roller, which reduces surface friction. The roller is rotated after hitting the surface to prevent skewing.

0003

[Problems to be Solved by the Invention] However, in the conventional skew prevention mechanism described above, when adjusting the pressure balance between the roller and the member pressed by the roller, it is difficult to completely prevent the skew of the sheet paper due to variations in adjustment. I can't do it. Furthermore, in the case of improving the positional accuracy of the rollers and members, the structural components become expensive. Furthermore, when providing a paper width guide for sheet paper, there are drawbacks such as the inability to prevent skewing of sheet paper that is not stiff. If metal rollers cannot be used due to constraints, it is impossible to take measures against skew. The present invention has been made in view of the above-mentioned conventional disadvantages, and its purpose is to provide a sheet paper transport mechanism that prevents skew feeding without substantially changing the conventional structure.

0004

[Means for Solving the Problems] In order to achieve this object, the sheet paper transport mechanism according to the present invention has a sheet paper transport mechanism in which the sheet paper feeding direction and its rotation axis are arranged at right angles, and are spaced apart from each other. It consists of first and second rollers, a pressing member that is pressed by these rollers and works with both rollers to feed a sheet of paper, and a motor that is controlled to rotate in forward and reverse directions and drives both of the rollers. Among the rollers, the first roller on the front side with respect to the feeding direction of the sheet paper is equipped with a one-way clutch that rotates only in the feeding direction of the sheet paper, so that the leading edge of the sheet paper wraps around the drive roller by a predetermined amount. At this point, the second roller is once reversed, and when the leading edge of the sheet paper is released from the second roller, both rollers are rotated forward again.

[0005]

[Operation] In the sheet paper transport mechanism according to the present invention, the sheet paper is bent once unwound from the second roller located earlier in the sheet paper feeding direction, and the bending force at that time bends the sheet paper. are aligned with the winding opening of the second roller.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to the drawings. 1 to 4 are displacement diagrams of the sheet paper according to the present invention in a running state. 2 in the figure is the first roller, and this first roller
The roller 2 is equipped with a one-way clutch 3, and the one-way clutch 3 allows the first roller 2 to rotate only in the direction of arrow A, in other words, only in the direction in which the sheet paper 8 is fed. . Further, a pressing member 5 is pressed against the first roller 2 by a spring 6, and works together with the first roller 2 to feed the sheet paper 8. In the figure, 10 is a second roller, and like the first roller 2 described above, a pressing member 11 is pressed by a spring 12. Note that various shapes can be applied to the pressing members 5 and 11,
Of course, a roller may also be used. These first and second rollers 2 and 10 are connected via a transmission means to a motor (not shown) that is controlled to rotate in forward and reverse directions, and the first roller 2 is driven to rotate in the counterclockwise direction (direction A) in the figure. When the second roller 10 is rotated clockwise (direction B), the second roller 10 is connected to rotate in the direction in which the sheet paper 8 is fed.

The operation will be explained below. FIG. 5 is a time chart diagram of the motor, rollers 2, 10, sheet paper 8, and FIGS. 1 to 4. In these figures, the first roller 2 is rotated in the A direction and the second roller 10 is rotated in the B direction by normal rotation of the motor, and the sheet paper 8 is fed. When the sheet paper 8 has been wound around the second roller 10 by a certain amount α, the motor is controlled to stop. (See FIG. 2) Next, the motor is once controlled in reverse to rotate the second roller 10 in the direction of arrow C. At this time, the rotation of the first roller 2 is stopped by the one-way clutch 3. Therefore, only the leading end of the sheet paper 8 is rewound and the leading end is bent as shown in FIG. 11 and line of contact 15. At this point, when the motor is controlled to rotate normally again, the sheet paper 8 is taken into the second roller 10 with its leading edge portions aligned, and the sheet paper 8 is fed without being skewed. (See Figure 4)

[
0008

As described in detail above, according to the present invention, the one-way clutch that rotates only in the paper feeding direction is provided on the front roller of the pair of rollers with respect to the paper feeding direction, Once a predetermined amount of the leading edge of the sheet paper has been taken in by the other roller, the roller is reversed, and the leading edge of the sheet paper is aligned with the roller's intake opening before being taken in again, which prevents the sheet paper from running skewed. Furthermore, it has various effects such as being applicable to various sheet papers of different thicknesses and being highly versatile.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the operation of a mechanism according to the present invention.

FIG. 2 is an explanatory diagram of the operation of the mechanism according to the present invention.

FIG. 3 is an explanatory diagram of the operation of the mechanism according to the present invention.

FIG. 4 is an explanatory diagram of the operation of the mechanism according to the present invention.

FIG. 5 is a time chart diagram illustrating the operation of the mechanism according to the present invention.

[Explanation of symbols]

2 First roller 3 One-way clutch 8 Sheet paper 10 Second roller

Claims (1)

[Claims] 1. First and second rollers, in which the feeding direction of the sheet paper and its rotation axis are arranged at right angles to each other, and are spaced apart from each other; It consists of a pressing member that feeds the sheet paper, and a motor that is controlled to rotate in forward and reverse directions to rotate both of the rollers. Of the two rollers, the first roller on the near side with respect to the feeding direction of the sheet paper feeds the sheet paper. It is equipped with a one-way clutch that rotates only in the feeding direction, and when the leading edge of the sheet of paper wraps around the drive roller by a predetermined amount, the second roller is reversed, and the leading edge of the sheet of paper is released from the second roller. A sheet paper traveling mechanism characterized in that both rollers are rotated in the normal direction again at the point when the paper is rotated.