JPH07172615A - Pressure roller device - Google Patents

Abstract

PURPOSE:To provide a pressure roller device capable of making stable sheet pressing action while suppressing the occurrence of snaking and sideslip of a sheet. CONSTITUTION:Pressure roller devices are mounted on the same shaft at specified intervals and provided with at least three pressure rollers 1 to 4 opposedly to a platen roller 10. For pressure rollers 1 and 2 positioned at the center among the respective pressure rollers, pressure rollers for making relatively strong pressing are used. Also tapered pressure rollers 3 and 4 are installed on both sides of the pressure rollers 1 and 2 positioned at the center and, by the action of the tapered pressure rollers 3 and 4, the pressing force of the pressure rollers 3 and 4 positioned at the center functions more effectively and a stabler feed force for sheets such as post card sheets 11, etc., can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure roller device, and more particularly to a pressure roller device for holding a paper, which is installed in a paper feeding portion of a printer or the like.

[0002]

2. Description of the Related Art Conventionally, a roller for pressing a paper, which is equipped in a paper feeding portion of a printer or the like, is composed of only a pressure roller, and only a uniform pressing force acts when pressing the paper.

[0003]

As described above, since the conventional pressure roller exerts only uniform pressing force when pressing the paper, for example, when printing postcard paper or the like, vibration or other external force is applied. There is a problem that the paper is liable to be misaligned or laterally shifted depending on the factor.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pressure roller device which improves the disadvantages of the prior art and can perform a stable paper pressing operation while suppressing the occurrences of paper lag and lateral deviation. To that end.

[0005]

SUMMARY OF THE INVENTION In the present invention, at least three pressure rollers are provided on the same shaft at predetermined intervals and are opposed to the platen roller.
Further, as the pressure roller located at the center of each pressure roller, a pressure roller that presses relatively strongly is used. Furthermore, a pressure roller with a taper is provided on both sides of the pressure roller located in the central portion. This aims to achieve the above-mentioned object.

[0006]

When the platen 10 rotates, the postcard paper 11 is sent out while being pressed by the pressure rollers 1-2 and the tapered pressure rollers 3-4.
In this case, a strong pressing force acts on the intermediate portion of the postcard paper 11, and a weak force by the tapered pressure rollers 3 to 4 acts on both ends. Then, in the tapered pressure rollers 3 to 4, a wedge force acts on the abutting surface to constantly push the postcard paper 11 slightly inward from both sides. Therefore, the pressing force of the intermediate pressure rollers 1 and 2 functions more effectively, and a more stable feed force can be obtained for the paper such as the postcard paper 11.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

1 and 2, reference numeral 10 indicates a platen roller 10, and reference numeral 11 indicates a printing paper such as a postcard. Four pressure rollers 1 to 4 for pressing the paper are provided in contact with the outer periphery of the platen roller 10. Of the pressure rollers 1 to 4, the pressure rollers 1 and 2 located in the central portion are configured as pressure rollers that press down relatively strongly. The pressure rollers 3 and 4 located on the outer side are tapered on their outer circumferences. Each of the tapered pressure rollers 3 and 4 is arranged such that its small diameter side faces outward.

Reference numeral 5 indicates each of the pressure rollers 1 to 1.
4 shows a support shaft that supports 4 at a predetermined interval. The entire support shaft 5 is rotatably supported by a holding mechanism (not shown), and is configured to be capable of uniform undulation while maintaining a parallel state with the platen 10 described above. It is equipped so as to be movable left and right along the surface of the platen 10.

Each of the pressure rollers 1 to 4 is made of an elastic member such as rubber, and a urethane-based resin coating film 6 is fixed to each surface thereof. The urethane resin coating film effectively suppresses the generation of paper dust.

When the platen 10 rotates in the direction of arrow A, the postcard paper 5 is sent out while being pressed by the pressure rollers 1-2 and the tapered pressure rollers 3-4.

Therefore, a strong pressing force acts on the intermediate portion of the postcard paper 11, and a weak force by the tapered pressure rollers 3 to 4 acts on both ends. Then, in the tapered pressure rollers 3 to 4, a wedge force acts on the abutting surface to constantly push the postcard paper 11 slightly inward from both sides. Therefore, the pressing force of the pressure rollers 1 and 2 located in the middle functions more effectively, and a more stable feed force can be obtained for the paper such as the postcard paper 11.

Here, in the above embodiment, the case where two pressure rollers located in the central portion are provided is disclosed, but the number of pressure rollers located in the central portion may be one, or three or more. Good.

[0014]

Since the present invention is constructed and functions as described above, according to this, the pressure roller located at the central portion functions more effectively due to the action of the tapered pressure roller, and therefore the paper It is possible to provide an unprecedented excellent pressure roller device capable of performing a stable paper restraining operation while suppressing the occurrence of curling and lateral deviation.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing the tapered pressure roller disclosed in FIG.

[Explanation of symbols]

 1, 2 Pressure Roller 3, 4 Tapered Pressure Roller 5 Roller Shaft 6 Urethane Resin 10 Platen 11 Postcard Paper

Claims (3)

[Claims] 1. A pressure roller comprising: at least three pressure rollers arranged to face the platen roller; and a support shaft supporting the respective pressure rollers on the same shaft at a predetermined interval. The pressure roller located at the center of the pressure roller is a pressure roller that presses relatively strongly, and the pressure rollers located at both ends are tapered pressure rollers, and the small diameter side of each tapered pressure roller is the outside. A pressure roller device characterized in that the pressure roller device is arranged facing toward. 2. The pressure roller device according to claim 1, wherein a urethane resin coating film is provided on each surface of the pressure roller and the tapered pressure roller. 3. The pressure roller made of rubber is used as each of the pressure rollers.
The described pressure roller device.