JPS6251543A - Paper feed mechanism of printer - Google Patents

Abstract

PURPOSE:To transmit the rotary motion of a platen directly to a pressure roller by mounting rotation transmitting means to a rotary shaft fixed to the pressure roller. CONSTITUTION:A rotary shaft 16 is rotated according to rotation of a friction roller 5, and a pressure roller 4 is rotated. The pressure roller 4 and the friction roller 5 have the same outside diameter, and the rollers are fixed to the same rotary shaft 1, so that the respective peripheral surface speeds are the same and equal. According to rotation of a friction roller 14, a rotary shaft 15 is rotated, and in its turn a pressure roller 13 is rotated. The pressure roller 13 and the friction roller 14 have the same outside diameter, and the rollers are fixed to the same rotary shaft 15, so that the respective peripheral surface speed are kept equal to each other. Accordingly, the peripheral surface speed of a platen 1 and the peripheral surface speeds of the pressure rollers 4, 13 are the same and equal to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper feeding mechanism for a printer, and more particularly to a pressing mechanism for a pressure roller that presses printing paper against the peripheral surface of a platen.

[Prior Art] Conventionally, in this type of paper feeding mechanism, a rotatable pressure roller rotates a platen pressed against the circumferential surface of the platen, pinches the printing paper between the circumferential surface of the platen and the pressure roller, and prints the following paper. It was sent to the organization.

[Problems to be Solved] However, in this conventional paper feeding mechanism, the pressure roller pressed against the circumferential surface of the platen through the printing paper is frictionally moved by the rotation of the platen. The disadvantage is that the pressing force of the pressure roller cannot be reduced. Furthermore, since the pressing force of the pressure roller acts as a resistance to the rotation of the platen, there is also the drawback that the rotational force of the platen must be ensured. Furthermore, since the pressure roller obtains driving force through frictional force from the circumferential surface of the platen or the paper surface of the printing paper, the frictional force between the pressure roller and the circumferential surface of the platen or the paper surface of the printing paper decreases at low temperatures, resulting in However, there is a drawback that printing paper cannot be sent out stably.

[Means for Solving the Problems] In order to solve the above-mentioned conventional problems, the present invention provides a paper feeding mechanism for a novel printer that directly transmits the rotational motion of the platen to the pleasure roller.

To this end, the present invention provides a rotation mechanism that directly transmits the rotational motion of the platen to a fixed rotating shaft of the pressure roller in a paper feeding mechanism of a printer that feeds printing paper using a platen and a pressure roller pressed against the platen circumferential surface. The present invention provides a paper feeding mechanism for a printer, characterized in that it is equipped with a transmission means.

[Example code] Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a plan view of an embodiment of the paper feeding mechanism of the present invention. FIG. 2 is a plan view from the embodiment of FIG. 1 with the platen and guide plate removed. FIG. 3 is a left side view of the embodiment shown in FIG. 1, and FIG. 4 is a XX sectional view thereof.

Reference numeral 1 denotes a platen, which sends out printing paper 17 supplied through area A with guide plate 2 to a subsequent mechanism. 3 is a motor fixed to the housing, and a gear 11 fixed to an output shaft 19 is connected via a two-stage gear 10 and a gear 9 to a gear 8 fixed to the rotating shaft 21 of the platen 1. Pressure rollers 4 and 13 are fixed to rotating shafts 15 and 16, respectively, and press the printing paper 17 against the circumferential surface of the platen 1. 5.14 are the rotating shafts 15, respectively.
．． A friction roller fixed to one end of the platen 16 and having its circumferential surface in contact with the circumferential surface of the platen 1 transmits the rotational movement of the platen 1 to the pressure roller 4.13 by stable frictional force. The outer diameter of the friction rollers 5.14 is equal to the outer diameter of the pressure rollers 4, 13, respectively. A support plate 6 is placed on a shaft 7 whose both ends are pivotally supported by the housing, and supports at one end a roller support 12 which rotatably supports the rotating shafts 15 and 16. A coil spring 18 has one end locked to the housing and the other end locked to the other end of the support plate 6, and the pressure roller 4.
13 ensures the pressing force of the printing paper 17 against the circumferential surface of the platen 1.

Start motor 3 and transfer its rotational output to gear 11゜10.9
．． 8 to the rotating shaft 21 of the platen l. As the platen 1 rotates, the friction roller 5.14 that is in contact with its peripheral surface is also rotated.

Therefore, the peripheral surface speed of the platen 1 and the peripheral surface speeds of the friction rollers 5 and 14 are maintained the same. In accordance with the rotation of the friction roller 5, the rotating shaft 16 is rotated, which in turn rotates the pressure roller 4. Since the pressure roller 4 and the friction rollers 5 have the same outer diameter and are fixed to the same rotating shaft 16, their circumferential surface speeds are maintained equal to each other. In accordance with the rotation of the friction roller 14, the rotating shaft 15 is rotated, and in turn, the pressure roller 13 is rotated. Since the pressure roller 13 and the friction roller 14 have the same outer diameter and are fixed to the same rotating shaft 15, their circumferential surface speeds are maintained equal to each other.

Therefore, the circumferential speed of platen l and pressure roller 4.1
The circumferential surface speeds of No. 3 and No. 3 are maintained equal to each other. As a result, the printing paper 1 is supplied from the area A by the guide plate 2.
7 is pressed and delivered by the circumferential surface of the platen 1 and the circumferential surface of the pressure roller 4.13, the pressure roller 4.13 hardly acts as resistance against the circumferential surface of the platen 1.

In the above description, a friction roller that is in contact with the circumferential surface of the platen is used as a rotation transmission means for directly transmitting the rotational motion of the platen to the pressure roller. Other means such as interlocking gears may also be employed.

[Effects of the Invention] As is clear from the above, the present invention has the effect of reducing the pressing force of the pressure roller against the peripheral surface of the platen because the rotational movement of the platen is directly transmitted to the pressure roller by the rotation transmission means. This, in turn, has the effect of reducing the rotational driving force of the platen. Therefore, the present invention
This has the effect of reducing the size of the platen drive motor and reducing manufacturing costs. Furthermore, the present invention directly transmits the rotational motion of the platen to the pre-7 shear roller, so it has the effect of stably feeding the printing paper even at low temperatures. Therefore, the present invention has the effect of providing a highly reliable printer or paper delivery mechanism.

[Brief explanation of the drawing]

FIG. 1 is a plan view of one embodiment of the paper feed mechanism of the present invention, FIG. 2 is a plan view with the same portion omitted, FIG. 3 is a left side view of the same, and FIG. 4 is a xx sectional view of the same. 1 Nibraten 2: Guide plate 3: Motor 4.13: Pressure roller 5.14: Friction roller 6: Support plate 7: Shafts 8 to 11: Gear 12: Roller support 15.16.21: Rotating shaft 17: Printing paper 18 :Coil spring 19:Output shaft

Claims (1)

[Claims] In a paper feeding mechanism of a printer that feeds printing paper using a platen and a pressure roller pressed against the platen circumferential surface, a rotation transmission means is installed to directly transmit the rotational motion of the platen to a rotating shaft fixed to the pressure roller. A paper feed mechanism for a printer characterized by: