JPS6280071A - Paper-feeding mechanism for printer - Google Patents

Abstract

PURPOSE:To prevent double printing on the same part or damaging of a platen from occurring even on the occurrence of a paper jamming, by setting the diameter of a platen to be small so that the velocity at which a paper is fed by the platen is lower than the velocity at which the paper is fed by a tractor. CONSTITUTION:A printing paper 10 is fitted to a tractor 5, and is pressed against a platen 4 by a paper guide 11 on the lower side. With a motor 1 rotated by a predetermined amount, the turning force is transmitted to a tractor 7, and the paper is securely fed out by a required amount at a time. Simultaneously, the turning force transmitted to the platen 4 functions to feed the paper 10 upward by friction generated at the periphery of the platen 4. Since the diameter of the platen 4 is set to be small so that the quantity of feed by the platen is smaller than the quantity of feed by the tractor 7, the paper is maintained in a slightly stretched state, and it is printed at a printing position in the stretched state. Accordingly, the paper will not sag, it is not fed in excess even when the platen 4 overruns, and double printing at the same part or damaging of the platen can be prevented from occurring even on the occurrence of a jamming.

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 paper feeding mechanism for a printer characterized by a transmission system between a motor, a platen, and a tractor.

[Conventional technology]

1 a car? In the case of a winter Senda eggplant printer, the platen is either fixed and made of a hard material with a low coefficient of friction, such as metal, or the platen is rotated and its surface is coated with rubber or resin. It was divided into two types: those with a high coefficient of friction;

Moreover, when rotating, the rotational speed of the outer circumference of the platen was made to match the paper feeding speed of the tractor.

[Problems to be solved]

In the case of the above-mentioned conventional platen fixation, when a paper jam occurs for some reason, the same place on the platen has to be printed over and over again, resulting in damage to the platen. For this reason, if a hard material such as metal is used for the platen, depending on the material, it may cause damage to the hammer side, and the selection of the platen hardness is extremely difficult. In addition, when the platen is fixed, a large frictional force is generated between the paper and the platen, resulting in misalignment between the top and bottom of each sheet, and damage to the feed hole, resulting in a paper jam. On the other hand, when the platen is rotated, the platen itself is heavy, and the demand for rotating it at higher and higher speeds creates a large inertial load, which requires a larger motor than when the platen is fixed. In addition, when rotating, the platen cannot be stabilized in a short period of time due to play and elastic deformation that occurs in the transmission system, making it difficult to obtain a high printing ln4 degree.Furthermore, the overrun of the platen causes the paper to overlap with the tractor. This caused a bulge and caused noise.

[Means for solving problems]

The present invention has been made by focusing on the above-mentioned conventional problems.
This eliminates paper bulges, reduces noise, and stabilizes the print position. This reduces the load on the motor, speeds up the settling time of the platen, provides highly accurate print position, and prevents jams. The purpose of the present invention is to provide a printer's paper feed + A hole that can avoid printing on the same spot and damaging the platen and L even if such occurrence occurs.

To this end, the present invention provides a paper feed mechanism for a printer in which a gear or a pulley attached to one end of the shaft of a motor, which is a force source, and a platen and a tractor are connected by a series of gear trains or a direct belt. This invention provides a paper feeding mechanism for a printer characterized in that the diameter of the platen is set to be small so that the paper feeding speed is slower than the paper feeding speed by a tractor.

C Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an embodiment of the present invention. motor l
A shaft Kfi pulley 2 is attached and connected via a platen belt 3 to a platen 4 and a platen pulley 5 which is rotatably attached. On the other hand, the tractor belt 6 is connected to a tractor pulley 9 attached to a tractor shaft 8, which is a small moving shaft of a tractor 7. Here, the diameter of the platen 4 is set to be small so that the speed at which the paper is fed by the platen 4 is slower than the speed at which the paper is fed by the tractor 7. The printing paper 10 is mounted on the tractor 5 and is pressed against the platen 4 by a paper guide 11 below.

Now, when the motor 1 rotates by a desired amount in the direction of the notch in the figure, the rotational force is transmitted to the tractor 7, which reliably feeds out the paper by the required amount. At the same time, the rotational force transmitted to the platen 5 sends the print paper 10 upward due to the friction generated on its outer periphery, but the feed end is made smaller by 1 mm and smaller than the operating amount of the tractor 5. Therefore, the paper is always in a slightly stretched state, and printing is always done in a taut state at printing position 4'. Therefore, the paper does not bulge, and even if the platen 4 overruns, no extra paper is sent, and even if a jam occurs, the VC does not print in the same place or damage the platen. Although this embodiment shows an example, the present invention is not limited to this, and the platen and the tractor may be connected by a series of gear trains.

〔Effect of the invention〕

As explained above, the present invention provides a paper feed mechanism for a printer in which a gear connected to one end of the shaft of a motor, which is an effect source, is connected to a pulley, a platen, and a tractor by a series of gear trains or a direct belt. The paper feed mechanism of the printer is characterized by a platen diameter set to be smaller so that the paper feed speed is slower than the paper feed speed by a tractor.
By reducing the diameter of the platen, paper bulges are eliminated, noise is reduced, and the printing position is stabilized.The platen is also lighter, reducing the load on the motor, and the motor itself has a lower output and is less expensive. Be able to use things.

On the other hand, since the amount of movement of the platen is smaller than the amount of movement of the printing paper, even if slippage occurs between them and the platen slightly overruns, the paper will not be fed out unnecessarily. It will be done.

In addition, since the platen itself is rotating, even if a paper jam occurs, printing will not be performed on the same spot on the platen, and there is no need to damage the platen. Materials such as rubber can be used to prevent damage to the platen. The effects can still be passed on.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention. 1... Paper feed motor 2... Pulley 3... Platen belt 4... Platen 5... Platen pulley 6... Tractor belt 7... Tractor
8...Tractor shaft 9...Tractor taboo IJ 10...1 printing paper 0e Vapor guide agent Patent attorney Mura 1) Yu Miki Figure 1

Claims (1)

[Claims] In the paper feed mechanism of a printer, in which a gear or pulley attached to one end of the shaft of the motor, which is the power source, and the platen and the tractor are connected by a series of gear trains or a direct belt, the paper feed speed by the platen is slower than the paper feed speed by the tractor. A paper feed mechanism for a printer characterized in that the diameter of the platen is set to be small so as to