JPH0717086A - Platen for small-sized impact dot printer - Google Patents

Abstract

PURPOSE:To provide an ideal platen at low cost, which makes low printing noise, can be shaped freely, and has impact resistance and bending strength. CONSTITUTION:A platen for small-sized impact dot printer comprises a metallic plate 2, a plastic plate 1 molded by adding fine metallic powder at a fixed density, and an adhesive member for adhering and fixing the metallic plate 2 and the plastic plate 1. By using the plastic plate 1 which contains the metallic powder as a platen, impact resistance with dot pin and damping effect are made to be compatible with each other, and the platen can be shaped freely. Further, by adhering and fixing the metallic plate 2, the impact resistance and the damping effect are also provided. As cutting and rubbing are not necessary, the cost can be reduced, thereby providing an ideal platen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small printer, and more particularly to a platen for a small impact dot printer.

[0002]

2. Description of the Related Art Conventionally, in this type of technique, a metal plate is bent as shown in FIG. 2 and used as a single platen, or a plastic platen integrally formed with a body frame is used.

[0003]

However, in the above-mentioned prior art, when a metal plate is used alone, a thin metal plate produces a loud print noise, and a thick metal plate is difficult to be bent to form a shape. The cutting / polishing process was inevitable in order to achieve the extremely important flatness of the platen surface, resulting in high costs. In order to avoid such high cost, there is no choice but to make it into a non-bending shape, and it is impossible to form a side surface guide of printing paper or the like, which has unevenness necessary for the platen to have many functions.

Further, when a plastic platen integrally formed with the frame is used, the printing sound becomes loud and the hitting strength and bending strength by the head are insufficient, so that it is difficult to secure the durability and the platen gap.

The present invention has been made to solve such drawbacks, and its purpose is to be inexpensive, to produce small print noise, to have flexibility in shape, and to be struck and bent. It is to provide an ideal platen with a certain size.

[0006]

A platen for a compact impact dot printer according to the present invention comprises a metal plate, a plastic plate formed by containing fine metal powder at a constant density, and the metal plate and the plastic plate bonded together. It is characterized by being constituted by an adhesive member for fixing.

[0007]

1 is an exploded perspective view of a platen according to an embodiment of the present invention. 1 is a plastic plate, 2 is a metal plate, 3
Is a double-sided adhesive tape for adhering and fixing the plastic plate 1 and the metal plate 2. The plastic plate of No. 1 contained about 80 percent by weight of Fe powder, and the base plastic was polyamide resin. The material of the metal plate 2 is SUS. As shown in FIG. 3, a platen composed of these three elements is fixed to a fixed frame 4 with a screw 5, and a print head 8 is attached to the platen via a print paper 8 and an ink ribbon 7 which are fed in close contact with the platen. It is installed so as to face each other with a certain distance.

In the printing operation, by applying a current to the print head 6, the dot pin 9 is pushed out toward the platen,
This is performed by sandwiching the ink ribbon 7 and the printing paper 8 with a platen and the dot pins 9 and transferring the ink of the ink ribbon 7 to the printing paper 8. At this time, a strong pressing force is instantaneously applied to the platen. This energy radiates as sound. It is generally known that this sound energy can be reduced by using a material having a large internal loss, but such a material is generally soft and is likely to undergo elastic deformation or plastic deformation. When the platen of the dot impact printer is used as it is, the pressing force of the dot pin 9 causes fine scratches on the platen surface.

The material of the plastic plate 1 used for the platen of the present invention is polyamide, which is a base polymer having a large internal loss characteristic and contains Fe powder having a high hardness, and is integrally molded so that the impact strength against the dot pin 9 can be improved. It is possible to achieve both of the contradictory characteristics of reducing the sound while securing the sound. However, when the Fe content is less than 70% by weight, the effect on hitting strength becomes less, and when the weight ratio is more than 90%, the material itself becomes brittle, and the deformation of Fe due to oxidation or the printing paper becomes difficult. As dirt is generated,
Not suitable for use. Therefore, the content of the Fe powder is optimally 70 to 90% by weight.

Further, since the plastic plate 1 has a weak bending strength, if it is used as it is for the platen, it will be bent and vibrated by the pressing force of the dot pin 9. Therefore, in the present invention, the metal plate 2 is adhered and fixed to the plastic plate 1 with the double-sided adhesive tape 3 to provide a two-body structure with bending strength. Further, the metal plate 2 leads to an increase in the weight of the entire platen and also has a silent effect.

[0011]

As described above, according to the present invention, by using a plastic plate containing metal powder for the platen, both the hitting strength by the dot pin and the silent effect are achieved, and the flexibility of the shape is also provided. Further, by bonding and fixing the metal plate, bending strength and noise reduction effect can be provided. In addition, since there is no need for cutting or polishing, the cost is low and an ideal platen can be provided.

[Brief description of drawings]

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

FIG. 2 is a perspective view showing an example of a conventional technique.

FIG. 3 is a side view showing an embodiment of a printing mechanism using the present invention.

[Explanation of symbols] 1 plastic plate 2 metal plate 3 double-sided adhesive tape 6 print head 9 dot pin

Claims (3)

[Claims] 1. A small size characterized by comprising a metal plate, a plastic plate formed by containing fine metal powder at a constant density, and an adhesive member for adhering and fixing the metal plate and the plastic plate. Impact dot printer platen. 2. The platen for a small impact dot printer according to claim 1, wherein the material of the metal powder is Fe and the material of the plastic is polyamide. 3. The plastic plate according to claim 2, wherein F
The weight ratio of e to polyamide is Fe: polyamide = 9: 1 to
The platen for a compact impact dot printer according to claim 1 or 2, wherein the platen is 7: 3.