JPS6271670A - Platen for impact-type printer - Google Patents

Abstract

PURPOSE:To absorb sounds generated on a platen and reduce noise, by providing a cavity-forming member which provides a multiplicity of cavities extending in the axial direction of a platen, between the inner periphery of a platen surface layer member and the outer periphery of a rotary shaft. CONSTITUTION:A platen comprises a rotary shaft 11, a cavity-forming member 14 and a platen surface layer member 15 as essential component members. The cavity-forming member 14 is formed of aluminum (which is the material for the rotary shaft 11), a plastic or rubber, and comprises an inner cylindrical part 14a, an outer cylindrical part 14b and partition walls 14c radially bridging therebetween, as one body. Therefore, a multiplicity of cavities 14d defined by the inner cylindrical part 14a, the outer cylindrical part 14b and the partition walls 14c are extended in the axial direction of the platen. The inner periphery of the cavity-forming member 14 is fixed onto the outer periphery of the rotary shaft 11 by press fitting or the like. In this platen, the impact sounds generated on the platen surface layer member 15 at the time of a printing operation of a printer are attenuated through absorption thereof into the cavities 14d in the cavity-forming member 14.

Description

[Detailed description of the invention] [Technical field] The present invention relates to a platen for an impact printer.

[Background Art] Printers are classified into impact type and non-impact type depending on the printing method. Each of these types has its advantages and disadvantages, but when looking at the amount shipped in 1988, the impact type accounted for 88% of the total. (According to research by the Japan Electronics Industry Promotion Association) The major drawbacks of the currently mainstream impact printers are that they do not hit the type violently through the ink ribbon, or have printing wires that protrude, printing onto plain paper on the platen. The problem is that there is a lot of noise when printing characters.

In a conventional serial impact printer, as schematically shown in FIG. 4, the platen l is formed of rubber or aluminum into a cylindrical shape, and its inner circumferential body is fixed to the outer circumferential side of the rotating shaft 2 by press fitting or the like. are doing.

3 is an ink ribbon, 4 is, for example, a printing wire, and 5 is plain paper. That is, in the past, little consideration was given to the sound generated on the platen l. Such a platen is also used in line impact printers.

[Object of the Invention] The present invention has been made in view of the above reasons, and its purpose is to provide a platen that can reduce the noise of an impact printer by absorbing the sound generated on the platen. There is something to do.

[Disclosure of the Invention] The platen of the impact type printer according to the present invention has a printing stand formed in a cylindrical shape made of hard rubber around the outer periphery of a rotating shaft, and the printing stand is connected to the inner circumferential cylinder of the printing stand. It is characterized by interposing a cavity forming member that forms a large number of cavities extending in the axial direction between the outer circumferential shells of the moving shaft.

(Example) An example of the present invention will be described below based on FIGS. 1 and 2.

The platen of the present invention has a rotating shaft 11. The main components are a void forming member 14 and a printing stand 15.

The rotation shaft 11 is made of aluminum or the like and has a cylindrical shape.
The tenon portions 11a at both ends are rotatably supported by the table 12. 13 is a paper feeding member provided near the end of the rotating shaft 11.

The cavity forming member 14 is made of the same material as the rotating shaft 11, such as aluminum, plastic, or rubber, and includes an inner cylindrical portion 14a, an outer cylindrical portion 14b, and a partition wall 14C that radially bridges between them. It is formed. Therefore, the inner cylindrical portion 14a, the outer cylindrical portion 14b and the partition wall 14
A large number of cavities 14d surrounded by C extend in the axial direction.The cavity forming member 14 has its inner circumferential shell fixed to the outer circumferential shell of the rotating shaft 11 by press fitting or the like.

The printing stand 15 is formed of hard rubber into a cylindrical shape, has a length sufficiently larger than the printing range, and has a length that is sufficiently larger than the printing range.
It has a length slightly larger than 4. The printing stand 15 has its inner cylinder fixed to the outer cylinder of the space forming member 14 by press fitting or the like. In this case, the printing table 15 is fixed in such a manner that the space forming members 14 are recessed from both ends thereof substantially equally. Therefore, the space forming member 14 is interposed so that a large number of spaces 14d extending in the axial direction are arranged between the inner circumferential cylinder of the printing table 15 and the outer circumferential cylinder of the rotating shaft 11.

Reference numeral 16 denotes an end plate formed into a disk shape, the outer diameter of which is the same as that of the printing base 1.
5, the inner diameter of the central through hole 16a is the rotation axis 1.
The diameter of each outer circumference is approximately equal to the diameter of the outer circumferential trunk of No. 1. This end plate 16 is fixed to the cavity forming member 14 and the rotating shaft 11 by adhesive or press fitting so as to close both ends of the cavity 14d of the cavity forming member 14.

Such a platen is used as the printing base 15 during the printing operation of the printer.
The pounding sound generated above is attenuated and absorbed by the cavity 14d of the cavity forming member 14. That is, this space 14d acts as a sound absorption box. Note that both ends of the space 14d are connected to the end plate 16.
By closing with , not only does it become difficult for the attenuated sound-absorbed banging sound to leak out, but also the attenuation sound-absorbing effect itself is improved.

FIG. 3 shows another embodiment of the present invention, in which only the structure of the cavity forming member is different from the previous embodiment, and the same members as in the previous embodiment are given the same reference numerals. That is, the cavity forming member 24 of this embodiment has a honeycomb shape in plan view, and a larger number of cavities 24d are formed compared to the previous embodiment, so that the damping sound absorption effect is more pronounced. Become.

[Effects of the Invention] Since the platen of the impact printer of the present invention is configured as described above, it can absorb the sound generated on the platen, and the noise of the impact printer is lower than that of the conventional one. This makes it possible to reduce the

[Brief explanation of drawings]

FIG. 1 is a perspective view of a main part showing one embodiment of the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is a perspective view of a main part showing another embodiment of the invention, and FIG.
The figure is a schematic diagram of a conventional example. 11-rotation shaft, 14-void forming member, 14d-vacuum, 15-printing stand, 16-end plate. Patent Applicant: Matsushita Electric Works Co., Ltd. Representative Patent Attorney: Takemitsu Sanko (and 2 others) Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) A platen for an impact printer in which a printing stand formed in a cylindrical shape made of hard rubber is arranged around the outer periphery of a rotating shaft, and the axial direction is between an inner circumferential cylinder of the printing stand and an outer circumferential cylinder of the rotating shaft. 1. A platen for an impact printer, characterized in that a cavity forming member is interposed to form a large number of cavities extending from one side to the other.