JPS62244642A - Printing drum for printer - Google Patents

Abstract

PURPOSE:To obtain a printing drum for a printer having excellent accuracy and good production efficiency and capable of attaining cost reduction to a large extent, by constituting said drum of a type plate having type parts punched by the press processing of a metal plate and a cylindrical core and winding the type plate around the core to integrally bond both of them. CONSTITUTION:Types 30 are formed to a thin metal plate by punching said metal plate by press processing, for example, semi-punching processing or coining processing to form a type plate 31 which is, in turn, wound around a cylindrical core 40 to be integrally bonded thereto. By this method, productivity is made excellent and cost reduction is attained to a large extent. Because the types are formed by press processing, the width of each type is constant. As a result, because the grinding of the outer peripheral surface of each type is enabled, the degree of concentricity and that of cylindricalness can be secured and the number of component parts can be reduced.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a print drum for a printer.

[Prior Art] A conventional printing drum for a printer has a structure as shown in FIGS. 7 to 9. Here, Fig. 7 is a sectional view, and Fig. 8 is a sectional view.
The figure shows a developed view of the type surface, and FIG. 9 shows an enlarged perspective view of the type. In other words, the type drum cylinder on which printed characters such as numbers, symbols, and letters as shown in FIGS. 7 and 8 are formed on the surface. Bushes 20 and 21 are press-fitted into the inner diameter portions of both ends of the body 11.

By the way, conventionally, the type drum cylindrical body 11 is.

It is manufactured by turning a blank and then rolling it with a die to raise up the 10 parts of the type, or by photo-etching to leave the 10 parts of the type.

[Problems to be solved by the invention] In the rolling method, the width of the type and the precision of the outer periphery of the type surface vary, and the cross section of the type LO is formed into a trapezoid, so the outer periphery must be polished to achieve cylindricity. When you do this, the type width changes. In addition, bushings 20 and 21 are necessary to ensure the concentricity between the rotating shaft (not shown) and the face of the type 10. Since it is necessary to correct the center holes of bushes 2o and 21 based on the surface, there are many processing steps.
The cost will be high. Furthermore, since the bushings 2o and 21 are required, the number of parts increases, which also increases the cost.

The photoetching method has no problems with accuracy, but
This method is not used at present because the processing equipment costs are high and the cost is inevitably high.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing drum for a printer that has excellent accuracy, good production efficiency, and can significantly reduce costs.

[Means for Solving the Problems] The problem with the above-mentioned conventional technology is that it consists of a type plate in which type parts are stamped out by pressing a metal plate and a cylindrical core. This can be solved by wrapping it around and joining it together.

[Example] An example of the present invention will be described below with reference to FIGS. 1 to 3. As shown in FIG. 2, a type plate 31 is manufactured by stamping out typefaces 30 by pressing, for example, half punching or coining, a thin metal plate with a thickness of 0.2 to 0.3 mm. As shown in Fig. 1, one cylindrical core metal 40
It is wrapped around and joined together.

Since the type 30 is pressed out in this way, the width of the type is the same from the base to the tip. Therefore, even if the outer periphery of the 30 types is polished in order to ensure the cylindricity of the 30 types, the width of the type does not change.In other words, even if there is some variation in the height and concentricity of the 30 types, the core metal 40 It is possible to polish the outer periphery of the 30 faces of the type based on a rotating shaft (not shown) that is press-fitted into the hole, and it is possible to ensure concentricity and cylindricity. In addition, there is no need to fix bushings at both ends to ensure concentricity and correct boring of the center hole based on the typeface, as in conventional rolling processing, and the number of parts can be reduced. In particular, as shown in FIG. 4, the rotating shaft portion 41 can be formed integrally with the core metal 40, and the number of parts can be further reduced.

The type plate 31 and the metal core 40 are joined together, for example, by the following method.

The first method, as shown in FIG. 5, is to wrap the type plate 31 around the outer circumference of the core metal 40, and then join the two ends of the type plate 31 and the contact surface of the core metal 40 at multiple locations by welding. .

In the second method, the core bar 40 is plated with brazing material in advance, the type plate 31 is wrapped around the outer periphery of the core bar 40 as in the first method, and then the type plate 31 and the core bar are wrapped. 40 and then heated and brazed.

As shown in FIG. 6, the third method involves forming the type plate 31 into a cylindrical shape in advance, welding the ends to form a cylindrical body, and press-fitting the core metal 40 into the cylindrical type plate 31. do.

The fourth method is to manufacture the cylindrical type plate 31 as explained in the third method, plate the core bar 40 with brazing material in front, and then attach the core plate 31 to the core plate 31. 40 is press-fitted, then heated and brazed.

[Effects of the Invention] As is clear from the above description, according to the present invention, a type plate is manufactured by pressing a metal plate and printing type, and the type plate is wound around a core metal and integrated. Since it is made by joining, it has superior productivity compared to conventional structures and can significantly reduce costs. Furthermore, since the type is formed by press working, the width of the type is constant. Therefore, since the outer periphery of the typeface can be polished, concentricity and cylindricity can be ensured, and the number of parts can be reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
The type plate shown in the figure is shown, (a) is a top view, (b) is a bottom view,
FIG. 3 is an enlarged sectional view of the type portion shown in FIGS. 1 and 2, FIG. 4 is a sectional view showing another embodiment of the present invention, and FIGS. 5 and 6 are the printing drum shown in FIG. 1, respectively. 7 is a sectional view of the conventional example, FIG. 8 is a developed view of the typeface of FIG. 7, and FIG. 9 is a view of the typeface of FIGS. 7 and 8. FIG. 30: Type, 31: Type board, 40: Core metal. Figure 1 Figure 2 Figure 4 Figure 115 Figure 1

Claims (1)

[Claims] A type plate where the type part is stamped out by pressing a metal plate,
1. A printing drum for a printer, comprising a cylindrical metal core, the type plate being wrapped around the core metal and integrally joined.