JPH0411116B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a feed roller and a presser roller for an ink ribbon cassette to be installed in a printer or the like used as a computer terminal.

(Prior Art) An ink ribbon cassette has a built-in device for transporting and folding the ink ribbon. As such devices, feed rollers and pressure rollers made of compressed polyurethane foam or the like are generally used. Such a roller is constructed by punching out a sheet of compressed polyurethane foam or the like into a ring shape and assembling a required number of rollers of appropriate thickness onto a shaft in accordance with the width of the ribbon. For example, Fig. 4 shows the feed roller 11 and presser roller 12 in a conventional ribbon cassette. When the ribbon width is 13 mm, the feed roller 11 has a thickness of 4.5 mm, an outer diameter of 20 mm, and an inner diameter of 20 mm. 13mm
The pressure roller 12 has a thickness of
Two rollers with a diameter of 4.5 mm, an outer diameter of 16 mm, and an inner diameter of 8 mm.
It is constructed by being assembled to a shaft 14.

(Problem to be solved by the invention) In order to construct the feed roller and presser roller as described above, it is necessary to punch out many individual rollers, which increases the processing cost and the material cost of the individual rollers. Therefore, it has been difficult to provide inexpensive feed rollers and presser rollers.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a feed roller and a presser roller for an ink ribbon cassette, which can reduce material costs and processing costs.

(Means for Solving the Problems) In order to achieve the above object, the method for manufacturing the feed roller and presser roller of the ink ribbon cassette in the present invention includes a sheet of soft or semi-hard rubber or foam sheet such as polyurethane. or punching out the compressed foam sheet in concentric circles to simultaneously form two small-diameter and large-diameter rollers, one of which has an outer diameter equal to or less than the other's inner diameter;
The present invention is characterized in that the feed roller and presser roller are constructed by assembling a required number of these small-diameter and large-diameter rollers, each corresponding to the width of the ink ribbon.

(Example) Figures 1 to 3 relate to an example of the present invention. First, Figure 1 shows an ink ribbon cassette 1 equipped with a feed roller 3 and a presser roller 4 manufactured using the manufacturing method of the present invention. This diagram schematically shows the entire interior of the ink ribbon, in which a pair of feed rollers 3 and presser rollers 4, which are made of compressed polyurethane and have the function of transporting and folding the ink ribbon 2, are arranged at one end. has been done.

Next, Figure 2 shows the assembled state of the feed roller 3 and presser roller 4. The feed roller 3 has a thickness of 3 mm, an outer diameter of 20 mm, and an inner diameter of 15 mm.
Three single rollers made of compressed polyurethane 5
is assembled to the feed shaft 6, and the presser roller 4 has a thickness of 3 mm and an outer diameter of
Three rollers 7, also made of compressed polyurethane, each having a diameter of 15 mm and an inner diameter of 8 mm are assembled to a presser shaft 8. The ink ribbon 2 to be transported and folded by the feed roller 3 and presser roller 4 is intended to have a width of 13 mm.

FIG. 3 shows the manufacturing process of the roller unit 5 for the feed roller and the roller unit 7 for the presser roller. That is, two annular bodies are simultaneously formed by punching out the compressed polyurethane sheet 9 three times concentrically, and the annular body with the largest diameter is used as the single roller 5 for the feed roller.
The inner annular body is used as a single roller 7 for a presser roller. Note that the core 10 at the center is discarded.

By the way, the reason why the thickness of the rollers 5 and 7 formed in the above embodiment was set to 3 mm, which is smaller than the conventional 4.5 mm, is as follows. In other words, when a foam sheet with a thickness of about 4.5 mm is punched out, the outer diameter of the annular body is not uniform in the axial direction due to the ease of deformation of the material, resulting in a tapered shape as shown in Figure 5 A. Furthermore, the outer surface of the foam must be polished in a centerless manner to create a single roller 15 with a uniform outer diameter as shown in FIG. , if the material has to be punched with a grinding allowance in mind, and therefore the inner diameter of one annular body and the outer diameter of another annular body are close to each other,
It becomes practically impossible to punch out two annular bodies concentrically at the same time. Therefore, it is necessary to set the thickness within the necessary range (2 to 3 mm) in order to suppress the amount of change in the outer diameter of the annular body caused by punching to a level that does not cause any problems. For example, the outer diameter is 20
mm, and the thickness is 4.5 mm, the axial diameter difference is 0.5 ~
The diameter difference in the axial direction can be suppressed to 0.1 mm or less when the thickness is within the range of 2 to 3 mm.

(Operations and Effects) The present invention is as described above, and a sheet of soft or semi-hard foam such as rubber or polyurethane or a compressed sheet of the foam sheet is punched out concentrically, and one outer side is punched out. By simultaneously forming two small-diameter and large-diameter rollers whose diameter is less than the inner diameter of the other, and by assembling the required number of these small-diameter and large-diameter rollers in correspondence with the width of the ink ribbon, the feed is created. Since the roller and presser roller are each configured, there is no need to punch out multiple rollers separately as in the past, which reduces processing costs, and the material sheet for the roller is used instead of wasted parts. Since this eliminates the problem, material costs can also be reduced, which has the effect of providing inexpensive feed rollers and press rollers. In addition, if the thickness of each roller is set to about 2 mm to 3 mm as in the above example, the outer diameter will be approximately uniform, so the above polishing process that was conventionally performed will be unnecessary, and the processing cost will be reduced. This has the advantage of further reducing the Specifically, compared to constructing the conventional roller shown in FIG. 4, when constructing the roller as shown in FIG. 2 according to the present invention, the overall cost can be reduced substantially. We achieved a remarkable effect of reducing the amount to 1/3 to 1/4.

[Brief explanation of drawings]

1 to 3 are related to the present invention, and the first
The figure is a plan view schematically showing the entire interior of an ink ribbon cassette equipped with a feed roller and a presser roller manufactured using the manufacturing method of the present invention.
Figure 2 is a side view with half of the feed roller and presser roller assembled, and Figure 3
The figure is a plan view of a single roller punched out during the manufacturing process. Also, Figures 4 and 5 relate to a conventional example, where Figure 4 is a side view with half of the feed roller and presser roller assembled in cross section, and Figure 5 is a punched-out diagram of the roller alone. It is a processing process diagram from to polishing. 1... Ink ribbon cassette, 2... Ink ribbon, 3... Feed roller, 4... Presser roller, 5... Single roller for feed roller, 6... Feed shaft, 7... Single roller for presser roller. , 8...presser shaft, 9...
... Compressed polyurethane sheet, 10... Core,
11... Feed roller, 12... Presser roller, 13... Feed shaft, 14... Presser shaft, 15... Conventional roller alone.

Claims (1)

[Claims] 1. Punch out a soft or semi-hard foam sheet of rubber or polyurethane, or a compressed sheet of the foam sheet, in a concentric shape, and then punch out two sheets with a small diameter and a large one, the outer diameter of one of which is less than the inner diameter of the other. An ink ribbon cartridge characterized in that a feed roller and a presser roller are formed by simultaneously forming rollers of a large diameter and assembling a required number of small and large diameter rollers in correspondence with the width of the ink ribbon. A method of manufacturing a set feed roller and presser roller.