JPH085189B2 - Wire dot print head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] A wire dot print head having a plurality of print wires supported by a pin guide so as to be able to move back and forth. The print dot quality and copy performance are improved, and the tip of the print wire is not damaged. For the purpose of preventing the above, in a wire dot print head provided with a plurality of printing wires supported by a pin guide so as to be able to move back and forth, the printing wires are connected to the tip of the large diameter portion with a conical connecting portion of the small diameter portion. The print wire is formed by smoothly connecting the print wire through the pin guide and the large diameter portion of the print wire is supported by the pin guide.

[Industrial application field]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire dot print head including a plurality of print wires that are supported by a pin guide so as to move back and forth.

In the wire dot print head, it is necessary to increase the number of print wires (24 pins or more) with the demand for high print quality. Further, it is also required to improve the copy capability for printing on 9P paper and the like. To solve the former requirement, the wire tip diameter must be 0.2 mm or less in order to reduce the effect of overlapping images by adjacent wires.To solve the latter requirement, the surface pressure of the wire tip must be reduced. The wire tip diameter must be 0.2 mm or less in order to improve the copy performance by raising the. That is, in any case, the wire tip diameter needs to be 0.2 mm or less, specifically 0.16 to 0.18 mm.

[Conventional technology]

For this reason, conventionally, the diameter of the printing wire is set to 0.16 to 0.18 mm, and this is supported by the pin guide. The thickness of the pin guide that supports the print wire is about 1 mm, and the diameter of the print wire support hole of the pin guide is about +0.02 mm of the wire diameter.

[Problems to be Solved by the Invention]

However, in the conventional structure as described above, there is a problem in that the tip of the wire is broken due to a lateral force generated by being caught by the running ribbon during printing.

The present invention realizes an improvement in print quality and copy ability,
Moreover, it is an object of the present invention to provide a wire dot print head capable of preventing breakage of the tip of the printing wire.

[Means for solving the problem]

In order to achieve the above-mentioned object, in the present invention, in a wire dot print head which is supported by a pin guide so as to be able to move back and forth and has a plurality of printing wires, the printing wires are connected to the tip of the large diameter portion in a conical shape with a small diameter portion. And a large diameter portion of the printing wire is supported by the pin guide, and the tip of the small diameter portion of the printing wire is the pin guide when not driven. The structure is such that it does not protrude from the end face.

[Action]

Since the small-diameter portion is formed at the tip of the large-diameter portion and printing is performed by the small-diameter portion, it is possible to improve the printing quality by increasing the number of pins. In addition, since the printing is performed with the small diameter portion, the surface pressure at the tip of the wire is increased, and the copying ability is improved.

Further, the small diameter portion is provided only at the tip of the printing wire, and the small diameter portion is connected to the crab body through the conical connection portion with the large diameter portion, which is a breakage point that has been a problem in the past. A certain large diameter portion will be supported by the pin guide. Further, since the tip of the small diameter portion of the print wire does not protrude from the end surface of the pin guide when not driven, breakage may occur due to the tip of the print wire contacting any obstacle when not driven. Nor.

Therefore, the shortage of the strength of the printing wire, which has been a problem in the related art, can be solved and the breakage of the printing wire can be prevented.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing the structure of the main part of the wire dot print head of this example, in which 1 is a printing wire and 2 is a pin guide.

The printing wire 1 is formed by connecting a small-diameter portion 4 having a diameter of 0.16 to 0.18 mm to a tip of a large-diameter portion 3 having a diameter of φ0.2 mm through a conical connecting portion 5 so as to be smoothly integrated.

The pin guide 2 has a hole 6 and has a large diameter portion 3 of the printing wire 1.
Is supported in this hole 6. The diameter of the hole 6 is larger than the diameter of the large diameter portion 3 by about 0.02 mm.

Although only one print wire 1 is shown in FIG. 1,
Actually, a plurality of print wires are provided in a predetermined arrangement.

At the time of printing, a predetermined printing wire 1 is driven at a predetermined time by a driving mechanism (not shown). As a result, the printing wire 1 advances to the left in FIG. 1 by a predetermined amount, and the tip of the printing wire 1 presses the ribbon against the platen (not shown) through the paper to perform printing. The printing wire 1 that has completed printing returns to the original position even if it retracts.

As described above, since the printing is performed by the small diameter portion at the tip of the wire, it is possible to improve the printing quality by increasing the number of pins.
Moreover, since printing is performed by the small diameter portion 4, the surface pressure at the tip of the wire is increased and the copy capability is improved.

Further, the small-diameter portion 4 at the tip of the printing wire 1 is integrally connected to the large-diameter portion 3 via the conical connection portion 5, so that the large-diameter portion 3 at the breakage point, which has been a problem in the past, is , Will be supported in the hole 6 of the pin guide 2.
Further, since the tip of the small-diameter portion 4 of the printing wire 1 does not project from the end surface of the pin guide 2 when not driven, as shown by the solid line in FIG.
There is no possibility of breakage due to contact of the tip of the with some obstacle.

Therefore, it is possible to prevent the shortage of the strength of the print wire, which has been a problem in the related art, and prevent the breakage of the print wire.

〔The invention's effect〕

As described above, according to the present invention, it is possible to reduce the tip diameter of the printing wire without causing breakage of the wire, and it is possible to improve the printing quality and the copying ability by increasing the number of pins.

[Brief description of drawings]

FIG. 1 is a side view showing a main part structure of a wire dot print head according to an embodiment of the present invention. In the drawing, 1 is a printing wire, 2 is a pin guide, 3 is a large diameter part, 4 is a small diameter part, and 5 is It is a conical connection part.

Claims (1)

[Claims] 1. A wire dot print head comprising a plurality of print wires (1) supported by a pin guide (2) so as to be able to move back and forth, wherein the print wires (1) are attached to the tip of a large diameter portion (3). The small diameter portion (4) is formed by gently connecting it through a conical connection portion (5), and the large diameter portion (3) of the printing wire (1) is supported by the pin guide (2). A wire dot print head, characterized in that the tip of the small diameter portion (4) of the print wire (1) does not protrude from the end face of the pin guide (2) when not driven.