JP2758863B2 - Print head used for dot impact printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head used for a dot impact printer.

[0002]

2. Description of the Related Art FIG. 5 is a sectional view showing the structure of a conventional print head. Referring to FIG. 5, this conventional print head has a magnetic circuit formed by a yoke 5, a coil 6, and an armature 10. Armature 10
The print wire 7 is brazed to the tip of the armature, and is positioned by the armature support 4. Further, a leaf spring hold spring 11 formed corresponding to the plurality of armatures 10 installed concentrically is provided. The free end on the outer peripheral side of the hold spring 11 presses the armature 10 from a position facing the printing surface 12 so as to press the rotation center 10a of the armature 10. At this time, in the contact portion between the armature 10 and the hold spring 11, the force applied to the armature 10 of the hold spring 11 due to the rotational movement of the armature 10 is directed to the armature rotation center point 10a at any position. Designed for

Next, the printing operation of this conventional print head will be described. From a state in which the armature 10 is pressed against the stopper plate 9 by the return spring 8, the armature 10 is magnetically attracted to the yoke 5 by the magnetic flux generated by the energized coil 6, and the print wire 7 is
Is driven. After energizing coil 6, armature 1
Numeral 0 is pressed against the stopper plate 9 by the return force of the return spring 8, stops, and ends one printing process.

[0004]

Conventionally, in this type of print head, since the armature 10 is pressed by the holding spring 11 of a leaf spring and the point 10a of the armature 10 is set as the center of rotation, the armature 10 is rotated when the armature 10 rotates. Since there is friction at the contact portion between the coil 6 and the hold spring 11, which is an operational resistance, a large amount of energy given by energizing the coil 6 is required. In addition, it is difficult to extend the life because of wear. In addition, since the restraining force of the hold spring 11 on the armature 10 is opposite to the magnetic attraction direction of the armature 10, there is a disadvantage that much energy given by energizing the coil 6 is required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a print head used in a dot impact printer capable of reducing frictional resistance due to contact with other parts of an armature, prolonging the life and reducing energy loss due to the armature rotation center pressing parts.

[0006]

A print head used in a dot impact printer according to the present invention has a magnetic circuit composed of a yoke, a coil and an armature, and drives a print wire by rotating the armature. In a print head used for a dot impact printer that performs printing by hitting a printing surface via an ink ribbon, a first groove concentrically arranged on an outer peripheral portion, extending in a printing surface direction, and a concentric first groove on a printing surface side bottom surface. A disk-shaped stopper plate having a plurality of pillars having a plurality of pillars and being provided at a position facing the printing surface of the armature; and a second groove cut from a surface facing the stopper plate toward its own rotation center. The armature, which is alternately and concentrically arranged with the pillar, and the first plate and the armature when the stopper plate and the armature are assembled. Beauty and a rubber ring annular molded by extendable material that is disposed in the second groove.

[0007]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a structural view showing an embodiment of the present invention, FIG. 2 is a detailed view of a main part of the embodiment, and FIG. 3 (a) shows a relationship between a stopper plate and an armature. 3B is a sectional view taken along the line AA of FIG. 3A, FIG. 4A is a detailed top view of the armature, and FIG. 4B is a detailed side view of the armature.

Referring to FIG. 1, FIG. 2, FIG. 3 and FIG. 4, a print head used in the dot impact printer of this embodiment has a magnetic circuit composed of a yoke 5, a coil 6, and an armature 2. A print head that drives the print wire 7 by rotating the armature 2 and strikes the print surface 12 via the ink ribbon to perform printing.
Groove 1c concentric with the bottom surface on the printing surface 12
Armature 2 having a plurality of pillars 1a and 1b having
And a disc-shaped stopper plate 1 installed at a position facing the printing surface 12 of the first column, and a second groove 2b is cut from a surface facing the stopper plate 1 toward its own rotation center.
armature 2 alternately and concentrically arranged with a and 1b, and a ring-shaped rubber formed of a stretchable material arranged in first and second grooves 1c and 2b when assembling stopper plate 1 and armature 2 And a ring 3.

The print head of this embodiment has a yoke 5,
The armature 2 has a magnetic circuit formed by the coil 6 and the armature 2. The armature 2 has a printing wire 7 attached to the tip thereof, and the armature 2 is positioned by the armature support 4. A plurality of columns 1a and 1b extending in the direction of a plurality of printing surfaces 12 are concentrically arranged on the outer periphery of a disk-shaped stopper plate 1 installed at a position facing the printing surface 12 of the armature 2. The columns 1a and 1b are inserted between the armatures 2 arranged concentrically. Further, the pillars 1a and 1b of the stopper plate 1 have grooves 1c concentric with the outer periphery of the stopper plate 1 on the bottom surface of the pillar on the printing surface 12 side. The groove 1c has a shape in which the center side wall of the print head is inclined and the print surface side becomes wider. Armature 2 is stopper plate 1
A groove 2b is cut from the side surface toward the rotation center point 2a of the armature 2.

Stopper plate 1 and armature 2
Each of the grooves 1c and 2b has a rubber ring 3 formed of a ring-shaped extensible material arranged at the time of assembly. When assembling the print head, the yoke 5, coil 6, armature support 4, armature 2, rubber ring 3, and stopper plate 1 are assembled in this order. On this occasion,
The rubber ring 3 is arranged in the groove 2b of the armature 2,
When the stopper plate 1 is assembled, the stopper plate 1
And is incorporated in the groove 2b of the armature 2 and the groove 1c of the stopper plate 1.

In the printing operation, after the armature 2 is pressed against the stopper plate 1 by the return spring 8 and the coil 6 is energized, the armature 2 is magnetically attracted to the yoke 5 by the magnetic flux generated in the coil 6 and printed. The operation is performed by driving the wire 7, and at this time, the armature 2 performs a rotary motion while being pressed toward the rotation center by the tension of the rubber ring 3. After the energization of the coil 6 is completed, the armature 2 is pressed against the stopper plate 1 by the return spring 8 and stops, thereby completing one process.

[0013]

As described above, according to the present invention,
Since the center of rotation of the armature is changed from a hold spring to a rubber ring, the contact between the armature and the hold spring is eliminated, the friction between the armature and the hold spring is eliminated, and as a result, there is no movement resistance and the coil Energy given by energization can be reduced. Similarly, since the contact portion between the armature and the hold spring is eliminated, the generation of abrasion powder can be suppressed, and the life can be extended. Furthermore, since the restraining force applied to the armature rotation center of the hold spring and opposite to the magnetic attraction direction of the armature has been eliminated, the energy given by energizing the coil can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a detailed view of a main part of the embodiment.

FIG. 3 is a diagram showing a relationship between a stopper plate and an armature. FIG. 3B is a sectional view taken along the line AA of FIG.

FIG. 4 (a) is a detailed top view of an armature,
FIG. 4B is a detailed side view of the armature.

FIG. 5 is a main detailed view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stopper plate 2 Armature 3 Rubber ring 4 Armature support 5 Yoke 6 Coil 7 Print wire 8 Return spring 9 Stopper plate 10 Armature 11 Hold spring 12 Printing surface

Claims (1)

(57) [Claims] 1. A dot impact device having a magnetic circuit composed of a yoke, a coil, and an armature, wherein a printing wire is driven by a rotational movement of the armature, and printing is performed by hitting a printing surface via an ink ribbon. A print head used in a printer, comprising a plurality of columns arranged concentrically on an outer peripheral portion and extending in a print surface direction and having a concentric first groove on a print surface side bottom surface, and a position facing the print surface of the armature. A disc-shaped stopper plate installed on the armature; the armature having a second groove cut from a surface facing the stopper plate toward the center of rotation of the armature and arranged alternately and concentrically with the column; A ring-shaped rubber ring formed of a stretchable material disposed in the first and second grooves when the plate and the armature are assembled; A print head for use in a dot impact printer, comprising: