JPH02273245A - Printing head - Google Patents

Abstract

PURPOSE:To eliminate movement of a wire during printing and to improve printing quality by securing the end of the front part of a head frame by clamping an end guide for guiding the wire. CONSTITUTION:An opening 1b is formed at the lower part of the guide hole 1a at the end of the front part of a head frame 1, and a threaded hole 1c is formed at one side face of the opening 1b. The other side face of the opening 1b is formed with a clamping part 1d to be secured to the other side face of the opening 1b by clamping an end guide 3, and a screw 1e is inserted into the hole 1c via a through hole formed at the clamping part 1d, and clamped to narrow the opening 1b to clamp the guide 3 thereto. Thus, since the guide 3 is positioned at the hole 1a of the frame 1 to be secured, it does not move during printing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a print head, and particularly to a print head used in an impact dot matrix printer.

[Conventional technology]

A conventional print head used in an impact dot matrix printer has a configuration as shown in FIG. That is, the protrusion of the tip guide 33 is inserted into the guide hole 34 of the tip guide for guiding the tip of the printing wire (wire) provided at the front tip of the head frame 31, and the guide hole 34 and the tip guide 33, there is a gap d, and the positional relationship between the two is not fixed in a constant state.

[Problem to be solved by the invention]

As mentioned above, in conventional print heads, the protrusion of the tip guide is inserted into the guide hole for the tip guide provided at the front tip of the head frame. The guide hole must be larger than the convex portion of the tip guide, so a gap is created in the vertical and horizontal directions between the guide hole of the head frame and the tip guide. Therefore, during the operation of the print head, the tip guide moves vertically and horizontally by the gap between it and the guide hole in the head frame, and as a result, the wire guide hole formed in the tip guide and the tip Since the wire guided through the wire guide hole of the guide also moves in the vertical and horizontal directions, there is a drawback that printing quality is degraded.

[Means to solve the problem]

The print head of the present invention includes a yoke having a plurality of yoke cores each having a coil wound thereon, an armature provided corresponding to the yoke core and operated by energizing the coil, and a terminal end at the tip of the armature. a plurality of printing wires to which are fixedly attached, a tip guide having a plurality of wire guide holes that pass through the tip of the printing wire and guide the printing operation, and a tip of the tip of the tip guide is inserted into and supported. In a print head including a head frame having a cylindrical leading end, an opening is provided in a part of the leading end of the head frame, and the leading end guide is positioned and fixed by tightening and narrowing the opening with a screw. It was designed to do so.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
FIG. 3 is a front view showing details of the head frame and tip guide of the illustrated embodiment.

In FIG. 1, a plurality of wires 2 that perform reciprocating motion, a tip guide 3 and wire guides 4 and 5 that guide their motion are provided in a head frame 1 whose front portion is cylindrical. There is.

The tip guide 3 is disposed by inserting its convex portion into a guide hole 1a for guiding the tip guide at the tip of the front part of the head frame 1, and the tip guide 3 and the wire guides 4 and 5 are arranged in a straight line. They are lined up and pressed against the head frame 1 by a guide spring 6 and housed therein. A plurality of guide holes 3a, 4a, and 5a are formed in the tip guide 3 and wire guides 4 and 5, respectively, and the wire 2 passes through these guide holes 3a, 4a, and 5a to prevent its movement. Being guided.

The drive unit that drives the reciprocating motion of the plurality of wires 2 includes an armature 8 to which the yoke 7 and the wires 2 are fixed;
It is configured to include a coil 9 that generates magnetic flux. The yoke 7 includes a plurality of yoke cores 7 that hold the coils 9.
a are arranged concentrically, and these yoke cores 7
An armature 8 is provided opposite to a. The armature 8 has one end pressed against the yoke 7 by a hold spring 10 in the form of a leaf spring, and an armature support 11 disposed corresponding to the armature 8.
is positioned by. In addition, a return spring 1 is provided corresponding to the armature support 8.
2 is disposed in a spring holder 13, and the other end of the armature 8 is pushed back in the return direction by the return spring 12 and is held by being pressed against the stopper plate 14. Each yoke core 7a has a coil 9
The two terminal portions of this coil 9 are connected to a substrate 16 attached to the yoke 7 via an insulating member 15, so that they can be energized.

In such a configuration, when the coil 9 is selectively energized, the coil 9 generates a magnetic flux, which causes the armature 8 to move around the end pressed against the yoke 7 by the hold spring 10 and the opposite end thereof. At the same time, the wire 2 fixed to the armature 8 is driven and moved forward to perform predetermined printing. After printing is completed, the power to the coil 9 is cut off, so the armature 8 rotates together with the wire 2 by the return spring 12, and its end is pressed against the stopper plate 14 and held.

As shown in Fig. 2, the relationship between the head frame and the tip guide is that an opening 1b is provided at the bottom of the guide hole 1a at the front tip of the head frame 1, and a screw is provided on one side of the opening 1b. A hole 1c is provided. The other side of the opening 1b has a tightening section 1 for tightening and fixing the tip guide 3.
d, and this tightening is done by inserting and tightening the screw 1e into the screw hole 1c through the through hole provided in the portion 1d, thereby narrowing the opening 1b and tightening and fixing the tip guide 3. In this way, the leading edge guide 3 is positioned and fixed in the guide hole 1a of the head frame 1, so that it does not move during the printing operation.

〔Effect of the invention〕

As explained above, in the print head of the present invention, the front end of the head frame can be fixed by tightening the end guide that guides the wire, so that the wire can be prevented from moving during the printing operation. This has the effect of providing an excellent print head with improved print quality.

FIG. 3 is a front view showing details of the head frame and leading edge guide of the embodiment shown in FIG. 1, and FIG. 3 is a front view showing the head frame and leading edge guide of an example of a conventional print head.

1.31...Head frame, 1a.3a.4a.5
a.34...Guide hole, 1b...Opening, IC...
Screw hole, 1d...Tighten part, 1e...Screw, 2...
・Wire, 3.33... Tip guide, 4.5... Wire guide, 6... Guide spring, 7... Yoke, 7a... Yoke core, 8... Armature, 9
...Coil, 10...Hold spring, 11.
... Armature support, 12... Return spring, 13... Spring holder, 14... Stopper plate, 15... Insulating member, 16... Board.

Claims (1)

[Scope of Claims] A yoke having a plurality of yoke cores each having a coil wound thereon, an armature provided corresponding to the yoke core and operated by energizing the coil, and a distal end portion at the distal end of the armature. A tip guide having a plurality of fixed printing wires, a plurality of wire guide holes passing through the tip of the printing wire and guiding the printing operation, and a cylinder into which the tip of the tip guide is fitted and supported. In a print head comprising a head frame having a shaped leading end, an opening is provided in a part of the leading end of the head frame, and the leading end guide is positioned and fixed by tightening and narrowing the opening with a screw. A print head characterized by: