JPH0438591B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact dot head for an impact dot printer that selectively drives wires to form dot matrix characters.

Conventionally, in this type of impact dot head, as shown in FIG. When the actuator 22 and the fulcrum presser spring 25 are operated, wear occurs on both sides due to spillage between the actuator 22 and the fulcrum presser spring 25, and an appropriate fulcrum presser force cannot be obtained, making the operation of the actuator 22 unstable. There was a drawback that sufficient printing energy was not transmitted to wires (not shown), resulting in deterioration of printing quality.

Further, in the case of the actuator 32 of the type shown in FIG. 6, since the actuator 32 becomes a part of the magnetic path of the drive coil 33, it is necessary to use a soft magnetic material. However, since the soft magnetic material has low hardness, the wear of the actuator 32 at the engaging portion A becomes extremely large, resulting in a disadvantage that printing quality deteriorates as described above.

In the impact dot head constructed as described above, there was a major problem in that the operation of the actuator became unstable due to wear and the printing quality deteriorated.

The present invention eliminates the above-mentioned drawbacks, and its purpose is to prevent wear of the engagement portion between the fulcrum presser spring and the actuator, maintain operational stability of the actuator, and provide good printing quality. The objective is to provide an impact dot head that can be maintained.

The impact dot head according to the present invention includes a plate-shaped actuator whose rear end portion is bent in a substantially dogleg shape toward the opposite side of the drive unit and serves as a rotational fulcrum, and It has a pressing part that presses the rear end side from the fulcrum part. and a wear-resistant lubricating member disposed between the two.

Hereinafter, the present invention will be explained in detail based on examples.

In FIG. 1, the actuator 2 has its rotational fulcrum portion rotatably guided by the projection 4a of the coil bobbin 4, and the fulcrum presser spring 5 applies a pressing force to the rotational fulcrum of the actuator 2 in the direction of the arrow. giving. Here, the engagement portion between the fulcrum presser spring 5 and the actuator 2 is as shown in the enlarged view of FIG. A lubricating member 6 is provided between them. As the lubricating member, a fibrous sheet impregnated with oil or a self-lubricating Teflon sheet is suitable.

A plunger 13 is fixed to the actuator 2, and forms a suction portion together with a core 9 provided in a part of the yoke 8. One end of the actuator 2 engages with the wire 1, and the wire 1 is slidably guided by a wire guide 12. The wire return spring 11 connects the wire 1 and actuator 2 to the stopper 10.
It is pressed and positioned in the standby state.

When the drive coil 3 is energized for an appropriate period of time, a magnetic flux is generated as shown by the dotted line in FIG. Print dots on a paper surface not shown.

At this time, sliding movement occurs at the engagement portion between the actuator 2 and the fulcrum presser spring 5, but in the present invention, the engagement portion between the fulcrum presser spring 5 and the actuator 2 has an R shape. In addition, since the lubricating member 6 is interposed, the sliding friction load is reduced and the wear resistance of this part is improved, and the pressing force by the fulcrum presser spring 5 does not change, so the stability of the actuator 2 is maintained and good performance is achieved. Print is obtained.

FIGS. 3 and 4 show other embodiments of the present invention, in which the R-shaped portion of the fulcrum presser spring 5 or the engaging portion of the actuator 2 with the fulcrum presser spring 5 is made of a material having lubricating properties, e.g. This is an example of Teflon coating.

In FIG. 3, a Teflon coating layer 16 is provided on the R-shaped portion of the fulcrum presser spring 5, and the actuator 2 is attached via the coating layer 16.
, the wear resistance is improved as in the previous embodiment.

In FIG. 4, the actuator 2 has a Teflon coating layer 26, and is engaged with the R-shaped portion of the fulcrum presser spring 5 through the coating layer 26, so that the effect of improving wear resistance is achieved. be.

In addition to Teflon coating, molybdenum disulfide coating or the like may be used.

As detailed above, the present invention has the following remarkable effects.

That is, the pressing part of the fulcrum presser spring presses the rear end side of the rotation fulcrum part of the actuator, and a rotational moment acts on the actuator in the direction of returning the wire, so a member for returning the wire is used. This reduces the load on the (wire return spring) and contributes to simplifying the wire drive mechanism and improving printing speed. Furthermore, when pressing the actuator inward from the rotational fulcrum, a force in the direction of the wire (inward) acts on the actuator and attempts to move the actuator inward, but in this application,
Since the pressing portion of the fulcrum presser spring presses the rear end side of the actuator bent in the direction of the fulcrum presser spring, it is also possible to prevent the generation of such a component force.

Furthermore, a wear-resistant lubricating member is placed between the actuator and the pressing part of the fulcrum presser spring, which is bent into a dogleg shape. Occurrence is prevented,
It is possible to realize a long-life impact dot head that guarantees stable actuator operation over a long period of time.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an impact dot head showing one embodiment of the present invention, Fig. 2 is an enlarged view of its fulcrum, Figs. 3 and 4 are enlarged views of the fulcrum of another embodiment, and Fig. 5. , FIG. 6 shows a conventional example. 1... Wire, 2... Actuator, 3
... Drive coil, 5 ... Fulcrum presser spring, 6 ... Lubrication member.

Claims (1)

[Claims] 1. A drive unit consisting of a drive coil, etc.
In an impact dot head that prints by rotating an actuator disposed on the drive unit and driving a wire located at the tip of the actuator, the vicinity of the rear end is on the opposite side of the drive unit. A plate-shaped actuator is bent into a dogleg shape and serves as a rotational fulcrum, and a pressing portion presses a rear end side of the actuator from the rotational fulcrum. A plate-shaped fulcrum presser spring bent into a substantially dogleg shape is provided on the opposite side of the actuator, and a wear-resistant lubricating member disposed between the pressing portion and the actuator. Impact dot head featuring.