JPS61222759A - Dot printer head - Google Patents

Abstract

PURPOSE:To permit high-speed printing to be performed by providing an electromagnet by which to restore a mobile iron piece to the original position and then stop it, separately from an electromagnet to drive the mobile iron piece. CONSTITUTION:When a mobile iron piece 7 with a projected needle 8 is restored by the force of a spring 10 by displacement, stop current is supplied to the coil 15 of an electromagnet 13 for stopping. The piece 7 is attracted by the magnet 13 and then by a core 14. Therefore, the bounding of the piece 7 by collision with the electromagnet 13 is avoided. Since the time until it is stopped is short, the drive current can be quickly supplied, and the printing speed can thus be hastened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a dot printer head that forms dots on a recording medium by driving a printing element such as a needle, and prints characters, figures, etc. with a collection of these dots. It is something.

Conventional technology Conventionally, in printers that use a needle as a printing element, there is an impact method in which the needle collides with the recording paper to form a dot, and an impact method in which the needle is held in the tip of the needle and brought close to the recording paper to remain static. There is a non-impact type that uses electric or electromagnetic force to propel the ink. In either system, the needle returned to its original position after being driven is stopped by a stopper or damper. An example of this conventional dot printer head will be explained based on FIG.

First, a driving electromagnet 4 consisting of a core 2 and a coil 3 is provided within the housing 1 . This driving electromagnet 4
A fulcrum 6 is formed at the end of the yoke 5 which is integral with the core 2. A portion of the core 2 is joined to this fulcrum 6.
A movable iron piece 7 facing the is rotatably provided, and a needle 8 as a printing element is attached to the tip of the movable iron piece 7. The needle 8 has its tip protruding from the nose 9 of the housing 1. Further, the movable iron piece 7 is urged in a direction away from the core 2 by a compression spring 1o. The back of this movable iron piece 7 is damper 1
1, and its original position at rest is determined. Further, the back surface of the movable iron piece 7 on the fulcrum 6 side is prevented from lifting up by a pressing spring 12.

Thus, the coil 3 of the drive electromagnet 4 is energized with a drive current A that matches the print signal, and when this current is energized, the movable iron piece 7 is attracted to the core 2, causing the needle 8 to protrude. As a result, the needle 8 either collides with the recording paper or comes close to it, forming a dot depending on the printing method. and,
After protruding, the needle 8 and the movable iron piece 7 return to their original positions due to the force of the compression spring 10, but they collide with the damper 11 and are stopped at their original positions.

Problems to be Solved by the Invention As shown in FIG.
However, at the time of return, the return speed is high, so the impact colliding with the damper 11 is large, and as a reaction, the repulsive force is also large, so it bounces against the pressing force of the compression spring 10.

This bouncing is repeated multiple times, and it gradually decays and comes to rest. Therefore, the next drive current A cannot be applied until the movable iron piece 7 has completely stopped, making it impossible to perform high-speed printing.

Means for Solving the Problems Separate from the driving electromagnet for driving the movable iron piece, a stopping electromagnet is provided for returning the movable iron piece to its original position before operation and stopping it.

By energizing the stopping electromagnet when the working movable iron piece returns, the movable iron piece is attracted by the attractive force of the stopping electromagnet and stops without bouncing. Therefore, the time required for the printer to come to rest is short, and the next drive current can be applied quickly, resulting in high-speed printing.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 and 2. Components that are the same as those described in connection with FIG. 3 above are designated by the same reference numerals, and explanations thereof will be omitted.

In this embodiment, a stopping electromagnet 13 is provided at the position where the damper 11 described above was provided.

This stopping electromagnet 13 consists of a core 14 and a coil 15.

In such a configuration, a drive current A is applied to the drive electromagnet 4.
When energized, the movable iron piece 7 is attracted by the drive electromagnet 4 and displaced, causing the needle 8 to protrude, similar to that shown in FIG. 3 above. The movable iron piece 7 thus displaced is returned to its original position by the force of the compression spring 10, but at the time of this return, a stopping current B is applied to the coil 15 of the stopping electromagnet 13. The magnetic flux generated by this stop current B attracts the movable iron piece 7 and causes the movable iron piece 7 to be attracted to the core 14. Therefore,
The movable iron piece 7 does not collide with the stopping electromagnet 13 and bounce. It is desirable that the energization timing of the stop current B to perform such an operation is such that the energization is started when the movable iron piece 7 is close to the core 14 of the stop electromagnet 13. As a result, the magnetic flux of the stop electromagnet 13 is reduced. Movable iron piece 7
This reduces the acceleration of the return speed of the core 14, and effectively prevents the occurrence of bouncing after colliding with or approaching the core 14.

Although the operation of the movable iron piece 7 is performed repeatedly in this manner, the time from when the movable iron piece 7 is started until it comes to a complete standstill is shortened, and the interval at which the drive current A is applied can be shortened. Therefore, high-speed printing becomes possible.

Effects of the Invention The present invention includes, in addition to the driving electromagnet that drives the movable iron piece as described above, a stopping electromagnet that returns the movable iron piece to its original position before operation and stops it.

By attracting the movable iron piece, this stopping electromagnet can reliably prevent the movable iron piece from bouncing, which occurs when the movable iron piece returns.This shortens the time from when the movable iron piece starts to when it comes to a complete standstill. This enables high-speed printing.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional side view showing one embodiment of the present invention, Fig. 2 (
a) (b) (c) are waveform diagrams showing the timing of the drive current, stop current, and displacement of the movable iron piece, Fig. 3 is a longitudinal cross-sectional side view showing an example of the conventional example, and Fig. 4 (a) and (b) are FIG. 3 is a waveform diagram showing the timing of the drive current and the movable iron piece. 4...Driving electromagnet, 7...Movable iron piece, 8...Needle (printing element), 13...Stopping electromagnet Application
People Tokyo Electric Co., Ltd. 3” Country, 732 Tsuyoshi

Claims (1)

[Claims] A driving electromagnet for driving a movable iron piece holding a printing element is provided, and the printing element is moved toward a recording medium by applying a driving current that matches a printing signal to the driving electromagnet, A dot printer head characterized in that a stop electromagnet is provided for returning the movable iron piece to its original position before operation and stopping the movable iron piece.