JPS63315255A - Printing head - Google Patents

Abstract

PURPOSE:To achieve improvement of yield by correction of dispersion of a kinetic characteristic of a printing head caused by dispersion of each parts, by annexing a connection body prepared by connecting a plurality of coils and a positioning regulation mechanism in a yoke lengthwise direction of the connection body. CONSTITUTION:A plurality of coils corresponding to respective yoke columns are arranged annularly in a head and are, in a united body, connected by resin molded material 15. A screw thread is formed concentrically with a lengthwise center line of a printing head on an exposed outer periphery 15a near a head frame. Then, an annular component 16 of which on an inner periphery a female screw to be bound correspondingly with the screw of the molded material is formed, is in a rotary free manner arranged on an outer side of the head frame. Further, a plate spring 17 is positioned between the molded material and the yoke, which energizes the molded material onto an armature side. By rotating the annular component, a position of the molded material containing a plurality of coils can be optinally regulated along a lengthwise direction of the yoke.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a print head for a dot matrix printer that performs printing by selectively impacting a recording medium with a print wire.

[Conventional technology]

Conventionally, this type of print head has a yoke and a coil forming an electromagnet.

He was dressed in a fixed position.

[Problem that the invention seeks to solve]

The above-mentioned conventional print heads have large variations in dynamic characteristics such as printing force and response speed after assembly due to fluctuation factors such as variations in the dimensional accuracy of individual component parts and variations in materials. Obtaining the desired properties is a challenge, and yields are inevitably poor. In order to reduce the variation in the VC dynamic characteristics (4), it is necessary to suppress the variation in the degree of M1'j of each individual component to a small value 9, which has the drawback of increasing manufacturing costs.

[Means for solving problems]

The print head of the present invention includes a connecting body that connects a plurality of coils, and a positioning adjustment mechanism for the connecting body in the longitudinal direction of the yoke.

〔Example〕

FIG. 1 shows an example of a print head according to an embodiment of the present invention.

The armature 1 holds the print wire 2 at one end, and the other end is supported by a support rubber 4 integrally formed with the stopper plate 3 on the outer peripheral side end surface of the yoke 5, forming a fulcrum. A coil 6 is installed in the columnar part 5c located inside the yoke.
are located, the yoke outer peripheral part 5a, the bottom part 5b, the inner columnar part 5
A magnetic circuit is formed by forming a U-shape with the C and placing the armature on top of it. When a current is applied to the coil, magnetic flux flows within the magnetic circuit and the armature.

A suction force acts on the gap formed between the yokes, and the armature is attracted toward the yoke surface. As the armature moves, the print wire is guided by the intermediate guides 8 and 9 held by the head frame 7 and the main guide 10, and then passed through the ink ribbon 11 and paper 12 to the platen 1.
Printing is performed by colliding with 3. A plurality of coils corresponding to each yoke column are arranged in an annular shape within the head and are integrally connected by a resin molded body 15. The molded body is extended in a circular tube shape inside the annular coil array so that a part thereof protrudes outside the head frame in the longitudinal direction of the yoke, and the longitudinal center line of the print head is located at the outer periphery 15a of the exposed part from the head frame. The screws are formed concentrically.

On the other hand, an annular member 16 is rotatably disposed on the outer surface of the head frame, and has a female thread formed on the inner periphery thereof to be fastened correspondingly to the thread of the molded body. Further, a plate spring 17 is located between the molded body and the yoke, and urges the entire molded body toward the armature side. By rotating the circular portion, the position of the molded body containing a plurality of coils can be arbitrarily adjusted along the longitudinal direction of the yoke. By positioning the coil close to the end face of the yoke column, that is, the magnetic circuit, the magnetic flux flowing through the gap when the coil is driven increases, and the attractive force acting on the armature can be increased.
Moreover, the printing power of the print wire can be increased. Conversely, if the coil is moved away from the yoke end face E, the response speed of the armature can be slowed down and the striking force can be weakened.

〔Effect of the invention〕

As explained above, the present invention adds a mechanism that can simultaneously adjust the position of multiple coils in the longitudinal direction of the yoke of the electromagnet actuator, thereby adjusting the magnetic flux flowing through the gap in the magnetic circuit of the electromagnet and reducing the attractive force acting on the armature. It is possible to correct variations in the dynamic characteristics of the print head caused by variations in the constituent parts that are being adjusted, thereby providing a print head with good yield and low manufacturing cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a print head according to an embodiment of the present invention.ゝ-1ζ − t...armature, 2...printed wire. 3...Stopper rubber, 4...Support rubber, Yoke, 6...Coil, 7
...Head frame, 8.9 ...Middle guide, 10 ... King guide, 11 ... Ink ribbon, 12 ... Paper, 13 ...Platen. 14... Coil spring, 15...
Mold mature 1 piece 3nq-

Claims (2)

[Claims] (1) A print head having a plurality of electromagnetic actuators formed by a yoke, an armature, and a coil, wherein the plurality of coils are connected, and the print head has a mechanism for adjusting the position of the connected body of the coils in the longitudinal direction of the yoke. print head. (2) a connecting body in which the positioning adjustment mechanism is disposed so as to be movable in the longitudinal direction of the yoke; and a spring member disposed between the connecting body and the yoke to bias the connecting body toward the armature;
The print head according to claim 1, comprising a threaded portion fastened correspondingly to the connecting body threaded portion, and an annular member rotatably disposed outside the head.