JPS5968264A - Preparation of printing head of dot printer - Google Patents

Abstract

PURPOSE:To perform the positional determination of a leaf spring member and an operation body with high accuracy, by a method wherein a projection for projection welding is formed to either one of the leaf spring member and the operation member and, after both members are temporarily connected by electric resistance welding, they are soldered in a high temp. furnace. CONSTITUTION:When a current is supplied between a fixed electrode 9 and movable electrode, applied voltage and the supplied current are concentrated to a projection 1a which is, in turn, contacted with an operation body 6 under pressure while a copper film 6a melted by Joule heat generated by current supply is excluded. When a lead spring member 1 and the operation body 6 are temporarily connected and subjected to heat treatment at a temp. capable of melting copper in a high temp. furnace, the copper film 6a plated to the operation body 6 is melted. After the gap 12 formed between the leaf spring member 1 and the operation body 6 is filled with molten copper by a capillary phenomenon, the leaf spring member 1 and the operation body 6 are subjected to copper soldering on cooling.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a method of manufacturing a print head for a dot printer.

Prior Art Conventionally, a print head installed in a dot printer has a base end fixed to a frame, a print wire fixed to an operating end, and an electromagnetic wire attached to one side of a leaf spring member selectively actuated by an electromagnetic solenoid. The actuator is welded to form a magnetic path for the lines of magnetic force generated by the solenoid to reduce magnetic resistance, thereby increasing the response characteristics of the leaf spring member to the drive of the magnetic solenoid and enabling high-speed printing. 1111 As a method of manufacturing a print head by welding an actuating body to a plate spring member, the actuating body, which has been plated with brazing metal in advance, is temporarily fixed to one side of the plate spring member by electric resistance welding. It is generally known that the two parts are brazed together by melting the brazing filler metal in a high 1M furnace. However, it is difficult to reliably temporarily fasten the leaf spring member and the actuating body by electric resistance welding, and the welding cannot be performed with both members positioned with high precision.

In addition, in the method of welding the leaf spring member and the actuating body by arc welding, the structure of the temporary fixing jig for temporarily fixing both members becomes complicated, and a large number of steps are required for temporary fixing, which requires a lot of work. This had the disadvantage of poor efficiency.

OBJECTS OF THE INVENTION In view of the above-mentioned conventional drawbacks, the first object of the present invention is to securely temporarily fasten a leaf spring member and an actuating body by a simple means, and to perform a manual operation while positioning both members with high precision. It is an object of the present invention to provide a method for manufacturing a print head for a dot printer, which enables printing.

Composition of the invention The method of the present invention will be explained below according to examples.

Fig. 1 is a cross-sectional view of the road body showing an outline of a release type print head, and Fig. 2 is a plan view of the road body of leaf spring members. The base ends of the leaf springs 2 are connected to each other, and the operating ends are punched and formed to extend in the centripetal direction.The base ends are clamped and fixed to the rear frame 3a, and the rear side A magnetic body 5 is fixed at a position one distance away from an electromagnetic device 4, which will be described later. Incidentally, the leaf spring 2 at the base end of the leaf spring member 1 is formed with a mounting hole 2a for positioning a rear frame 3a and a pin 10 implanted in a fixed electrode 9, which will be described later.

The electromagnetic devices 4 are fixed at positions corresponding to the 011 magnetic bodies 5 on the inner peripheral fi11 edge of the rear frame 3a,
Each plate spring member 1 is selectively activated.

The actuating body 6 is welded to the front face of the tip end of each leaf spring member 1, and is designed to reduce magnetic resistance generated from the electromagnetic device 4 (2) by forming a 6-wire magnetic path. The body 5 and the leaf spring member 1 constitute an armature.This armature is held in contact with the core of the electromagnetic device 4 when the electromagnetic device 4 is not driven by a permanent magnet 13 held between the rear frame 3a. There is.

The printing wire 7 is fixed to the operating end of each leaf spring member 1 and the tip of the operating body 6 by brazing, and when the electromagnetic device 4 is driven, it is released from the restraint by the permanent magnet 13 and prints mI. The distal end of the plate spring member l is projected outward from the kite hole 8a of the guide part 8 attached to the part 1111 of the frame 3b by J, and characters, etc. are printed in dots.

FIG. 3 is an explanatory diagram showing an outline of the method for manufacturing a print head according to the present invention. FIG. An appropriate number of projection welding protrusions 1a are integrally formed on the front surface at the same time as the punching and forming the actuating body 6.
A copper film 6a having excellent conductivity is pre-plated as a brazing material to an appropriate thickness on the surface.

A jig 1 for mounting the leaf spring member 1 on a bottle 10 implanted on the fixed electrode 9 with the protrusion 1a facing upward and for positioning the actuating body 6.
After positioning the actuating body 6 on the protrusion 1a'', the movable electrode 11 is brought into pressure contact with the actuating body 6, and the actuating body 6 is pressurized against the protrusion 1a. When electricity is applied between the electrodes 11, the pressing force and current are concentrated at the tip of the protrusion 1a, and the protrusion 1a is pressed against the actuating body 6 while removing the copper film 6a melted by Joule heat generated by the energization. The electrical resistance between the protrusion 1a and the actuating body 6 increases rapidly due to the pressure welding, and the heat generated by the resistance melts and joins the protrusion 1a and the pressure contact surface of the actuating body 6, thereby connecting the leaf spring member 1 and the actuating body 6. Temporarily fasten.

Then, when the temporarily attached leaf spring member 1 and the actuating body 6 are heat-treated in a high-temperature furnace at a temperature sufficient to melt copper, the copper film 6a plated on the actuating body 6 is melted.
The molten copper fills the gap 12 formed between the leaf spring member 1 and the actuating body 6 shown in FIG. 6. Create and braze.

Therefore, in the method of this embodiment, when temporarily fixing the leaf spring member 1 and the actuating body 6 by electric resistance welding, the pressure (J) and the current applied are concentrated on the protrusion 1a, so that the leaf spring member 1 and the actuating body 6 are It is possible to obtain a welded print head with secure temporary fixing and high positional accuracy.

In addition, in the method of this embodiment, the plate spring member 1 on which the protrusion 1a is formed and the actuating body 6 on which the brazing material ii and the film 6a are plated are temporarily attached by electric resistance welding. Naturally, the method of the invention can also be carried out by temporarily fixing a plate spring member plated with a brazing material and an actuation body having a protrusion by electric resistance welding.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, an actuating member is welded to one side of a leaf spring member whose proximal end is fixed to a frame, and a printing wire is fixed to the actuating member or the working end of the leaf spring member. )I
In the method for manufacturing a print head in which the actuating member is selectively actuated by an electromagnetic device to drive a printing wire, one of the plate spring member and the actuating member is plated with a brazing material, and one of both members is plated with a brazing material. The leaf spring member and the actuating body are assembled by forming projection welding protrusions on the plate, temporarily fixing both members by electric resistance welding, placing the members in a high-temperature furnace, and brazing both members with the brazing metal. To 11! This is a method for manufacturing a print head for a dot printer, in which both members can be temporarily attached and then brazed with both members positioned with high precision.

[Brief explanation of the drawing]

Fig. 1 is an analysis view of a road body 1 schematically showing a release type print head, Fig. 2 is a plan view of a leaf spring member, and Fig. 3 is an explanatory diagram showing an outline of a method for manufacturing a print head according to the present invention. , ′,i! Figure 4 is an enlarged sectional view of the road body in a temporarily fixed state, in which 1 is a leaf spring member, 1a is a protrusion, 3a is a rear frame, 4 is an electromagnetic device, 6 is an operating member, and 6a is a brazing material. 7 is a printing wire. Patent applicant Brother Industries, Ltd. Agent Patent attorney Ip Fuji Ken - Figure 1

Claims (1)

[Claims] 1. An actuating member is welded to one side of the leaf spring member whose base end is fixed to the frame, a printing wire is fixed to the actuating member or the actuating end of the leaf spring member, and the actuating member electromagnetic device selectively In the method for manufacturing a print head in which the printing wire is driven by actuation, one of the n11 plate spring member and the actuation member is plated with a brazing material, a protrusion for projection welding is formed on one of both members, and both 1. A method for manufacturing a print head for a dot printer, characterized in that after the members are temporarily fixed by electric resistance welding, the members are placed in a high temperature furnace and both members are brazed with the brazing filler metal.