SU556915A1 - Device for welding insulated wire to metal parts - Google Patents

Description

Invention otioops to the field of equipment for resistance welding.

A device is known for the P1I1 connection of insulated wire to a part, which contains an electrode made of two insulated plastics isolated from each other, between which an insert and a material with high ohmic resistance are placed. A disadvantage of this device is that it does not provide the required quality of the welded joint.

It is also known a device for welding insulated wires to a metal piece, which contains a welding pressure drive associated with an electrode made in the form of js & x current-conducting insulated from each other with bevels on the working ends on the side of the insulating strip to accommodate the welded wire.

However, using this device, you can connect only one wire at a time and only one diameter at a time.

The aim of the invention is to increase labor productivity by providing simultaneous welding of several wires and increasing the range of diameters of the wires to be welded.

In order to achieve this goal, the proposed device is provided with a conductive insert mounted between the beveled ends of the plates and the drive for moving the insert in the direction of the movement of the plates.

FIG. 1 shows an apparatus for welding an insulated wire to a metal part; in fig. 2 is the same; the section along A-A in FIG. one.

The device comprises two conductive plates 1 and 2 for one-sided welding, which are fixed on a common holder 3 made of an insulating material. Thus, the plates are insulated from each other by a gasket 4 and provided with separate current leads 5. At the ends of the plates 1 and 2 facing the gasket 4, the bevels are filled, and between them is placed a driving conductive insert. It is in contact with the ends of the plates and is attached to the ends of the rods 7 and 8, connected by a cross-beam 9, which is affected by the rod 10 of the drive for moving the liner.

In one embodiment (see Fig. 1), the conductive insert 6 is pressed against the plates 1 and 2 by means of springs 11 and 12 and has a prismatic cross section.

Alternatively (see Fig. 3), the biconducting insert 6 has a straight sectional section and is movable in a rectangular recess. The conductive insert 6 provides electrical contact between the ends of the plates 1 and 2. The device is fixed to the stem of a welding machine equipped with a gun, pneumatic or other pressure actuator by means of an adapter 13.

Using such a device, welding of the insulated wire 14 (or several wires simultaneously) to a metal part, mainly to the printed circuit board 15, is carried out.

The device works as follows.

The welded insulated wires 14 overlap the metal part — the contact pad of the printed circuit board 15. In the initial state, the frame formed by the parts 5, 7, 8 and 9 is in the upper position using springs 11 and 12, forming a recess for the wire 14. When In this case, the movable conductor plug 6 having a prismatic cross section is in contact with the ends of plates 1 and 2, shorting them, Element 6 having a rectangular cross section (see fig. 3), constantly shorting the ends of electrodes 1 and 2 facing the wire 14 In this position the device the ends of the plates 1 and 2 are placed on the contact pad of the printed circuit board 15, and the wires to be welded are placed in the recess between the ends of the plates 1 and 2 and the liner 6. The impulse of the current applied to the plates .1 and 2 by the current leads 5 is included. 6 is heated. The metal part 15 is heated by the current passing through it between the ends of the plates 1 and 2. Between the plates and the contact area (copper, trimmed, silver plated) of the part 15, the contact resistance is small and depends on the pressure applied to the plates. This pressure is regulated. Depending on the ratio of the pressure and the width of the working end of the plates, the amount of current flowing through the part 15 will vary, and therefore its heating will also change. The heated part will transfer the heat of the wire insulation 14 and soften it. The movable liner 6 is also heated as it short-circuits the plates 1 and 2. In this case, the transient

The resistance is great and the heat generated by the contact transition resistance will soften the insulation of the wires 14 on the other hand.

The expansion insulation is easily dispensed by the movable liner 6 when a drive force is applied to it by the rod 10 and it acts on the wire 14.

When the prismatic insert 6 is moved down, the plates open and turn into ordinary doubles, between which the current flows through the part - the contact pad - of the printed circuit board 15, heating it. Moving the rectangular insert down decreases the resistance of the lower circuit (plate 1 - contact pad - plate 2) and as a result, the amount of current passing through part 15 increases the concentration of heat at the welding site.

Isolation is either removed from the contact zone, or evaporated (depending on its type).

The bare wire 14 is pressed against the part 15 by a movable liner 6 and under the action of a current and is attached to it by pressing in

into it due to the melting of the surface. Weld wire 14 is not deformed at this.

Claims (1)

Invention Formula Device for welding insulated wire to metal parts, comprising a welding pressure drive associated with an electrode made in the form of two conductive insulated plates from each other with bevels on the working ends on the side of the insulating gasket-. For placement of welded wire, it is intended that, in order to performance by providing simultaneous welding of several wires and increasing the range of diameter of the welding wires, the device is equipped with a conductive plug inserted between the beveled ends of the plates and a drive for moving the specified insert in the direction of the plates moving. I from fpuB.Z Figure 1 drive