SU546449A1 - Device for welding isolated wire - Google Patents

Description

one

The invention relates to equipment for welding a thin insulated irovka to a metal part in radio electronics and instrument making.

A device for welding insulated wires is known, which contains the lower and upper electrodes and a contact electrode, the lower edge of which lies in the same plane with the upper electrode and touches its side surface 1.

A disadvantage of the known device is the unreliability of fixation of the welded irrovolka.

Also known is a device for welding insulated wire containing two electrodes fixed in a holder insulated from one another, whose working ends are made with bevels that form a recess of a prismatic shape to accommodate the wire to be welded, and are installed with the possibility of contact between themselves and the specified prismatic recess 2

However, this device is not universal enough; it cannot be used to connect wires of different diameters. If it is necessary to connect wires of other diameters, it is required to have an appropriate number of devices, which reduces the efficiency of the device.

In order to expand the range of diameter of the welded wires by adjusting the distance between the working ends of the electrodes facing the wire, with the preservation of electrical contact between them, the proposed device for connecting the insulated wire provided with epo with two sliders with adjustable stops and attached to the electrode transducer, which is located at the apex of the prismatic recess, while the crawlers are fitted with the possibility of displacement in the specified radius and leveling elements x and sharirio electrodes are fixed on the optics with the ability to interact with adjustable stops

FIG. 1 shows schematically an image of a device for welding insulated wire; in fig. 2 - meleda notch ends

0 electrodes and wire placed in it; in fig. 3 - a variant of the use of the device.

The device contains electrodes 1 and 2 for one-sided welding, which are mounted on sliders 3 and 4, made of insulating material. Electrodes 1 and 2 are provided with separate current leads 5 and 6. The working ends of electrodes 1 and 2 form a recess of a prismatic shape to accommodate the curved wire 7 and are interconnected

0 in electrical contact made by

the top of the prismatic notch. The sliders 3 and 4 are mounted with the possibility of mixing along the radius guides 8, the axis 9 of which coincides with the linpea of contacting the electrodes 1 and 2 mounted on the sliders 3 and 4 with the help of hinges 10 and 11 and interacting with the adjustable stops 12 installed on the sleeves, providing a reliable electrical contact between the ends of the electrodes 1 and 2, which face the wire 7 and are rounded to ensure constant contact between the ends of these electrodes while adjusting the size of the recess.

The sliders 3 and 4 are moved along the guides 8 by means of a screw 13 with right and left threads. Correspondingly, nuts 14 and 15 are made to the right and left threads, interacting with the screw 13, which move along the guide 16 and are connected with the sliders 3 and 4. The screw 13 adjusts the position of the sliders 3 and 4 on the guide 8 and, accordingly, the size of the notch between the ends of electrodes 1 and 2. After adjusting, the slide blocks 3 and 4 are fixed with screws 17 and 18. The position of electrodes 1 and 2 is recorded on a scale of 19. With the help of the 2U shank, the device can be attached to the compression rod of the micro-welding machine. Using such a device, it is possible to connect the wire 7 both insulated and non-insulated to the contact pad 21 of the printed circuit board 22.

The device works as follows.

The copper wire 7 insulated with a layer of varnish is superimposed on the lead pad 21 of the printed circuit board 22 coated with tin alloy. The electrodes 1 and 2 are superimposed on the wire 7 so that it appears in the notch between the ends of the electrodes that touch the contact pad 21. The size of the notch can be adjusted with a screw 13 in accordance with the diameter of the wire to be attached 7 (for diameters from 0.05 to 0.25 mm).

When the electric current is switched on, it passes through the line of contact between electrodes 1 and 2, heating up the coic electrode, forming a notch. The heating isolates (squeezes out or evaporates) the insulation of the central part of the wire 7, which is in the recess, and the bare surface of the wire 7 is pressed into the heated contact area 21, which is not deformed, because it is in the recess, serving as a mold for the molten substance of the contact pad 21.

In addition, the device can be insulated (Fig. 3) to connect the insulated wire 7, provided that the electrodes 1 and 2 are rotated 90 ° relative to the axis of the wire 7 (Fig. 2), while the ends of the electrodes 1 and 2 are superimposed on the insulated wire 7 so that the axis of the wire is not parallel to the contact line of electrodes 1 and 2.

Initially, the electric current passing between the electrodes heats the ends of the electrodes 1 and 2, mounted on the wire 7, breaking the insulation both under the electrodes and between the wire 7 and the contact pad 21 of the printed circuit board 22. After breaking the insulation, the electric current between the electrodes 1 and 2 passes not only at the point of their contact 8, but also shunts through the wire 7 and the contact pad 21 (shown by arrows in FIG. 3). As a result, the insulated wire 7 is securely attached to the contact pad 21, the overheating of which and the possibility of peeling from the board 22 is much less.

Claims (2)

1. The patent of Germany No. 1690647, cl. 49 11/16, 1972 equivalent. 2. The patent of France No. 2177836, cl. In 23K 11/20, 1973 (prototype). ig.2 /five U // 9U //// 7U7 //// // L 5