JPS6310229Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a welding head used for welding a lead wire to an electrical component such as a resistor. This invention relates to a device that improves the responsiveness of chuck operation, reduces the weight of the head itself, improves the follow-up performance of the head during welding, and, as a result, improves welding performance.

A resistor is made by attaching a resistance material such as carbon to the surface of a cylindrical element, fitting metal caps to both ends of the element to adjust the resistance value, and then attaching a lead wire to the cap. The manufacturing process involves welding.

By the way, in the lead wire welding process mentioned above,
Conventionally, as shown in FIG.
A cap a is held in contact with the electrode, and a lead wire d is held by a chuck mechanism e that also serves as another electrode of the welding machine.
A method is adopted in which a relatively large current is passed between the pair of electrodes while pressing the tip of the cap against the cap a. In this way, the part of the pair of electrodes with the highest resistance, that is, the contact part between the cap a and the lead wire d, generates heat, and this heat slightly melts the tip of the lead wire d, which is then transferred to the cap a. It is welded.

The chuck e is built into a welding head f which is movable in the axial direction of the element body b to be held by the holding part c. This welding head f first assumes a retreated position and clamps the tip of the lead wire d led out from a lead wire supply section (not shown), and then moves the tip of the clamped lead wire d so that it comes into contact with the cap a. In this state, the lead wire d and the cap a are welded together by applying current between the electrodes, and the lead wire d is cut to a predetermined length, and then the lead wire d is moved back again.
Repeat the above operation while holding the tip of the Also,
In order to improve the finish of the welding between the lead wire d and the cap a and to shorten the welding time of the head f, as shown in FIG. It is necessary to bias the cap a to be welded with appropriate elasticity using a spring h or the like. In other words, the lead wire d when energized
If the lead wire d is not pushed in by an amount corresponding to the length of the melt, a so-called explosion phenomenon will occur, and the molten lead wire will fly away due to the electric energy.
This is because not only the welding is not completed completely, but also the spattered molten metal stains the equipment around the welding head f, especially the chuck mechanism, etc., and this extremely deteriorates the welding performance.

However, in the conventional welding head f, as shown in FIG. 1, the chuck mechanism e for clamping the lead wire d is operated by an air cylinder g built into the head f. As a result, the weight of the welding head f itself becomes considerably large, and even if it is elastically biased as described above, the welding head f cannot move sufficiently to follow the instantaneous melting speed of the lead wire d. Therefore, there is a limit to increasing welding efficiency by shortening the time required for one welding operation. In addition, a device and a hose for generating compressed air to be sent to the air cylinder g are required, making the entire device large-scale, causing many failures, and increasing costs.

The present invention was devised in view of the above-mentioned circumstances, and its purpose is to sufficiently follow the elastic biasing force of a spring or the like to drive the lead wire by the length of the melted lead wire. The first objective is to reduce the inertial weight of the welding head and simplify the structure of the welding head, thereby reducing costs, reducing failure rates, and improving welding performance.

In order to achieve such an objective, the present invention takes the following technical measures.

That is, one end of a double wire formed by passing an inner wire through a cylindrical outer wire is connected to reciprocating motion imparting means outside the welding head, and the other end is connected to a chuck mechanism inside the welding head. By driving the reciprocating motion imparting means,
The chuck mechanism can be operated.

Thus, the lead wire welding head of the present invention is
Since the air cylinder for the chuck mechanism that was built into the conventional welding head is removed, the weight of the welding head itself is considerably reduced compared to the conventional welding head, which allows it to fully follow the melting of the lead wire during welding. You will be able to move around. As a result, even if the time required for one welding operation is considerably shortened, the explosion phenomenon does not occur, and the efficiency of the equipment can be dramatically improved. There is no need for a generator, etc., and the configuration of the entire welding device can be greatly simplified.

Embodiments of the present invention will be specifically described below with reference to the drawings.

Reference numeral 1 indicates a holding member that holds a resistor 4 with caps 3 fitted into both ends of the element body 2, and this also serves as one electrode of a welding device using the so-called resistance welding method. There is. In addition, this holding member 1 has, for example, a plurality of holding grooves formed on the circumferential surface of a cylindrical intermittent rotating drum so that a plurality of resistors 4 can be continuously fed to a predetermined welding position. It is convenient to configure as follows. 5 is
A welding head is shown which, together with the lead wire cutting unit 6, is movable linearly in the wire direction of the lead wire, ie in the axial direction of the resistor 4. In the illustrated example, the welding head 5 and the lead wire cutting unit 6 move the cylindrical sliding rings 7 and 8 attached thereto onto a guide bar G disposed parallel to the axis of the resistor 4. By fitting the resistor 4 in a slidable manner, the resistor 4 can be moved in the axial direction. Further, a spiral groove-shaped feed cam 9 is formed on the outer periphery of the guide bar G, and a protrusion 9a formed on the inner periphery of the sliding ring 7 of the lead wire cutting unit 6 engages with this feed cam 9. are doing. Therefore, when the guide bar G is rotated in the forward or reverse direction, the lead wire cutting unit 6 and the welding head 5 are moved in the direction of arrow F or R in FIG. 2.

A lead wire chuck mechanism 11 capable of clamping the tip of the lead wire 10 is built into the welding head 5. This chuck mechanism 11 includes a fixed chuck 12 positioned such that its chuck portion 12a contacts the appropriate front portion of the lead wire 10, and a chuck portion that faces the chuck portion 12a of the fixed chuck 12 with the lead wire 10 in between. 14a,
Also, an opening/closing chuck 14 that can rotate around a fixed fulcrum 13, a pressure lever 15 for pressurizing this opening/closing chuck 14, and this pressure lever 15.
It consists of a double wire W connected to the The pressurizing lever 15 has its tip pressing portion 16 abutting against the back of the opening/closing chuck 14, preferably at an intermediate portion close to the chuck portion 14a, and rotates around a fixed fulcrum 17 close to the pressing portion 16. It's getting wet. Note that the fixed chuck 12
Alternatively, the opening/closing chuck 14 also serves as an electrode of the welding device. Furthermore, one end of the inner wire wa of the double wire W is fixed to the rear end of the pressure lever 15. Further, the end of the outer wire wb of this double wire W is fixed to an appropriate part of the case 18 of the welding head 5. Further, the other end of this double wire is used to fix the end of the outer wire wb to a fixing member and to take up the end of the inner wire wa with a winding device (not shown).
It is connected to an appropriate reciprocating motion imparting means (not shown) by fixing it to, etc., or the like.

In the lead wire chuck mechanism 11, when the reciprocating motion imparting means imparts reciprocating motion in the axial direction to the inner wire wa and outer wire wb of the double wire W, that is, for example, the second
In the figure, when the inner wire wa is pulled in the direction of the arrow p, the opening/closing chuck 14 cooperates with the fixed chuck 12 and rotates in a direction to clamp the lead wire 10, and on the other hand,
When the pulling force of this inner wire wa is relaxed and it is let out in the direction of arrow Q, the opening/closing chuck 14 rotates in the opposite direction to the above and releases the lead wire 10.

As is clear from the figure, a coil spring 19 is interposed between the welding head 5 and the lead wire cutting unit 6. This is because during welding, the welding head 5 is always elastically biased in the direction of arrow F in FIG. be. Furthermore, a cutting mechanism 20 is installed inside the lead wire cutting unit 6 for cutting the lead wire 10 to a certain length after welding.

The operation of the above configuration is as follows.

At a position retreated in the direction of arrow R from the position in FIG. 2, the chuck mechanism 11 of the welding head 5 is
holds the lead wire 10. Then guide bar G
rotates, and the lead wire cutting unit 6 and welding head 5 move in the direction of arrow F. The lead wire cutting unit 6 and welding head 5 are moved to a position where the tip of the lead wire 10 abuts against the cap 3 of the resistor 4 on the holding member 1 with appropriate pressure,
A large current is then passed between the two electrodes, and at this time the tip of the lead wire 10 and the cap 3 are welded. The tip of the lead wire 10 is melted by the heat, and the elasticity of the spring 19 interposed between the welding head 5 and the lead wire cutting unit 6 slightly follows the welding head 5 in the direction of arrow F. Since the amount will be compensated immediately, there is no need to worry about a blowout phenomenon occurring. In particular, in the welding head 5 of the present invention, the chuck mechanism 11 does not use an air cylinder as in the past, but is extremely simple in that the chuck is operated by a double wire W connected to an external reciprocating motion imparting means. Moreover, since a lightweight structure is adopted, the inertial weight of the welding head 5 is dramatically reduced compared to the conventional welding head, and this welding head 5 is capable of instantaneously melting the tip of the lead wire during welding. You can follow and move.

When the welding is completed, the cutting mechanism 20 in the lead wire cutting unit 6 is activated to cut the lead wire 10 at a predetermined length from the welded portion. Next, welding head 5 and lead wire cutting unit 6
moves in the direction of arrow R and returns to its original position, and again holds the vicinity of the tip of the lead wire 10 and repeats the same operation as above. Note that at this time, the holding member 1
, the next resistor 4 is positioned at a predetermined welding position.

As explained above, the lead wire welding head of the present invention has a simple and lightweight structure in which the driving force of an external drive source is connected to the chuck using double wires as its chuck mechanism. The inertial resistance is reduced, and the molten lead wire can be pushed in extremely smoothly and reliably. As a result, it is possible to significantly speed up the welding process for lead wires of resistors, etc., which leads to a reduction in manufacturing costs of electrical components.

It goes without saying that the scope of the present invention is not limited to the embodiments shown in the drawings.

That is, in the embodiment, the pressure lever is interposed between the double wire and the opening/closing chuck, but the pressure lever may be omitted and the opening/closing chuck and the double wire may be directly connected. Further, in the embodiment, a clamping pressure is applied to the opening/closing chuck by imparting relative movement to the double wire, but on the contrary, for example, a tensile force is applied between the fixed chuck and the opening/closing chuck. A force for clamping the lead wire may be constantly applied to the chuck by interposing a spring, and the clamping force of the chuck may be released by applying relative movement to the double wire. Further, as a method for imparting relative movement to the inner wire and outer wire that constitute the double wire, in addition to pulling the inner wire, it is also possible to push the outer wire. Further, as the inner wire, in addition to using a pull-type inner wire made of thin wires tied together, a push-pull type made of a single rigid wire can also be used.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional example, and FIG. 2 is a partially sectional plan view showing an embodiment of the present invention. 5...Welding head, 10...Lead wire, 11...
...chuck mechanism, W...double wire, wa...
Inner wire, wb...outer wire.

Claims (1)

[Scope of utility model registration request] A welding head that is used in welding equipment for welding lead wires to electrical parts, etc., and has a chuck mechanism for holding the lead wire inside.It is a welding head that is used for welding lead wires to electrical parts, etc., and has a chuck mechanism for holding the lead wire inside. One end of the double wire inserted therein is connected to an external reciprocating motion imparting means, the other end is connected to the chuck mechanism, and the chuck mechanism is operated by driving the reciprocating motion imparting means. A welding head characterized by: