JPS6355378B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal wire cutting device, and more specifically, the present invention relates to a metal wire cutting device, and more specifically, for example, a metal wire cutting device for cutting metal wires to be used as lead wires of glass-sealed diodes, resistors, etc.
The present invention relates to a cutting device that is used when manufacturing a long metal wire by cutting it into a certain length, and is capable of extremely minimizing bending deformation of the cut metal wire during cutting.

In the manufacturing process of glass sealed diodes,
For example, the process of welding a dumet wire and a lead wire with their respective top surfaces facing each other and sealing them with a cylindrical glass with a semiconductor element sandwiched between them is as shown in FIG. is being carried out. That is, the two dumet wires b and c are held with their top surfaces facing each other using a suitable jig a, and are fitted into a cylindrical glass d with some allowance in the inner diameter, and then , by pressing the lead wire e welded to one of the two dumet wires b in the axial direction with a pressing tool g having a holding part f capable of holding the end of the lead wire, the dumet is The contact pressure between the top surfaces of wires b and c and the semiconductor element is maintained at an appropriate level, and the glass d is pressed and heated to tightly adhere it to the outer surfaces of the two dumet wires b and c. I'm letting you do it. The figure shows the glass sealing process for one glass-sealed diode, but in reality, there are many similar to the one shown in the figure lined up in an orderly manner, and it is now possible to glass-seal a large number of diodes at once. There is.

By the way, in the above glass sealing process,
Assuming that the lead wire e welded to the dumet wire b is bent and deformed as shown by the imaginary line in FIG. It becomes impossible to hold line e well. In this case, since the contact pressure between the semiconductor element and the dumet wire does not reach a predetermined value, the glass-sealed diode cannot obtain the predetermined characteristics and becomes a defective product.

The lead wire e described above is manufactured by cutting a long metal wire into a predetermined length. FIG. 2 schematically shows a metal wire cutting device commonly used in such cases. The configuration and operation of this metal wire cutting device are as follows.

The metal wire 1 is pulled out for a predetermined length from the right side in FIG. 2, and is clamped and fixed between two clamps: a first clamp 2 at the front in the wire drawing direction and a second clamp 3 at the rear in the wire drawing direction. A cutting blade device 8 consisting of a fixed blade 5 having a wire holding surface 4 and a movable blade 7 having a wedge-shaped cutting edge 6 is arranged at an intermediate position between these two clamps. By applying the cutting edge 6 of the moving blade 7 to the other side while holding the metal wire 1 on the holding surface 4,
A shearing force is applied to the wire rod on the left side of the cutting blade device 8 to separate it from the wire rod on the right side. After cutting, the first clamp 2 and the second clamp 3 release their clamping forces to drop the cut metal wire 1a, and then pull out the metal wire 1 by a predetermined amount again to repeat the same operation as described above.

In the conventional metal wire cutting device 8 as described above, the metal wire 1 to be cut during its cutting action is
There was an inconvenience that the material was bent and deformed. That is, as shown in FIG. 3, when the movable blade 7 cuts into the metal wire 1, the slope 6a of the cutting edge 6 applies a bending moment to the metal wire in the direction of the arrow p in FIG. Such deformation of the metal wire 1 remains as plastic deformation even after cutting. This is thought to be because the portion A of the metal wire 1 that is pushed away by the slope 6a of the cutting edge 6 is instantaneously compressed and deformed. Such a phenomenon becomes particularly noticeable when the cutting edge 6 deteriorates as shown in FIG.

The above phenomenon can be prevented to some extent by reducing the inclination angle of the wedge of the movable blade 7, but this will cause another problem of extremely shortening the life of the blade edge, so this should not be adopted carelessly. I can't.

When the above-mentioned glass-sealed diode lead wires are manufactured using such conventional metal wire cutting equipment, many of the lead wires are bent and deformed as described above, and therefore the lead wires that have passed through the glass sealing process are mixed in. It is clear that the yield of subsequent products will be poor.

The present invention was devised in view of the above circumstances, and an object of the present invention is to provide a metal wire cutting device that can extremely reduce residual bending deformation of cut metal wires.

In order to achieve this objective, the metal wire cutting device of the present invention takes the following technical measures. That is, the metal wire is sequentially fed out by a wire feeding device, and two clamping mechanisms are provided at the front in the feeding direction to clamp the metal wire at two clamping points, and a pair of cutting blades is provided between the two clamping mechanisms. In a metal wire cutting device equipped with a cutting blade device that shears the wire through engagement, each of the two clamping mechanisms comprises a clamp that clamps and fixes or releases the metal wire, and the two clamping mechanisms are arranged on the front side in the wire feeding direction. a clamp biasing mechanism that supports the clamp movably in the wire feeding direction and biases the clamp in the wire feeding direction; and a biasing force release mechanism that releases the biasing force applied to the clamp by the clamp biasing mechanism. and by synchronizing the operations of the two clamping mechanisms, the clamp biasing mechanism, the biasing force release mechanism, and the cutting blade device, the biasing force release mechanism is actuated to move the clamp to the front side. After the metal wire is clamped between the two clamps with the biasing force released, the operation of the biasing force release mechanism is stopped, and the front side clamp is moved in the wire rod feeding direction by the clamp biasing force mechanism. The cutting blade device is energized to perform cutting in this state.

In the above configuration, when cutting the wire, first, the urging force release mechanism is activated to release the urging force on the front side clamp, and after the metal wire extracting device is clamped and held by each clamp, The state in which the biasing force on the clamp is released is switched to the biased state by the clamp biasing mechanism, the front side clamp is biased in the wire feeding direction, and the wire is sheared in this state. Therefore, during cutting, the metal wire held by the clamp receives a tensile force forward in the wire feeding direction via the front clamp. As a result, when the cutting blade cuts through the metal wire, tensile stress is applied to the entire cross section of the metal wire in front of the cutting blade device, so the cutting blade quickly bites into the wire.
In other words, stress concentrates on the part cut by the cutting blade, which helps the shearing action of the cutting blade and reduces cutting resistance, reducing unnecessary bending force acting on the wire. Even if a bending force is applied due to biting, tensile stress acts on the wire in the axial direction to alleviate the force, and the synergistic effect of these forces makes it possible to shear the wire without causing bending deformation.

As described above, the cutting device according to the present invention synchronizes the operations of the two clamping mechanisms, the clamp biasing mechanism, the biasing force release mechanism, and the cutting blade device, that is, operates them at the appropriate timing, thereby cutting the wire rod. Holding and clamp biasing can be performed in conjunction with each other, and after the wire is clamped and held, a tensile force is applied to the front of the wire to shear it, making it possible to obtain straight cut materials without causing bending deformation. This has the effect that the cutting resistance by the cutting blade device can be reduced and the life of the cutting blade device can be extended.

Hereinafter, the outline of the cutting action by the cutting device according to the present invention will be explained with reference to FIGS. 5 and 6. Fifth
A metal wire feeding device (not shown) is provided on the right side of the figure for sequentially feeding metal wires in predetermined lengths in the direction of arrow F. The metal wire 11 fed out by a predetermined amount is fixed by two clamps, a first clamp 12 located at the front in the direction in which the wire is fed, and a second clamp 13 located at the rear. A cutting blade device 18 consisting of a fixed blade 15 having a wire holding portion 14 and a movable blade 17 having a wedge-shaped cutting edge 16 is disposed between the first clamp 12 and the second clamp 13. Further, the front clamp of the pair of front and rear clamps 12 and 13, that is, the first clamp 1
2 is biased forward in the wire rod feeding direction, that is, in the direction of arrow F by a spring 19. Clamp 1
2 and 13 are adapted to reciprocate as shown by arrows in the figure to clamp and release the metal wire 11. In the illustrated example, a compression coil spring 19 is interposed between a support means 20 for reciprocatingly supporting the first clamp 12 and a suitable fixing member 21.
The clamp 12 is biased in the direction of arrow F. Although the spring hooking mechanism using the coil spring 19 is not shown, it does not always bias the first clamp 12, but has a biasing function after clamp chucking.

In the device of the present invention, as shown in FIG.
When the movable blade 17 cuts into the metal wire 11,
This metal wire is pulled forward by the first clamp 12, so that the cut portion is cut into the movable blade 1.
Even if a bending moment in the direction of arrow m is applied to this portion when it is pushed open by the slope 17a of No. 7, it will not undergo bending deformation even elastically as shown in FIG. Therefore, even after cutting, no bending deformation remains and a straight metal wire can be obtained.

A preferred embodiment of the invention will be described with reference to FIGS. 7 and 8. In this embodiment, a cutting device according to the present invention is applied to process equipment for welding a sheared wire to a dumet wire, and a metal wire 11 is used.
After cutting the metal wire to a predetermined length, the process of welding the cut metal wire to the dumet wire b is performed at the same time.

The long metal wire 11 wound into a roll is straightened into a straight line by a feed roller 22 and sent to a predetermined length cutting position. In the direction in which the metal wire is fed, from the right in FIG. 7, there are a second clamp 13,
A cutting blade device 18, a first clamp 12, and a dumet wire welding device 23 are arranged.

The second clamp 13 is configured such that two members facing each other sandwiching the metal wire move in the direction of the arrow to clamp or release the metal wire. The cutting blade device 18 has a central through hole 24.
A fixed blade 15 that holds a metal wire 11 therein and has a vertical flat surface 25 on the front surface, and a wedge-shaped cutting edge 16 that reciprocates in the vertical direction so as to graze the vertical flat surface of the fixed blade 15. The movable blade 17 has a movable blade 17. The first clamp 12 has a top surface 28 of an arm-shaped main body 27 whose one end is rotatably supported by a fixed member 26.
and a clamping surface 30 formed on a sliding member 29 that is supported so as to be able to slide a certain distance relative to this main body 27.
A metal wire 11 is appropriately sandwiched between the two. The sliding member 29 is always urged by a spring 32 so that its clamping surface 30 approaches the top surface 28 of the main body 27, and in order to release the clamp, the sliding member 29 is forced by a cam 31. This is done by moving in the direction opposite to the biasing direction by the spring 32. This first clamp 12
Also, by interposing a spring 19 between it and the fixed member 33, it is always urged to rotate in the feeding direction (forward direction) of the metal wire, that is, in the direction of arrow f in FIG. . However, the cam 34 allows this urging force to be released. In addition, in the figure, the reference numeral 35 indicates the first
A stopper for defining the rotation end of the clamp 12 is shown. In the dumet wire welding device 23, the dumet wires b before welding are sequentially fed to predetermined positions. Note that the first clamp 1
A spring 19 is installed between the main body 27 and the member 33 in order to bias the main body 27 of the second wire rod in a direction to swing it forward.
The spring hooking mechanism to which the cam 34 is attached corresponds to the clamp biasing mechanism of the present invention, and the cam mechanism consisting of the cam 34 brought into contact with the main body 27 is adapted to the elastic force of the spring 19 depending on the rotational position of the cam 34. Against this, the main body 27
It rotates in the opposite direction to the biasing direction, and corresponds to the biasing force release mechanism of the present invention.

The operation of the metal wire cutting device of this embodiment is as follows.

Before the first clamp 12 clamps the metal wire 11, it is rotated in the direction of the arrow r by the cam 34, and the biasing force of the spring 19 is released. When the metal wire 11 is fed a predetermined length, the first and second clamps 12 and 13 are activated to fix it. The cam 34 then rotates as shown by the imaginary line, causing the first clamp 12 to move in the direction indicated by the arrow f.
An elastic rotational force in the direction is applied. Therefore, at this time, a tensile force is acting on the metal wire between the first clamp 12 and the second clamp 13. In this state, the cutting blade device 18 operates to cut the metal wire 11 along the vertical flat surface 25 of the fixed blade 15. Even in this case, as explained above, it goes without saying that no bending deformation remains in the cut metal wire. When the metal wire is cut, the first clamp 12 is rotated by the tensile force of the spring 32 until it comes into contact with the stopper 35, that is, until it comes into contact with the stopper 35, as shown by the imaginary line in the figure.
At this time, the front end 11b of the metal wire 11, which is still held by the first clamp 12, is brought into contact with the center of the top surface of the dumet wire b, which is supported coaxially with the metal wire 11a in the dumet wire welding device 23. At the same time, they are welded correspondingly. That is, the dumet wire support section 36 of the welding device and the clamp section 30 of the first clamp 12 also serve as electrodes for so-called projection welding. When this welding is completed, the first clamp 12
Then, the second clamp 13 is released, and the same operation as above is repeated thereafter.

It goes without saying that the scope of the present invention is not limited to the above embodiments. In this explanation,
As an example of a metal wire that requires linearity of shape,
Although lead wires for electronic components such as glass-sealed diodes have been mentioned and suitable for manufacturing such lead wires as an example of the apparatus of the present invention, the present invention is not limited to this. It can be adapted as a device for cutting all kinds of metal wires where strength is required.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the glass sealing process of a glass seal diode, Fig. 2 is a schematic configuration diagram of a conventional metal wire cutting device, and Figs. 3 and 4 are explanations of the operation of a conventional metal wire cutting device. 5 and 6 are explanatory diagrams of the cutting action of the cutting device according to the present invention, FIG. 7 is a diagram schematically illustrating the configuration of an embodiment of the present invention, and FIG. - It is a line arrow diagram. 11... Metal wire, 12... First clamp, 1
3... Second clamp, 18... Cutting blade device, 19
……Spring.

Claims (1)

[Scope of Claims] 1. A metal wire is sequentially fed out by a wire feeding device, and two clamping mechanisms are provided at the front in the feeding direction to clamp the metal wire at two clamping points, and between the two clamping mechanisms In a metal wire cutting device, which is equipped with a cutting blade device that shears the wire by engaging a pair of cutting blades, each of the two clamping mechanisms consists of a clamp that clamps and fixes or releases the metal wire, and one of the clamps includes a wire feeding mechanism. A clamp biasing mechanism that supports a clamp disposed on the front side of the direction so as to be movable in the wire rod feeding direction and further biases the clamp in the wire rod feeding direction, and a clamp biasing mechanism that releases the biasing force applied to the clamp by the clamp biasing mechanism. By synchronizing the operations of the two clamping mechanisms, the clamp biasing mechanism, the biasing force releasing mechanism, and the cutting blade device, the biasing force releasing mechanism is actuated to release the biasing force. After the metal wire is clamped between the two clamps with the biasing force applied to the clamp on the wire feeding direction side being released, the operation of the biasing force release mechanism is stopped, and the clamp is moved by the clamp biasing mechanism. biasing the wire rod in the feeding direction;
A metal wire cutting device, wherein cutting is performed by the cutting blade device in this state.