JPS6277140A - Cutter for cutting metallic thin rod having high melting point - Google Patents

Abstract

PURPOSE:To improve the cutting accuracy and the cutting efficiency by using a Co-WC super alloy whose hardness, deflective strength and tensile strength are above specified values, and which contains Co of a prescribed quantity. CONSTITUTION:A material to be cut is cut by shearing force by sliding relatively two pieces of die-shaped cutters having through-holes 25, 26 for passing through the material to be cut. As for the cutter, a super alloy of Co-WC compound containing <=15% Co is used. A mechanical quality of the super alloy is constituted so that >=87 hardness (RA), >=240kg/mm<2> deflective strength, and >=1,130kg/mm<2> tensile strength can be obtained, respectively. In such a way, the cutting accuracy and the cutting efficiency are improved, and also the quality of the cutting surface is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field to Which the Invention Pertains) The present invention relates to a cutter for cutting thin high melting point metal rods 2, such as tungsten wires or molybdenum wires with a diameter of about 1.0 mm or less.

(Prior Art) Conventionally, 1. of metal materials having a high melting point such as tungsten or molybdenum have been used. For example, the following method is used to cut a wire as thin as an Orm to a certain length.

After several dozen wire rods are inserted into the tube 32, the tube 32 is heated and firmly tightened to form a wire bundle 33.

This wire bundle 33 is connected to two positioning stones as shown in FIG.
The material is positioned by a rotary cutter wheel 34 and fed out in constant lengths, and cut into a constant length by a rotary cutting wheel 36 while the refrigerant is applied to the cut portion from a coolant injection nozzle 35.

The wire bundle 33 cut to a certain length in this way is heated, the resin tube 32 binding the wires 2 is melted, and the wires 2 are separated one by one.

The wire rod 2 cut in this way has cut burrs on its end face, so after cutting, burrs are removed using a two-rotation barrel, followed by washing and drying.

(Problems with the Prior Art) When cutting using the conventional cutting method, it is necessary to bundle several dozen wire rods into a bundle in advance, which requires a lot of man-hours.

Cutting burrs or minute cracks often occur on the end face during cutting, and a barrel processing step is required to remove these burrs or cracks.

It is difficult to completely remove microcracks or cracks even with a no-no-rel finish, and bends occur due to intertwining of wire rods during barrel processing.

For this reason, problems such as the necessity of 100% inspection to ensure the quality of the wire material, such as the presence or absence of microcracks and dimensional accuracy, were inevitable.

(Objective of the Invention) An object of the present invention is to provide a cutting cutter capable of cutting high melting point metal thin rods one by one with high dimensional accuracy without producing micro-cracks or cracks.

(Means for Solving the Problems) This invention applies shear force to the material 2 by relatively sliding two die-shaped cutters having through holes 25 and 26 that penetrate the material 2. In the cutters 23 and 24, the material of the cutters 23 and 24 is 15% Co or less.
, o-wc, is made of a cemented carbide material whose mechanical properties are hardness (RA) of 87 or higher, transverse rupture strength (k17/mm") of 240 or higher, and tensile strength (kgAIan2) of 1130 or higher. .

(Example) The present invention will be explained below based on two examples.

FIG. 1 shows the entire cutting machine using the cutter of the present invention.

In FIG. 1, reference numeral 1 denotes a spool holder, and a spool 3 on which a wire 2 such as tungsten wire or molybdenum wire has been wound in advance is placed on the spool holder.

The wire rod 2 wound on the spool 3 is unwound.

The material is supplied via the material completion sensor 4 to the fixed length wire feeding device 2.

The wire rod constant length feeding device includes a slide cylinder 6, a guide roller 7, and a clamp confirmation sensor 8. Clamp cylinder9. It is composed of a stopper or block 10 and a slide stroke adjustment screw 11.

This wire rod fixed length feeding device 5 clamps the wire rod 2 supplied from the spool 3 with a clamp cylinder 9 and uses a slide stroke adjustment screw 1 with a slide cylinder 6.
The set length adjusted by step 1 is accurately supplied to a cutting section 12, which will be described later.

Note that the idle roller 7 mentioned above is for preventing the wire rod 2 from wobbling.

Reference numeral 13 denotes an abnormality confirmation sensor provided at the rear stage of the fixed length wire feeding device 1, which detects whether or not there is an abnormality in the wire 2 supplied to the cutting section 12.

Reference numeral 14 denotes a clamp cylinder provided at the front stage of the cutting section, which is used to fix the wire 2 supplied to the cutting section during cutting, and a clamp confirmation photosensor 15 detects whether or not it has been clamped. It has become.

Two opposing cutters, which will be described in detail, are built into the cutting section, and a thermocouple 16 is provided for detecting the temperature of the cutters and controlling the temperature.

Reference numeral 17 is an A'-eve guide for accurately feeding the wire rod 2 to the cutting section D, and reference numeral 18 is a product storage box for storing the cut wire rod 2.

Reference numeral 19 denotes a cutting cylinder device, which operates a cutter holder head 21 by means of a piston rod 20 that moves up and down toward the cutting section 12.
The wire rod 2 is cut by striking a movable cutter, which will be described later, to slide.

22 and 22' are upper and lower limit switches that control the movement stroke of the piston rod 420.

FIGS. 2a and 2c show the operating state of the cutter of the cutter section 12. FIG.

The cutter part has holes 25 and 26 through which the wire 2 is passed. It is composed of two cutters 23 and 24 facing each other, and as shown in FIG. As shown in FIG. 2, after cutting, the movable force vine 24 automatically returns to its original position, discharges the cut wire (rod), and reloads the wire 2.
It is designed to supply and cut.

FIG. 3 is a perspective view showing how the movable cutter 24 is attached. In the figure, the movable cutter 24 is attached to a cutter holder 27.
A cutter head 21 is provided on the upper surface of this cutter holder 27 and passes through a fixed frame 28 and comes into contact with the piston rod 20, and on the lower surface, a block 29 for pushing up the canter holder is supported via a compression spring 30. Supported.

Therefore, the movable cutter 24 actuates the cutting cylinder 19,
When the cutter head 21 is hit (pressed) by the piston rod 20, the compression spring 3 is applied via the cutter holder 27.
0 is compressed and the wire 2 is slid against a fixed cutter 23 (not shown), which operates as shown in FIG. Original story.

The above configuration is similar to a cutting machine separately proposed by the present applicant, but the present invention is characterized by the following points.

It is generally known that tungsten or molybdenum materials are hard and difficult to cut among high melting point metal rods, but dies, which have been commonly used as cutter materials, are used to cut these materials. 1 steel (SKI, SK2)
When used, cutter life, dimensional accuracy of cut bar material2
The quality of the cut surface, such as cracks, was not fully satisfactory.

The present invention is a cutter for cutting thin rods of high-melting point metal such as tungsten wire or molybdenum wire. Considering the conditions, among the hardening alloys whose composition is CO-WC, Co-WC with 15% or less of Co has mechanical properties such as hardness (RA) of 87 or more and transverse rupture strength (kg/w-2).
) is 240 or more, tensile strength (k1i!/1lI2) is 1
We found that cemented carbide with a grade of 130 or higher was optimal, and we also made cuffs using materials with this material and mechanical properties. There is.

Table 1 shows comparative cutting examples between the cutter of the present invention and cutters other than the present invention.
The inner diameter D1 of the through hole 25 of the fixed cutter 23 is 1.15 m.
m, the length L of the cylindrical part is 0.6 ma, the inner diameter D2 of the through hole 26 of the movable cutter 24 is 1.35 m, the length of the cylindrical part □ is 0.6 ma, A-F shown in Table 3
The tungsten wire with a diameter of 1.0 mm was cut with an accuracy of 10 m ± 0.05, and the cutter was held at a temperature of 400 °C during cutting, and at 3 different cutting speeds. As a body.

In the following, Table 2 also shows that the inner diameter D□ of the through hole 25 of the fixed cutter 23 is 0.35 m, and the length Ll of the cylindrical portion is 0.35 m.
21 The inner diameter D2 of the through hole 26 of the movable cutter 24 is 0.43mm, the length Ll of the cylindrical part is 0.21mm, and the diameter of the tungsten wire to be cut is 0.3fi.
It was cut under the same conditions as the table.

Note that the SKI carbide cutter with a casing in Table 3 F is one in which powder-molded carbide is press-formed into a casing molded by SKI by shrink fitting.

As is clear from the comparative cutting examples in Tables 1 and 2, the dimensional accuracy of the C, D, and E carbide cutters is higher than that of the die steel A and H cutters and the SKI cased carbide cutters F. ,
Both cracks and cracks on the cutting surface are superior, but even with the same carbide cutter, 15% Co-WC of D, which corresponds to the present invention, or 7 of E, compared to 20% Co-WC of C. %
It can be seen that the C'o-WC cutter is superior.

(Effects of the Invention) According to the present invention, thin rods of high-melting point metals such as tungsten wires or molybdenum wires with a diameter of about 1.0 trrm or less can be efficiently cut with good dimensional accuracy and without causing cracks or micro-cracks. As a result, it is possible to obtain high quality and high precision high melting point metal thin rods.

Unlike conventional cutting methods, there is no need for pre-processing such as bundling before cutting, or post-processing such as deburring and inspection after cutting, so that cutting efficiency can be improved.

[Brief explanation of drawings]

FIG. 1 is an overall view showing an example of a shear cutting machine using the cutter of the present invention, and FIG. 2 is a view showing the operating state of the cutter section.
FIG. 3 is a perspective view showing the installed state of the movable cutter of the present invention;
FIG. 4 is a detailed view of the cutter of the present invention, FIG. 5 is a schematic view of a wire bundle used for conventional cutting, and FIG. 6 is a schematic view showing a conventional cutting method. 2: Material to be cut (wire rod), 23, 24: Cutter. 25.26: Through hole.

Claims (1)

[Claims] 1) In a cutter that cuts the material by shearing force by sliding two die-shaped cutters having a through hole that penetrates the material relative to each other, the cutter is made of a Co-based material with a material of 15% Co or less. WC, its mechanical properties have a hardness (RA) of 87
As described above, the cutter for cutting thin rods of high melting point metal is characterized in that it is made of a cemented carbide material having a transverse rupture strength (kg/mm^2) of 240 or more and a tensile strength (kg/mm^2) of 1130 or more.