JPH02160430A - Method and device for manufacturing metallic fiber - Google Patents

Abstract

PURPOSE:To improve productivity of metallic fiber by vibrating a vibrating bite with an ultrasonic exciter to cut a workpiece, and flattening projected parts after cutting with a stationary bite, at manufacturing metallic fiber using as raw material for various composite materials. CONSTITUTION:A vibrating bite 4 and a stationary bite 5 are arranged so as to contact with a cutting face 1a of a metal block 1 rotating in the arrow mark (a) direction. The bites 4, 5 are fitted to a common base plate 7 moving in the arrow mark (b) direction through respective fixed plates 6. Further, the bites 4, 5 are placed at same angle theta to the center line X of the metal block 1, and difference of position of both bites are set r/cos theta. The vibrating bite 4 performs vibration cutting due to ultrasonic wave from an exciter, and the stationary bite 5 flattens the cutting face 1a by cutting projected parts after cutting with the vibrating bite 4. Thus, by combination of the bites 4, 5, short fiber of constant size can be always produced during one rotation of the metal block 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method and apparatus for producing short metal fibers.

(Prior art) Short metal fibers have various superior properties compared to non-metallic fibers such as glass and carbon, so they are used as raw materials for friction materials and various composite materials such as mortar, plastics, and rubber products. It is expected to have a wide range of uses, including as a raw material for fiber metallurgy, including porous sintered crystals.

By the way, short metal fibers used for such purposes must have an extremely small diameter of 100 μm or less, a short fiber length, and have good physical properties such as tensile strength.

FIG. 5 shows an example of a method for manufacturing such short metal fibers, in which the metal block 1 is rotated in the direction of the arrow y while the cutting tool 2 is placed on the cutting surface 1a at a predetermined position. Notch! , and at the same time generate chatter vibration (self-excited vibration) F while applying a minute feed S to this,
This chatter vibration forcibly cuts the short fibers 3 at the fiber length from the metal block 1.

According to this method, as shown in FIG.
It was possible to directly produce the material from the cut surface 1a of the material, and by using chatter vibration, it was possible to easily produce products with an extremely small diameter of about 20 μm.

(Problem to be solved by the invention) However, in such a conventional method for producing short metal fibers,
Since chatter vibration is used to obtain an excitation force when the cutting tool 2 comes into contact with the cutting surface 1a of the metal block 1, the resonance frequency is limited to a range of 100 to 5 depending on the rigidity of the cutting tool 2.

Therefore, the production ff1H per piece of bite 2 is as follows: the length of the short fiber 3 is 10 ma+, and the thickness of the short fiber 3 is 50 μm.
.

When the resonant frequency of the cutting tool 2 is 5KHz and the material of the metal block 1 is copper (8.93g/am"), H-π/
4 x (0, o5 /10) 2X5000X 8.
93 x3 [ioo”3156g /Ilr: 3
．． 16Kg/)Ir, and it cannot be said that productivity is high at this level.

The present invention has been made under these circumstances.1. It is an object of the present invention to provide a method and apparatus for producing short metal fibers that can improve the productivity of short metal fibers and make the short metal fibers uniform.

[Structure of the Invention] (Means for Solving the Problems) The method for producing short metal fibers according to the first invention of the present application includes rotating a metal block while contacting a cutting tool to vibrate the cutting tool to generate fiber shafts. In the method for producing short fibers whose direction is parallel to the cutting edge of a cutting tool, vibration of the cutting tool is applied by an ultrasonic vibrator, and the apparatus for producing short metal fibers according to the second invention of the present application is A metal block gripping means for gripping the block, a pair of cutting tools for cutting by contacting the surface of the metal block to be cut, an excitation means for applying ultrasonic vibration to one of these cutting tools, and a pair of metal block and a pair of cutting tools for applying ultrasonic vibration to one of the cutting tools. and a rotation drive means for relatively rotating the metal block and the pair of cutting tools so that cutting is performed at their abutting surfaces.

(Function) In the method for producing short metal fibers of the present invention, the surface of the metal block to be cut is cut while applying ultrasonic vibrations to the cutting tool using an ultrasonic vibrator, and the conventional chatter vibration (
It is a cutting tool that does not obtain excitation force by the tool bit coming into contact with the surface to be cut of a metal block like self-excited vibration), but rather obtains excitation force by ultrasonic vibration, which is a periodic external force. The vibration frequency is not limited by the rigidity of the

Further, in the short metal fiber manufacturing apparatus of the present invention, the metal block or the pair of cutting tools that receive driving force from the rotational drive means rotate relative to each other, and when the metal block and the pair of cutting tools approach each other by the moving means, First, these contact surfaces are cut by one of the cutting tools to which ultrasonic vibrations are applied by the vibration excitation means. Thereafter, the protrusions left on the cut surface after cutting are cut and smoothed by the other cutting tool. This produces short metal fibers with uniform thickness.

(Example) Hereinafter, details of an example of the present invention will be described based on the drawings. Note that parts common to FIGS. 5 and 6 are designated by the same reference numerals, and redundant explanations will be omitted.

FIG. 1 shows an embodiment of the apparatus for producing short metal fibers of the present invention.

As shown in the figure, rotational force is obtained by a drive motor through a gear box (not shown) in the direction of arrow a.
A vibrating cutting tool 4 and a stationary cutting tool 5 are arranged so as to come into contact with the cutting surface 1a of the metal block 1 which rotates at a rotation angle of tn>.

In addition, the vibrating tool 4 and the stationary tool 5 are moved in the direction of the arrow through the fixed plate 6 by V-2rN/Cosθ (ms/
It is attached to a common base plate 7 that moves at a +in).

Further, the angle between the vibrating tool 4 and the stationary tool 5 with the center line X of the metal block 1 is the same angle θ, and the positional difference between the vibration tool 4 and the stationary tool 5 is r/cos θ.
It is said that The vibration cutting tool 4 performs vibration cutting using ultrasonic waves with a total amplitude of 2r (1III) from an exciter (not shown), and the stationary tool 5 corresponds to the total amplitude of 2r (mm) after cutting by the vibration tool 4. The convex portions described later are cut to make the cut surface 1a flat.

The short fibers are produced in the following manner.

First, the metal block 1 is fixed with a chuck or the like and rotated at N (rpm) in the direction of arrow a. Next, as shown in FIG. 2, a minute vibration f is applied to the vibrating tool 4 by ultrasonic waves with a total amplitude of 2r (mm), and the short fibers 3 are removed from the cutting surface 1a.
, 3... are forcibly cut. At this time, in the figure, the width C indicates the total amplitude of the vibrating tool 4, and the width d indicates the hand amplitude (
The average machining allowance) is shown, and the vibration tool 4
The direction of the vibration f due to the ultrasonic waves applied to the cutting direction is perpendicular to the cutting direction or at an angle close to it.

In addition, simply add a total amplitude of 2r (lIII) to the vibration tool 4.
When the ultrasonic vibration f of
portion 8a smaller than each convex portion 8 corresponding to rl).

8a... are cut, so the thickness of each short fiber 3a here becomes thinner than that of each short fiber 3 cut by the vibrating cutting tool 4 previously.

Therefore, as shown in FIG. 4, each convex portion 8 having a width C corresponding to the total amplitude 2r(a+) after cutting by the vibrating cutting tool 4 is cut by the stationary cutting tool 5, and the cut surface 1a thereof is made flat.

At this time, each short fiber 3b has a total amplitude 2r of the vibration cutting tool 4.
Since the width C corresponding to (a+a+) is cut, the same thickness as the short fiber 3 by the vibrating cutting tool 4 is cut.

After the cutting surface 1a is flattened by the stationary cutting tool 5, the flat cutting surface 1a is cut again by the vibrating cutting tool 4.

The combination of the vibrating cutting tool 4 and the stationary cutting tool 5 allows short fibers 3 or 3b of a constant thickness to be produced during one rotation of the metal block 1.

In this way, in this embodiment, the vibration cutting tool 4 has a total amplitude of 2r (
A minute vibration f by ultrasonic waves of mm) is applied to the cutting surface 1a.
Each short fiber 3 or 3b is forcibly cut from the metal block 1, and the excitation force F is obtained when the cutting tool 2 comes into contact with the cutting surface 1a of the metal block 1, as in conventional chatter vibration (self-excited vibration). Since the excitation force is obtained by ultrasonic vibration, which is a periodic external force rather than a physical object, the vibration frequency is not limited by the rigidity of the vibrating tool 4. That is, for example, if the frequency of vibration applied to the vibrating tool 4 by ultrasonic waves with a total amplitude of 2r (IIlal) is 20kHz, this is the maximum of the resonant frequency range of the conventional manufacturing method of short metal fibers using chatter vibration. 5. Productivity can be improved four times compared to soil. Furthermore, by cutting each convex portion 8 with a width C corresponding to the total amplitude 2r (lIIIl) using the stationary cutting tool 5, short fibers 3b having the same thickness as the short fibers 3 by the vibrating cutting tool 4 are cut. 2 when the frequency of vibration to the vibration tool 4 is set to 20 k H2.
It is possible to produce short fibers 3 or 3b for 40 kHz, which is double the frequency.

In addition, in this embodiment, the rotation speed N (rpw) of the metal block 1 in the direction of the arrow a, the total amplitude 2r (+a+g) of the ultrasonic wave applied to the vibrating tool 4, and the speed v of the common base plate 7 moving in the direction of the arrow = 2r N/cosθ(is/1n),
Position difference r/cos θ between the vibrating tool 4 and the stationary tool 5
It goes without saying that each of these can be arbitrarily set according to the length, thickness, etc. of the short fibers 3 or 3b.

Further, in this embodiment, the case where the metal block 1 is columnar has been explained, but this is not limited to this example. A coil material obtained by rolling a thin metal plate may be used as the metal block. In this case, the length of the thin plate is Short fibers can be produced efficiently.

[Effects of the Invention] As explained above, according to the method for producing short metal fibers of the present invention, unlike conventional chatter vibration (self-excited vibration), the cutting tool is in contact with the surface of the metal block to be cut. Since the excitation force is not obtained through ultrasonic vibration, which is a periodic external force, the vibration frequency is not limited by the rigidity of the cutting tool, so the vibration of the cutting tool due to ultrasonic waves is By increasing the number, productivity of short metal fibers can be improved. Further, according to the apparatus for manufacturing short metal fibers of the present invention, these contact surfaces are first cut by one of the cutting tools to which ultrasonic vibrations are applied by the vibration excitation means, and after this, the contact surfaces are The convex portion formed by one cutting tool is cut and flattened by the other cutting tool, thereby making it possible to manufacture short metal fibers of uniform thickness.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the apparatus for producing short metal fibers of the present invention, FIG. 2 is an enlarged side view showing the state of cutting by the vibrating tool shown in FIG. 1, and FIG. 3 is the same as shown in FIG. 1. Vibration f due to ultrasonic waves with a total amplitude of 2r (IIffi) is simply applied to the vibration bite of
Fig. 4 is an enlarged side view showing the cutting state when using a static cutting tool in Fig. 1, and Fig. 5 is an enlarged side view showing the cutting state when using a static cutting tool in Fig. 1. FIG. 6 is a perspective view showing an example of the manufacturing method, and FIG. 6 is an enlarged side view showing the state of cutting by the cutting tool of FIG. DESCRIPTION OF SYMBOLS 1... Metal block, 1a... Cutting surface, 3, 3 short fibers, 4... Vibrating tool, 5... Stationary tool, fixed plate, 7... Common base plate. Applicant Showa Cable and Wire Co., Ltd. Agent Patent Attorney Sa Suyama - (1 other person) b... 6... -111111 Rabeko

Claims (2)

[Claims] (1) In a method of manufacturing short fibers in which the fiber axis direction is parallel to the cutting edge of the cutting tool by abutting a cutting tool while rotating a metal block and vibrating the cutting tool, the vibration of the cutting tool is generated by ultrasonic waves. 1. A method for producing short metal fibers, characterized in that the metal fibers are given using a vibrator. (2) a metal block gripping means for gripping a metal block; a pair of cutting tools for cutting by contacting the surface of the metal block to be cut; and an excitation means for applying ultrasonic vibration to one of these cutting tools; , a moving means for bringing the metal block and the pair of cutting tools closer to each other, and a rotational drive means for relatively rotating the metal block and the pair of cutting tools so that cutting is performed on their contact surfaces. Manufacturing equipment characterized by: