JPH02259002A - Manufacture of copper flake for brake material - Google Patents

Abstract

PURPOSE:To utilize waste material of communication cable and to manufacture copper flake at a low cost by shredding waste copper wire having fine diameter into minute size and rolling after separating only the minute copper wire. CONSTITUTION:After shedding or crushing the copper wire material 1 of copper wire, plated copper wire, enameled copper wire, coated copper wire, etc., to less than the prescribed diameter or length, this is rolled, or after rolling, this is shredded or crushed to less than the prescribed diameter or length. In this result, the copper flake, which is suitable as friction coefficient adjusting material, can be obtd. without spending so much manufacturing cost. Particularly, as the copper wire material for raw material, in the case of using the waste material, such as nugget layer in recovery electric wire in market of communication cable, this can be manufactured at an extremely low cost and is useful in view point of effective utilization of the resource.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION Field of the Invention The present invention relates to a process for economically producing copper flakes useful as friction and reinforcing materials in various disc brake shoes.

(Prior Art) In recent years, the demand for metal fibers as friction and reinforcing materials used in disc brakes and clutches of automobiles, railway vehicles, industrial machinery, etc. has been rapidly increasing.

Furthermore, as the use of asbestos (asbestos) is currently being heavily regulated from the perspective of environmental pollution, the use of cut wool, which is made by cutting steel wool into short lengths, is being considered as a friction and reinforcing material for brake shoes or brake pads in place of asbestos. There is.

Conventionally, cutting methods such as a wire cutting method and a chatter vibration cutting method have been widely used as a method for producing a large amount of such metal fibers.

(Problems to be Solved by the Invention) However, with these cutting methods, it is difficult to efficiently and inexpensively manufacture fibers of non-ferrous metals such as copper.

In other words, the yield of non-ferrous metal fiber manufacturing using the cutting method is
There was a problem that the price was high because the production capacity was low at about 60% and the production capacity was also low.

In addition, the use of cut wool as a friction material to replace asbestos improves both the disadvantages of asbestos pads, such as an increase in wear rate at high temperatures and a decrease in the coefficient of friction.
Although it has the advantage of improved durability, it has many disadvantages such as being easily rusted, having a low coefficient of friction at low temperatures, and producing unpleasant squeaks and sparks when rubbed.
Instead of such steel fibers, the use of friction materials made of non-ferrous metals such as copper and brass is being considered.

Furthermore, demand for fine copper materials such as copper powder and copper fibers as heat dissipating and heat absorbing additives is increasing because copper has excellent thermal conductivity.

The present invention has been made in view of these points, and an object of the present invention is to provide a method for economically producing copper flakes having excellent various properties using waste materials such as communication cables.

[Structure of the Invention] (Means for Solving the Problems) The first invention is characterized in that scrap copper wire with a minute diameter is cut into minute dimensions, and only the minute copper wires are separated and then rolled. The second invention is characterized in that scrap copper wire with a minute diameter is rolled and then cut into minute pieces, and then only the copper flakes are separated.

The minute diameter scrap copper wire used in the present invention includes, for example, an electric wire with an outer diameter of 0.9 or less and a diameter of 0.1 or more, bare scrap copper wire generated in the cable manufacturing process, scrap plated copper wire, In addition to scrap enamel-baked copper wire, scrap coated copper wire, scrap copper wire such as nugget scraps from wires collected in the fabric of communication cables are used.

In particular, recovered wires from communication cables have uniform wire diameters and can be obtained in sufficient quantities at one time, so by using them, copper flakes with stable dimensions, shapes, and quality can be produced at low cost and in large quantities. It has the advantage that it can be manufactured in

In the present invention, in order to cut or crush these copper wire rods and rolled steel materials, the copper materials aligned in the same direction are fed at a constant speed into a cutting machine having a cutting blade, and cut into short pieces with the same length. A method of crushing these copper wire materials using a rotary crusher, etc. can be adopted.

The final length of the copper flakes is approximately t-tom+n, preferably about 3 mm.

The rotary type crusher described above is configured to crush copper wire between, for example, a fixed blade embedded in the inner peripheral surface of a crushing container and a rotary blade that rotates continuously inside the container. A grinder can be used.

In the present invention, sieving is usually used to separate the copper wire and copper flakes after cutting or crushing.

Sieving is performed by passing through a sieve with a predetermined mesh, but especially when crushing is performed using a rotary type crusher with the above structure, such a sieve (screen) is placed at the bottom of the crusher container. It is preferable to continuously crush the copper material provided and introduced until it becomes less than a certain diameter or length.

In the present invention, in order to roll the cut or crushed and sieved fine copper material or the raw material copper wire material before being cut, these materials are rolled between a pair of opposing rolling rolls or pressure presses. A method of sending is adopted.

At this time, a trough-like feeder with grooves parallel to the input direction and vibrating in the direction of the parentheses is placed at the material input port of the rolling roll or pressure press, and the copper materials are fed in in a state in which they are lined up and stacked in the same direction. It is desirable to prevent this from happening.

Further, as the rolling roll, a grooved roll having grooves formed on the surface can also be used.

When such a grooved roll is used, the grooves are transferred to the surface of the copper flakes to form irregularities. Therefore,
Copper flakes whose bonding strength is further improved when mixed with resin etc. can be obtained.

In the present invention, depending on the type of copper wire used, it is either cut or crushed, sieved through a sieve having a predetermined mesh, and then rolled, or rolled, then cut or crushed, and then sieved. However, especially when using coated copper wire scraps such as nugget scraps from recovered wires from communication cables, the above-mentioned rotary crusher is used to crush and sieve. After that, it is suitable to use a method of rolling.

In other words, when scrap coated copper wire cut to an appropriate length is directly fed into a rotary crusher, the resin coating is stripped off by friction between the rotating blades and the screen during crushing, and the resin of the brackets is removed. The coating is clearly separated from the copper plating powder due to the difference in specific gravity.

Therefore, even if the rolling process is performed as it is, copper flakes with good properties can be obtained without contamination with resin coating or the like.

(Function) In the method for producing copper flakes for brake polishing of the present invention, copper wire material such as copper wire, plated copper wire, enameled copper wire, coated copper wire, etc. is cut until it has a predetermined diameter or length or less. Copper flakes are crushed and then rolled, or rolled and then cut or crushed until they have a predetermined diameter or length, making it possible to produce copper flakes suitable as a friction coefficient adjusting material without incurring much manufacturing cost. Obtainable.

In particular, when discontinued publications such as Nugget scraps from the midline recovered wires of communication cables are used as the raw material for copper wire, it can be produced at an extremely low cost and is also useful from the standpoint of effective use of resources.

Further, the raw material copper wire rod has extremely high ductility, making it easy to roll, and since the copper purity is extremely high, copper flakes with good friction properties as a brake can be obtained.

Furthermore, since the obtained copper flakes have a large specific surface area, they have the advantage of high adhesion and bonding strength when mixed with a base material such as a resin.

Furthermore, since the copper flakes obtained by the method of the present invention are work-hardened by rolling, they have greater mechanical strength and a greater reinforcing effect than fine preparations obtained by cutting methods or the like.

(Example) Embodiments of the present invention will be described below based on the drawings.

In this example, first, as shown in FIG.
Scrap copper wire of m or more, scrap plated copper wire, scrap enameled copper wire,
Alternatively, a copper sheath material 1 such as nugget scraps from a midline recovery wire of a communication cable is fed into a rotary crusher 2 from an input hopper 3.

In addition, when using the midline recovery wire of the communication cable,
First, this is cut to a length of about 2I11, the sheath is stripped off, only the strands are taken out, and this is further cut to a length of about 30CIIl and the wire is introduced.

This rotary crusher 2 includes an input hopper 3, a crushing container 4 connected to this, and "+, -1-, (8Y").
A plurality of fixed blades 5 are embedded in the inner wall surface of the crushing container 4, and cutting blades 6 are provided radially protruding in a plurality of directions on a vertical plane, and a rotating blade rotates around a horizontal axis inside the crushing container 4. With child 7,
It consists of a sieve-like bottom plate 8 which is fixed to the bottom of the crushing container 4 and has a mesh of a predetermined size formed thereon.

The copper skin material 1 introduced into the crusher 2 is crushed between the cutting blade 6 and the fixed blade 5 rotating in the crushing container 4 until it reaches a size that can pass through the mesh of the sieve-like bottom plate 8.

Note that the resin coating of the scrap-coated copper wire, such as the median collection wire of a communication cable, is stripped off by being rubbed between the cutting blade 6 and the sieve-shaped bottom plate 8 during crushing. After this resin coating passes through the mesh together with the crushed copper powder, it is clearly separated from the crushed copper powder due to the difference in specific gravity.

The sieve-like bottom plate 8 is crushed to a certain diameter or length or less.
The crushed copper powder that has passed through the mesh is then further sieved by a vibrating sieve 9 placed directly below the pulverizer 2. This vibrating sieve 9 has a mesh set so as to have a desired opening diameter limit, and only the crushed copper powder that passes through this mesh is collected and sent to the rolling mill for the next process.

As shown in FIG. 2, the rolling mill includes a pair of rolling rolls 10 arranged opposite to each other, and a material inlet of the 10 pairs of rolling rolls that is arranged to be inclined in the vertical direction and vibrates minutely in the feeding direction. It is composed of a gutter-shaped feeder 11.

By passing through such rolling rolls, the crushed copper powder 12 is easily rolled to obtain fine flaky copper pieces.

Since the copper flakes thus obtained have a larger specific surface area than copper powder, copper grains, etc., when mixed with a base material such as a resin, the bonding strength is high and separation does not occur.

Moreover, since it is rolled by the rolling rolls 10 and work-hardened, it has a higher mechanical strength and is more effective as a reinforcing material than a fine preparation obtained by cutting or the like.

Further, the copper sheath material 1 used as a raw material, such as bare scrap copper wire and electric wire recovered from inside a communication cable, has extremely high copper purity, and therefore has extremely good characteristics as a conductive material.

In the above embodiment, a rotary type crusher 2 is used.
Although the crushing was carried out using a cutting machine shown below, it is also possible to cut the copper skin material into short pieces in the length direction using a cutting machine having the structure shown below.

In other words, as shown in FIG. 3, the cutting machine has a fixed blade 13 embedded in the lower surface of the material input section, and cutting blades 14 that protrude radially in a plurality of directions on a vertical plane and cut around a horizontal axis. In front of this cutting machine 16, there are a plurality of pairs of feed rollers 17 on a nearly horizontal feeding path.
and a holding roller 18 are provided. Then, the relatively long copper skin material 19 is fed to the fixed blade 13 at a constant speed while aligning the direction with the feed roller 17 and the holding roller 18.
and the rotary blade 14, and are configured to continuously cut it into short pieces.

When using the cutting machine 16 having such a structure, the length axes of the copper skin material 19 are aligned in the direction of travel and fed, so that short steel fibers with good properties without any bending can be obtained. .

Further, in the examples, cutting or crushing was performed until the diameter was a certain value or less, and then rolling processing was performed, but the present invention is not limited to such a method. , and finally pass through a sieve having a predetermined mesh.

[Effects of the Invention] As explained above, according to the method for producing copper flakes for brake abrasive of the present invention, copper sheath materials such as scrap copper wires and communication cables collected in cars are used as raw materials, and brake It is possible to efficiently produce copper flakes that have good frictional properties and high bonding strength to a base material such as a resin.

Therefore, manufacturing costs can be significantly reduced,
It can also be said to be an extremely useful method from the perspective of effective use of resources.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing a rotary crusher used in an embodiment of the present invention, FIG. 2 is a diagram schematically showing a rolling mill used in an embodiment of the present invention, and FIG. FIG. 3 is a diagram schematically showing a cutting machine used in another embodiment of the invention. 1... Copper skin material 2... Rotary crusher layer 5... Fixed blade 6... Cutting blade 8... Sieve-shaped bottom plate 9... Vibrating sieve 10... Rolling roll 11...・Gutter-shaped vibrating feeder 16... Cutting machine Applicant: Showa Cable and Wire Co., Ltd. Patent attorney: Su 111 (and 1 other person) /ρ Figure

Claims (2)

[Claims] (1) A method for producing copper flakes for brake materials, which comprises cutting minute-diameter scrap copper wire or scrap coated copper wire into tiny pieces, separating only the tiny copper wires, and then rolling them. (2) A method for producing copper flakes for brake materials, which comprises rolling scrap copper wire or scrap coated copper wire of minute diameter, cutting the wire into minute pieces, and then separating only the copper flakes.