JPS6217090A - Manufacture of current collecting material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a current collecting material for pantograph sliders, trolley wheels, and the like.

(Prior art) The current collecting material includes cast alloys, sintered alloys, carbon materials, etc. Among these, carbon materials have excellent arc resistance and self-lubricating properties, and are suitable for mating materials such as trolley wires and power supply rails. while having the advantage of reducing wear and tear.

It has the drawbacks of low mechanical strength and wear resistance, high single-air resistance, and easy generation of heat during current collection. In order to improve this, it has been proposed that the carbon material is impregnated with copper-lead, bits, and various other metals. On the other hand, the usage conditions for current collecting materials have recently become more severe due to higher speeds of railway vehicles, increased current collecting capacity, etc., and pantograph sliders with better wear resistance and current collecting properties are required. Among these, the metal-impregnated carbon material holds great promise.

(Problems to be Solved by the Invention) However, as the metal content of metal-impregnated carbon materials increases, the properties of metal materials appear, and the inherent advantages of carbon decrease.
This has problems such as increased wear due to deterioration of sliding characteristics and increased damage to the trolley wire.

An object of the present invention is to provide a method for producing a current collecting material that eliminates the above-mentioned drawbacks.

(Means for Solving the Problems) The present invention involves extrusion molding a mixed material obtained by kneading 0.5 to 10% by weight of inorganic solid lubricant powder and aggregate and binder, the remainder of which is carbon powder. The present invention also relates to a method for producing a current collecting material, which is characterized by firing, followed by metal impregnation.

In the present invention, carbon powder is the result of coal-based or petroleum-based pitch coke, natural or artificial graphite powder, carbon blank, etc., and mixtures thereof, and the carbon powder and molybdenum disulfide, tungsten diselenide, boron nitride Powders of inorganic solid lubricants such as 100% inorganic solid lubricants are mixed in a mixer or the like to form aggregates.

The above-mentioned inorganic solid lubricant contributes to improving the lubricity of the current collection material, and if it is less than 0.5% by weight, it is ineffective, and if it exceeds 10% by weight, it causes a decrease in mechanical strength, deterioration of current collection performance, etc. There are no particular restrictions on the particle size of the inorganic solid lubricant, but it is more effective if it is smaller than the carbon powder, which is the main component.

In addition to pitch and tar, thermosetting resins such as phenol resins may be used as the binding material.

The kneading, extrusion molding, and firing of the aggregate and binder are performed by known methods, and the content is not limited to 9%.

The metal to be impregnated after firing is preferably one with excellent conductivity and/or lubricity, such as ordinary steel or antimony.

Babbitt, copper-lead mixtures, etc. are used, but are not limited thereto. For modern impregnation, a known method of applying pressure after impregnating under reduced pressure is preferred.

(Example) Next, an example will be described.

Example 1 94.5 parts by weight of pitch coke powder obtained by crushing pitch coke (Nippon Steel Kagaku Ura, trade name LPC-A) to 150 μm or less using an impact crusher, coke-based artificial graphite powder (homemade) crushed to 100 μm or less 41 parts by weight of Tarvituna (manufactured by Yotetsu Kagaku Co., Ltd., trade name PK-L) was added as a binder to aggregate prepared by mixing 5 parts by weight and 0.5 parts by weight of molybdenum disulfide powder of 20 μm or less in a V-type mixer. After kneading at 150° C. for 2 hours using a kneading machine with a warner, a molded product of 35φ×10×100J was obtained using a ram extruder.

This molded body was heated at 25°/hour up to 500°C in a nitrogen gas atmosphere furnace (5°/hour from SOO°C to 1000°C).
The temperature was raised at a rate of 1,000°C and firing was performed.

This fired product was placed in an autoclave, the pressure was reduced to 10 mmHg or less, and the pressure was maintained for 1 hour, after which a molten metal (700°C) of an alloy consisting of 40% by weight of copper and 60% by weight of tin was poured into the autoclave.

A current collecting material was obtained by impregnation under pressure of 45 kg/cm'' for 30 minutes.

Example 2 A current collector material was obtained in exactly the same manner as in Example 1, except that the pitch coke powder in Example 1 was changed to 92 parts by weight, the lead forming powder was changed to 5 parts by weight, and the molybdenum disulfide powder was changed to 3 parts by weight. .

Example 3 The same procedure as in Example 1 was carried out except that the pitch coke powder in Example 1 was changed to 90 parts by weight, the lead forming powder was changed to 5 parts by weight, the molybdenum disulfide powder was changed to 5 parts by weight, and the tar pitch was changed to 425 parts by weight. A current collecting material was obtained.

Example 4 The same procedure as in Example 1 was carried out except that the pitch coke powder in Example 1 was changed to 85 parts by weight, the 99 lead forming powder was changed to 5 parts by weight, the molybdenum disulfide powder was changed to 10 parts by weight, and the tar pitch was changed to 45 parts by weight. A current collecting material was obtained.

Example 5 The pitch coke powder in Example 1 was changed to 100 μm or less, 90 parts by weight. A current collecting material was obtained in the same manner as in Example 1.

Comparative Example 1 Collected in the same manner as in Example 1 except that 95 parts by weight of pitch coke powder, 5 parts by weight of lead-forming powder, no molybdenum disulfide powder, and 40 parts by weight of tar pitch. Obtained electrical materials.

Comparative Example 2 Powders of 8% tin, 1.2% iron, 3% nickel, 4% graphite, and the balance copper were mixed and compression molded at a pressure of 4.5 mm/d to a thickness of 12 mm. @50mm x length 100m
The molded body was sintered at 850° C. in a hydrogen gas atmosphere to obtain a sintered alloy current collector material.

From each current collector material obtained in the above examples and comparative examples, a 10 mm square x 60 mm length (excluding comparative example 2, the length is l
A test piece was cut out in the direction), and the electrical resistivity in the extrusion direction and the mechanical properties (bending strength and hardness) in the direction perpendicular to the extrusion direction were measured. On the other hand, thickness 10mm x width 25 on
A test piece with a length of 60 mm (excluding Comparative Example 2, the length is the extrusion direction during molding) was cut out, and was pressed against a hard copper mating material with a pressure of 7.5 kg using a simulated current collector wear tester, and then subjected to a direct current of 100 A. A sliding test was carried out at a speed of 601 an hour by applying an electric current, and the specific wear 'Ji was determined using the following formula. In addition, the disconnection rate (
The percentage of non-contact time between the test piece and the mating material was determined.

The above measurement results and test results are shown in Table 1 and FIG.

It can be seen from Table 1 that the specific wear amount of the examples is smaller than that of the comparative examples. In Comparative Example 2, welding traces were observed on the surface of the mating material, and it is thought that the specific wear amount increased due to the occurrence of this bath adhesion phenomenon.

As shown in FIG. 1, the disconnection rate of the example is less than 1/2 of that of comparative example 1. Although it is not shown in Comparative Example 2, it was about 10 times that of Example.

(Effects of the Invention) According to the present invention, a current collecting material with excellent wear resistance and no damage to the mating material can be obtained.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between operating time and track loss rate. Agent Patent Attorney Kunihiko Wakabayashi Etengin coin (now) 'S-1 area

Claims (1)

[Claims] 1. A kneaded mixture of 0.5 to 10% by weight of inorganic solid lubricant powder and aggregate and binder, the remainder of which is carbon powder, is extruded and fired, and then metal impregnated. A method for producing a current collecting material characterized by: 2. The method for producing a current collector material according to claim 1, wherein the inorganic solid lubricant powder is molybdenum disulfide powder.