JP2016226180A - Conductive slide member, manufacturing method thereof, and alternator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive slide member which is capable of suppressing exfoliation of a base material and a conductive layer and improves slidability and conductivity.SOLUTION: The conductive slide member comprises: a base material containing carbon fibers and graphite in a matrix; and one or more conductive layers which are disposed in the base material in a layered state, contain a metal as a main component and regularly include a plurality of openings that penetrate from a front side to a rear side. The conductive layer is embedded in the base material in such a manner that the plurality of openings are filled with the materials that form the base material, and end faces of the one or more conductive layers are exposed at least on a sliding surface. It is preferable that the one or more conductive layers are disposed substantially vertically to the sliding surface. It is also preferable that the conductive layer is formed by arranging wires in a stripe shape or a mesh shape. It is further preferable that the wire is disposed to be tilted relatively to the sliding surface. It is preferable that the plurality of conductive layers are disposed substantially in parallel and at substantially equal intervals. It is also preferable that the metal is copper or copper alloy.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a conductive sliding member, a manufacturing method thereof, and an alternator.

  Carbon brushes, which are conductive sliding members having slidability and conductivity, are used for generators such as alternators and motor brushes. This carbon brush generally contains a binder resin and graphite, and a metal powder such as copper (see, for example, JP-A-10-134922). These conductive sliding members such as carbon brushes are required to have high slidability and improved conductivity in order to improve the efficiency of the above-mentioned generators and motors. Life expectancy is required.

  Here, as a method of improving the conductivity of the carbon brush, a method of increasing the content of the metal powder can be considered. However, the microstructure of the carbon brush is formed by irregularly and independently dispersing components having different properties such as a binder resin and graphite having a large specific resistance and conductive metal powder having a low specific resistance. That is, in the carbon brush, the current path is not formed by arranging the contained metal powder in one direction. For this reason, it is difficult to improve the conductivity of the carbon brush even when the content of the metal powder is increased. On the other hand, the wear resistance is decreased due to an increase in contact resistance, and the vibration and noise of the brush are increased. May occur.

  Therefore, as another method for improving the conductivity of the carbon brush, for example, a method has been proposed in which a conductive layer such as a metal foil or a metal net is bonded to a base material mainly composed of carbon with an adhesive or the like (Japanese Patent Laid-Open No. Hei. 10-23717). However, this method tends to improve the conductivity of the carbon brush, but there is a possibility that the base material and the conductive layer are peeled off due to the strength of the adhesive being reduced due to heat generation during use. Further, when a metal net is used as the conductive layer, the adhesiveness is remarkably lowered due to the adhesive being accumulated in the net, and as a result, the base material and the conductive layer may be more easily separated.

  In order to suppress the peeling between the base material and the conductive layer, a carbon brush using a corrugated metal net as a conductive layer has also been proposed (see Japanese Patent Application Laid-Open No. 56-24777). This carbon brush is said to be easily combined with the components of the substrate by making the metal net corrugated. However, the carbon brush tends to generate a location where a plurality of metal meshes do not contact each other via a base material, and there is a possibility that peeling between the base material and the metal mesh may occur due to the location where the metal meshes contact each other. This is particularly noticeable when the size of the carbon brush is reduced. Furthermore, since the carbon brush has a complicated metal mesh shape, it is difficult to dispose the metal mesh at equal intervals in the substrate. Therefore, in the carbon brush, the position and area of the metal net exposed on the sliding surface may change due to wear accompanying use, and the electric resistance may vary.

Japanese Patent Laid-Open No. 10-134921 Japanese Patent Laid-Open No. 10-23717 JP-A-56-24777

  The present invention has been made based on the above circumstances, and an object thereof is to provide a conductive sliding member that can suppress peeling between the base material and the conductive layer and is excellent in slidability and conductivity. There is to do.

  The invention made in order to solve the above problems includes a base material containing carbon fibers and graphite in a matrix, and a plurality of openings arranged in layers in the base material, the main component of which is metal, and penetrating the front and back sides. One or a plurality of conductive layers having a regular structure, and the conductive layer is buried in the base material so that a plurality of openings are filled with a material constituting the base material, The conductive sliding member has an end surface of the layer exposed at least on the sliding surface.

  In the conductive sliding member, a conductive layer containing a metal as a main component is buried in a base material, and an end surface of the conductive layer is exposed on the sliding surface. The conductive sliding member is excellent in conductivity because the conductive layer serves as a current path that is physically continuous from the sliding surface. The conductive layer regularly has a plurality of openings penetrating the front and back, and the plurality of openings are filled with a material constituting the base material. Therefore, the conductive sliding member is excellent in slidability because it easily maintains the content of graphite, which is a component that improves the slidability, even if the area and the number of layers of the conductive layer are increased. Further, in the conductive sliding member, the carbon fiber filled in the opening can be entangled with the frame of the conductive layer surrounding the opening, and as a result, peeling between the conductive layer and the base material layer is suppressed. The

  The one or more conductive layers may be disposed substantially perpendicular to the sliding surface. As described above, since the one or more conductive layers are disposed substantially perpendicular to the sliding surface, a current path can be shortened when wiring is connected to the surface opposite to the sliding surface. The conductivity can be further improved.

  The conductive layer may be formed by arranging the wires in a stripe shape or a net shape. Wires arranged in stripes or nets are easily available and easy to handle during production. Therefore, the manufacturing cost can be reduced by forming the conductive layer in which the wires are arranged in stripes or nets.

  The wire may be arranged so as to be inclined with respect to the sliding surface. As described above, the wire rod is disposed so as to be inclined with respect to the sliding surface, so that the position where the wire rod is exposed on the sliding surface changes with wear of the conductive sliding member. Therefore, it is possible to suppress adhesive wear at a specific position of the counterpart material.

  The plurality of conductive layers may be arranged substantially parallel and at substantially equal intervals. As described above, since the plurality of conductive layers are arranged substantially in parallel and at substantially equal intervals, even if the contact position with the counterpart material changes due to wear or the like, the electric resistance hardly changes. Moreover, since the location where several conductive layers contact without interposing a base material can be reduced, peeling of a base material and a conductive layer can be suppressed more.

  The metal may be copper or a copper alloy. Thus, the conductivity and the slidability can be further improved when the metal is copper or a copper alloy that is excellent in conductivity and is moderately soft and hardly damages the counterpart material. Moreover, since copper or a copper alloy is comparatively cheap, manufacturing cost can also be reduced.

  The main component of the matrix is preferably a phenol resin. Thus, slidability and electrical conductivity can be further improved because the main component of the matrix is a phenol resin excellent in strength and heat resistance.

  The carbon fiber is preferably a pitch-based carbon fiber. It is considered that pitch-based carbon fibers improve the sliding of the sliding surface by tar exuding due to heat generated during sliding. Therefore, it is considered that the slidability can be further improved when the carbon fiber is a pitch-based carbon fiber.

  Another invention made to solve the above-described problems is an alternator that includes a carbon brush including the conductive sliding member and is used under conditions where the carbon brush is at 70 ° C. or higher.

  The alternator includes the conductive sliding member in which the carbon brush can suppress peeling between the base material and the conductive layer, and is excellent in slidability and conductivity. Therefore, the alternator is excellent in power generation efficiency and has a long life. In addition, the alternator maintains a long life even when used at a relatively high temperature of 70 ° C. or higher because the conductive sliding member can suppress peeling between the conductive layer and the substrate without using an adhesive. Easy to do.

  Still another invention made in order to solve the above-mentioned problems is a base material containing carbon fibers and graphite in a matrix, and is arranged in a layer form in the base material. It is a manufacturing method of an electroconductive sliding member provided with one or a plurality of conductive layers which have a plurality of openings regularly, Comprising: A plurality of base material layers which constitute the above-mentioned base material, and the above-mentioned one or a plurality of conductive layers The process of alternately laminating | stacking and the process of thermocompression-bonding the laminated body after the said lamination | stacking process are provided.

  The manufacturing method of the said electroconductive sliding member can suppress peeling with a base material and an electroconductive layer, and can provide the electroconductive sliding member excellent in slidability and electroconductivity easily and reliably.

  Here, the “matrix” is a concept including what functions as a binder. The “main component” is a component having the largest content, for example, a component having a content of 50% by mass or more. “Embedded in the substrate” means that the surface area of the region exposed from the substrate is less than 50% of the total surface area. “Substantially perpendicular” means that the angle formed is between 80 ° and 100 °. “Substantially parallel” means that the angle formed is within ± 10 °. “Substantially equidistant” means that the difference between the maximum value and the minimum value of the interval of any ten points is within 10% of the average value. “Condition of 70 ° C. or higher” refers to a condition that may be 70 ° C. or higher at least instantaneously.

  According to the conductive sliding member and the manufacturing method thereof, it is possible to provide a conductive sliding member that can suppress the peeling between the base material and the conductive layer and is excellent in slidability and conductivity. The alternator is excellent in power generation efficiency and has a long life.

It is a typical front view which shows the sliding surface of one Embodiment of the electroconductive sliding member of this invention. It is a typical partial enlarged view of the conductive layer and base material of FIG. It is a typical partial expanded sectional view in the X1-X1 line | wire of FIG. It is a typical top view which shows the thrust test apparatus used in the Example of this invention. FIG. 4B is a schematic front view of FIG. 4A. It is a typical top view explaining the electroconductive sliding member used in the Example of this invention, and the terminal of a low resistivity meter.

  Hereinafter, the conductive sliding member, the manufacturing method thereof, and the alternator of the present invention will be described. In addition, as long as there is no notice in particular, the material illustrated below may be used individually by 1 type, and may use 2 or more types together.

<Conductive sliding member>
The conductive sliding member shown in FIGS. 1 to 3 includes a base material 1 and a metal net 2 as a plurality of conductive layers arranged in layers in the base material 1. The metal net 2 regularly has a net 3 as a plurality of openings penetrating the front and back. The metal net 2 is embedded in the base material 1 so that a plurality of meshes 3 are filled with the material constituting the base material 1. The end surfaces of the plurality of metal nets 2 are exposed at least on the sliding surface.

  The shape of the conductive sliding member is a rectangular parallelepiped, and the square surface where the end faces of the plurality of metal nets 2 shown in FIG. 1 are exposed is the sliding surface, and this sliding surface comes into contact with the mating member during use. . However, the shape of the conductive sliding member is not limited to a rectangular parallelepiped shape, and may be, for example, a prismatic shape such as a triangular prism shape, a pentagonal prism shape, or a cylindrical shape. The shape of the sliding surface is not limited to a square shape, and may be, for example, a triangular shape, a polygonal shape such as a pentagonal shape, a circular shape, an elliptical shape, or the like. Further, the sliding surface may be a flat surface or a curved surface. Further, the conductive sliding member may have a plurality of sliding surfaces. In this case, the conductive sliding member may be used with only one sliding surface in contact with the mating member, or with a plurality of sliding surfaces in contact with one or more mating members. May be. Moreover, you may use the area | region which is not contact | abutting with the other party material in the said sliding surface for another uses, such as connection of wiring, fixation of the said electroconductive sliding member.

  The average length of one side when the sliding surface is polygonal and the average diameter when the sliding surface is circular are not particularly limited, and can be changed as appropriate according to the application. The lower limit of the average length or average diameter of the one side is usually 0.2 mm, preferably 1 mm, and more preferably 3 mm. On the other hand, the upper limit of the average length or average diameter of the one side of the sliding surface is usually 100 mm, preferably 20 mm, and more preferably 10 mm. When the average length or average diameter of the one side is smaller than the lower limit, the area of the sliding surface is reduced, and there is a possibility that the conductivity and the sliding property are lowered. Conversely, when the average length or average diameter of the one side exceeds the upper limit, it may be difficult to use it for a small device.

  The average length in the direction perpendicular to the sliding surface of the conductive sliding member is not particularly limited, and is, for example, 0.2 mm or more and 100 mm or less.

(Base material)
The base material 1 contains carbon fibers and graphite in a matrix. The base material 1 may contain other arbitrary components as long as the effects of the present invention are not impaired.

  As a minimum of content of a matrix in substrate 1, 3 mass% is preferred, 7 mass% is more preferred, and 10 mass% is still more preferred. On the other hand, the upper limit of the content of the matrix is preferably 40% by mass, more preferably 25% by mass, and still more preferably 20% by mass. When the content of the matrix is smaller than the lower limit, it may be difficult to form the conductive sliding member. On the other hand, when the content of the matrix exceeds the above upper limit, the slidability of the conductive sliding member may be deteriorated, and the peeling between the metal net 2 and the substrate 1 may not be sufficiently suppressed.

〔matrix〕
The matrix shapes the substrate 1. Examples of the main component of the matrix include thermosetting resins such as phenol resins and epoxy resins, thermoplastic resins such as PPS (polyphenylene sulfide) and PEEK (polyether ether ketone), pitch, and tar. Of these, the main component of the matrix is preferably a thermosetting resin from the viewpoint of strength and heat resistance, and more preferably a phenol resin. The lower limit of the total content of the above-described thermosetting resin, thermoplastic resin, pitch and tar in the matrix is preferably 80% by mass, and more preferably 90% by mass. The total content may be 100% by mass.

[Phenolic resin]
A phenolic resin is an insoluble and infusible resin in which a three-dimensional cross-linked structure is formed in the molecule, and an oligomer made of phenols and aldehydes (hereinafter also referred to as “uncured phenol resin”) is cured. Can be obtained. This uncured phenol resin may be solid or liquid. Examples of the phenol resin include novolac type phenol resins and resol type phenol resins. Examples of the resol type phenol resin include methylol type phenol resin, dimethylene ether type phenol resin and the like, and dimethylene ether type phenol resin is preferable from the viewpoint of suppressing chipping during processing. Among these, a novolac type phenol resin is preferable from the viewpoint of improving the slidability of the conductive sliding member.

  Examples of the phenols include cresol, ethylphenol, xylenol, pt-butylphenol, octylphenol, nonylphenol, dodecylphenol, alkylphenols such as p-phenylphenol, and phenol, among which phenol is preferable.

  Examples of the aldehydes include formalin and paraformaldehyde, among which formalin is preferable.

  As a minimum of number average molecular weight (Mn) of an uncured phenol resin, 400 is preferred, 450 is more preferred, and 500 is still more preferred. On the other hand, the upper limit of Mn of the uncured phenol resin is preferably 1,200, more preferably 800, and even more preferably 600. When the number average molecular weight of the uncured phenol resin is less than the above lower limit or exceeds the above upper limit, the heat shock resistance of the conductive sliding member may be lowered. In addition, the number average molecular weight of an uncured phenol resin and the weight average molecular weight described later are values measured by an area method of gel filtration chromatograph.

  The weight average molecular weight (Mw) of the uncured phenol resin is preferably 400, more preferably 1,500, and even more preferably 3,000. On the other hand, the upper limit of the Mw of the uncured phenol resin is preferably 5,000, more preferably 4,500, and still more preferably 4,000. When the Mw of the uncured phenol resin is smaller than the above lower limit or exceeds the above upper limit, the stability and moldability of the molding material may be lowered.

  The dispersion ratio (Mw / Mn) of the uncured phenol resin is preferably 1.1, more preferably 4.0, and even more preferably 7.0. On the other hand, the upper limit of the dispersion ratio of the uncured phenol resin is preferably 20.0, more preferably 12.0, and even more preferably 8.0. When the dispersion ratio of the uncured phenol resin is smaller than the lower limit or exceeds the upper limit, the stability and moldability of the molding material may be reduced.

  The uncured phenol resin may contain monomers and dimers of the above phenols. The upper limit of the total content of the monomers and dimers of the phenols in the uncured phenol resin is preferably 10% by mass and more preferably 5% by mass. When the total content of the phenolic monomer and dimer exceeds the above upper limit, there is a fear that the friction coefficient of the conductive sliding member is increased and the wear amount is increased. Moreover, the heat resistance of the said electroconductive sliding member and dimensional accuracy can be improved by making the total content of the monomer and dimer of the said phenol into the said range. Further, the total content of the monomers and dimers of the phenols may be 0% by mass. The total content of the phenolic monomer and dimer is a value measured by gel filtration chromatography.

  Among them, the uncured phenol resin has a total content of phenolic monomers and dimers of 10% by mass or less, and the dispersion ratio (Mw / Mn) is particularly preferably 1.5 or more and 20 or less. preferable. Thus, by making the total content of the phenolic monomer and dimer and the dispersion ratio (Mw / Mn) in the above range, the friction coefficient of the conductive sliding member can be further reduced, As a result, the amount of wear can be further reduced. Further, by setting both the total content and the dispersion ratio in the above range, the melt viscosity can be kept relatively low even if the total content of the phenolic monomer and the dimer is 10% by mass or less.

  Examples of a method for synthesizing an uncured phenol resin include a step of preparing a mixed solution of the above phenols, aldehydes and catalyst (preparation step), a step of subjecting the mixed solution to a condensation reaction at a reflux temperature (condensation reaction step), and Examples include a method including a step (removal step) of concentrating the mixed solution after the condensation reaction under reduced pressure.

  When synthesizing an uncured novolak type phenol resin, examples of the catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, organic acids such as oxalic acid, paratoluenesulfonic acid, benzenesulfonic acid, and xylenesulfonic acid, and oxidation. Examples include acid catalysts such as zinc, zinc chloride, magnesium oxide, zinc acetate, and other acidic substances. Among these, organic acids are preferable, and oxalic acid is more preferable. In addition, the molar ratio (F / P) of the aldehydes (F) to the phenols (P) in the mixed solution is, for example, 0.75 or more and 0.95 or less.

  When synthesizing an uncured resol-type phenol resin, examples of the catalyst include alkali catalysts such as alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide. The lower limit of the F / P in the mixed solution is, for example, 1.1 or more and 4.0 or less.

  As content of the said catalyst in the said liquid mixture, it is 0.05 mass part or more and 70 mass parts or less with respect to 100 mass parts of said phenols, for example.

  The reflux temperature in the condensation reaction is, for example, 90 ° C. or higher and 110 ° C. or lower. Moreover, as reaction time of the said condensation reaction, they are 2 hours or more and 12 hours or less, for example.

[Epoxy resin]
The epoxy resin is an insoluble and infusible resin in which a three-dimensional cross-linked structure is formed in the molecule, and an oligomer having an epoxy group (hereinafter also referred to as “uncured epoxy resin”) is cured together with a curing agent. can get. Although it does not specifically limit as an epoxy resin, For example, novolak type epoxy resin, bisphenol-A type epoxy resin, bisphenol-F type epoxy resin, trisphenol methane type epoxy resin, tetrakisphenol type epoxy resin, brominated epoxy resin, dicyclo Examples thereof include pentadiene type epoxy resins, naphthalene type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, and cyclic aliphatic epoxy resins.

〔Carbon fiber〕
The carbon fiber improves the mechanical strength of the conductive sliding member and suppresses the peeling between the base material 1 and the metal net 2 by being entangled with the strands of the metal net 2. Examples of the carbon fiber include PAN-based carbon fiber using polyacrylonitrile (PAN) as a raw material, and pitch-based carbon fiber using pitch as a raw material. The raw material for the pitch-based carbon fiber may be a pitch derived from petroleum or a pitch derived from coal. Of these, pitch-based carbon fibers are preferred as the carbon fibers. The pitch-based carbon fiber improves the sliding of the sliding surface of the conductive sliding member by oozing out tar content due to heat generation during sliding, and as a result, the friction coefficient of the conductive sliding member is changed. Can be stabilized. Moreover, since the pitch-based carbon fiber has a low electrical resistivity, the conductivity of the conductive sliding member can be further improved.

  Although it does not specifically limit as a minimum of the average fiber length of carbon fiber, 0.005 mm is preferable, 0.01 mm is more preferable, 0.05 mm is further more preferable. On the other hand, the upper limit of the average fiber length of the carbon fibers is not particularly limited, but is preferably 1 mm, more preferably 0.7 mm, and further preferably 0.5 mm. When the average fiber length of the carbon fiber is smaller than the lower limit, the mechanical strength of the conductive sliding member may be reduced. On the other hand, when the average fiber length of the carbon fibers exceeds the upper limit, the slidability may be reduced because the carbon fibers are easily peeled off from the conductive sliding member. Moreover, there exists a possibility that suppression of peeling with the base material 1 and the metal net | network 2 may become inadequate.

  As a minimum of the average fiber diameter of carbon fiber, 1 micrometer is preferred and 3 micrometers is more preferred. On the other hand, the upper limit of the average fiber diameter of the carbon fibers is preferably 18 μm, and more preferably 12 μm. When the average fiber diameter of the carbon fiber is smaller than the lower limit, the wear resistance of the conductive sliding member may be reduced. Moreover, since the intensity | strength of carbon fiber falls, there exists a possibility that suppression of peeling with the base material 1 and the metal net | network 2 may become inadequate. On the contrary, when the average fiber diameter of the carbon fiber exceeds the above upper limit, the flexibility of the carbon fiber is lowered and it is difficult to fill the network 3 of the metal net 2, so that the carbon fiber is not easily entangled with the network 3 of the metal net 2. There is a risk. As a result, suppression of peeling between the base material 1 and the metal net 2 becomes insufficient, and the base material 1 and the metal net 2 may be easily peeled off when an impact is applied to the conductive sliding member. .

  As a minimum of content of carbon fiber in substrate 1, 1 mass% is preferred, 3 mass% is more preferred, and 4 mass% is still more preferred. On the other hand, as an upper limit of content of carbon fiber, 20 mass% is preferable, 10 mass% is more preferable, and 7 mass% is further more preferable. When the carbon fiber content is smaller than the above lower limit, the mechanical strength of the conductive sliding member may be insufficient, and the suppression of peeling between the base material 1 and the metal net 2 may be insufficient. Conversely, if the carbon fiber content exceeds the above upper limit, the moldability of the molding material of the conductive sliding member may be reduced.

〔graphite〕
Graphite reduces the coefficient of friction of the conductive sliding member. Although it does not specifically limit as graphite, Natural graphite, artificial graphite, etc., such as spherical graphite, scale-like graphite, lump graphite, and earth-like graphite, etc. are mentioned, for example. Of these, spherical graphite and artificial graphite are preferred as the graphite. Note that graphite is usually in the form of particles, and at least a part of the graphite particles may have a particle size smaller than the average opening of the metal net 2. Here, “at least a part of graphite” means 10% by mass or more of graphite.

  As a minimum of content of graphite in substrate 1, 40 mass% is preferred, 55 mass% is more preferred, and 70 mass% is still more preferred. On the other hand, the upper limit of the graphite content is preferably 90% by mass, and more preferably 85% by mass. When the content of graphite is smaller than the lower limit, the slidability of the conductive sliding member may be reduced. Conversely, if the graphite content exceeds the above upper limit, the moldability of the molding material of the conductive sliding member may be reduced.

  As an arbitrary component which the base material 1 may contain, a metal powder, a solid lubricant, etc. are mentioned, for example. As said metal powder, the metal powder which has copper, silver, tin, gold | metal | money, platinum, palladium, aluminum, these alloys etc. as a main component is mentioned, for example. Examples of the solid lubricant include boron compounds, molybdenum disulfide, and tungsten disulfide. The content of these other components can be changed as appropriate as long as the slidability and conductivity of the conductive sliding member are not impaired. However, when the base material 1 further contains a metal powder, the upper limit of the total mass of the metal powder and the metal net 2 with respect to the mass of the conductive sliding member is preferably 30% by mass, and more preferably 25% by mass. If the upper limit of the total mass exceeds the upper limit, the slidability of the conductive sliding member may be reduced or the weight may be increased unnecessarily.

(Conductive layer)
The conductive sliding member includes a metal net 2 as a conductive layer. In FIG. 1, the number of conductive layers provided in the conductive sliding member is 3, but the number is not limited thereto. The lower limit of the number of the conductive layers is usually 1, preferably 2 and more preferably 3. On the other hand, the upper limit of the number of conductive layers is usually 100, preferably 20, and more preferably 8. When the number of conductive layers is smaller than the lower limit, the conductivity of the conductive sliding member may be reduced. On the other hand, when the number of conductive layers exceeds the above upper limit, there is a possibility that molding into the conductive sliding member may be difficult and the weight may increase unnecessarily.

  As a minimum of an average interval of a plurality of metal nets 2, 0.1 mm is preferred, 0.5 mm is more preferred, and 0.8 mm is still more preferred. On the other hand, the upper limit of the average interval between the plurality of metal nets 2 is preferably 5 mm, more preferably 3 mm, and even more preferably 1.5 mm. When the average interval between the plurality of metal nets 2 is smaller than the above lower limit, the plurality of metal nets 2 are likely to come into contact with each other without the base material 1, and as a result, the base material 1 and the metal net 2 may be easily peeled off. There is. When the average interval between the plurality of metal nets 2 exceeds the upper limit, the conductive sliding member may become unnecessarily large.

(Metal mesh)
The metal net 2 is formed by arranging wire rods mainly composed of metal in a net shape, and regularly has a plurality of rectangular nets 3 penetrating the front and back. The plurality of metal nets 2 are disposed substantially parallel and at substantially equal intervals. Further, the metal net 2 may be disposed substantially perpendicular to the sliding surface, or may be disposed so as to be inclined with respect to the sliding surface, but is substantially perpendicular to the sliding surface. It is preferable that it is disposed.

  The end surfaces of the plurality of metal nets 2 may be exposed at least on the sliding surface as described above, but may be exposed on a surface other than the sliding surface of the conductive sliding member. Thus, when the end surfaces of the plurality of metal nets 2 are exposed on the sliding surface and other surfaces, wiring such as lead wires is electrically connected to the end surfaces of the metal net 2 exposed on the other surfaces. By connecting, a current path through the metal net 2 can be formed between the counterpart material and the wiring. However, the end surfaces of the plurality of metal nets 2 may be exposed only on the sliding surface, and in this case, by providing an insertion hole on the surface other than the sliding surface of the conductive sliding member, Thus, the wiring and the metal net 2 can be electrically connected.

  The metal net 2 may be a woven net (mesh) formed by weaving a wire, or may be formed by bonding the wire with an adhesive or the like. Further, the metal net 2 may have wavy irregularities formed in the thickness direction and may be flat, but is preferably flat.

  As the metal which is the main component of the wire, that is, the metal which is the main component of the metal net 2, silver, copper, aluminum, iron, nickel and alloys thereof are preferable, and copper and copper alloys are more preferable.

  As a minimum of average thickness of metal net 2, 0.05 mm is preferred and 0.15 mm is preferred. On the other hand, the upper limit of the average thickness of the metal net 2 is preferably 1 mm, and more preferably 0.3 mm. When the average thickness of the metal mesh 2 is smaller than the above lower limit, the “average thickness of the metal mesh” herein refers to the average value of the thicknesses measured in the intersecting regions of arbitrary ten points of wire rods.

  Although it does not specifically limit as a cross-sectional shape of the said wire, For example, square shape, rectangular shape, triangular shape, round shape, elliptical shape etc. are mentioned. The lower limit of the average diameter of the wire is preferably 1 μm, more preferably 10 μm, and even more preferably 100 μm. On the other hand, the upper limit of the average diameter of the wire is preferably 500 μm, more preferably 300 μm, and even more preferably 150 μm. When the average diameter of the said wire is smaller than the said minimum, there exists a possibility that the electroconductivity of the said electroconductive sliding member may fall. Conversely, if the average diameter of the wire exceeds the upper limit, adhesive wear may occur when the counterpart material is the same metal material, and the slidability of the conductive sliding member may be reduced. As a result, there is a risk that vibration and sound generated during use may increase. Moreover, it becomes difficult for the carbon fibers to be entangled, and there is a possibility that suppression of peeling between the base material 1 and the metal net 2 becomes insufficient. Here, the “average diameter” means an average value of the diameters of perfect circles having the same area as the cross-sectional area at any ten points orthogonal to the axial direction.

The lower limit of the average opening of the metal net 2 is preferably 50 μm, more preferably 100 μm, and still more preferably 120 μm. On the other hand, the upper limit of the average opening of the metal net 2 is preferably 5,000, more preferably 500 μm, and further preferably 180 μm. Moreover, as a minimum of the average area of the mesh 3 of the metal net 2, 2.5 × 10 ³ μm ² is preferable, 1.0 × 10 ⁴ is more preferable, and 1.5 × 10 ⁴ μm ² is more preferable. On the other hand, the upper limit of the average area of the mesh 3 of the metal net 2 is preferably 2.5 × 10 ⁷ μm ² , more preferably 2.5 × 10 ⁵ , and even more preferably 3.2 × 10 ⁴ μm ² . When the average opening or the average area is smaller than the lower limit, it is difficult to fill the mesh 3 with the material constituting the substrate 1, so that the suppression of peeling between the substrate 1 and the metal mesh 2 by the carbon fiber is insufficient. There is a risk. On the contrary, when the average opening or the average area exceeds the upper limit, the carbon fiber contained in the base material 1 filled in the vicinity of the center of the mesh 3 is difficult to be entangled with the metal network 2. There is a possibility that suppression of peeling with 2 may be insufficient. Moreover, since the size of the metal net 2 increases, the size of the conductive sliding member may increase unnecessarily. Here, the average opening of the metal net 2 refers to a value measured in accordance with “7.2.1 Average Opening” of JIS-G3556 (2001) “Industrial Woven Wire Mesh”. Further, the average area of the mesh 3 of the metal net 2 is an average value of the area of any ten meshes.

  The lower limit of the ratio between the average opening of the metal net 2 and the average fiber diameter of the carbon fibers is preferably 1: 0.001, more preferably 1: 0.01, and still more preferably 1: 0.05. On the other hand, the upper limit of the ratio is preferably 1: 0.5, more preferably 1: 0.3, and still more preferably 1: 0.1. When the ratio is smaller than the lower limit or exceeds the upper limit, peeling between the base material 1 and the metal net 2 may not be sufficiently suppressed.

As a minimum of the number of meshes of metal net 2, 5 mesh is preferred, 30 mesh is more preferred, and 80 mesh is still more preferred. On the other hand, the upper limit of the number of meshes of the metal net 2 is preferably 500 mesh, more preferably 200 mesh, and still more preferably 120 mesh. Here, “mesh” means the number of eyes per side of 25.4 mm (1 inch). For example, 100 mesh means that the number of eyes per side is 100.

  The lower limit of the ratio of the mass of the substrate 1 to the mass of the metal net 2 is preferably 70:30, and more preferably 75:25. On the other hand, the upper limit of the ratio of the mass of the substrate 1 to the mass of the metal net 2 is preferably 97: 3, more preferably 90:10, and even more preferably 85:15. When the ratio of the mass of the base material 1 and the mass of the metal net 2 is smaller than the lower limit, the strength of the conductive sliding member may be reduced or the molding may be difficult. On the contrary, when the ratio of the mass of the base material 1 and the mass of the metal net 2 exceeds the upper limit, the conductivity of the conductive sliding member may be lowered.

  In addition, it is preferable that the said electroconductive sliding member is fixed in the state which contact | abutted the base material 1 and the metal net | network 2 without joining materials, such as an adhesive agent, from a viewpoint of improving heat resistance strength.

<Method for producing conductive sliding member>
The method for producing the conductive sliding member includes a step of laminating a plurality of base material layers constituting the base material and the one or more conductive layers alternately (lamination step), and a laminate after the lamination step. A step of thermocompression bonding (thermocompression bonding step). Hereinafter, each step will be described.

(Lamination process)
In this step, a plurality of substrate layers constituting the substrate and the one or more conductive layers are alternately laminated.

[Base material layer]
The base material layer contains carbon fibers and graphite in a matrix. Moreover, when the main component of the matrix of the base material layer is a thermosetting resin, the thermosetting resin is usually uncured. About the kind and content of carbon fiber and graphite, since it can be the same as that of the base material of the said electroconductive sliding member, description is abbreviate | omitted.

Examples of the method for producing the base material layer include a step of mixing the main component of the matrix, carbon fiber, graphite, and an optional component (mixing step), and a step of press-molding the mixture obtained in the mixing step (processing) Pressure forming step) and the like. In the above production method, the mixture may be pulverized before pressure molding in order to adjust the particle size of graphite. In addition, when the main component of the matrix is not in the form of a solution, each component such as the main component of the matrix is mixed in a solvent such as ethanol in the mixing step, and then the solvent is volatilized before the pressure molding step. Good. In this case, the ratio of the total mass of the above components to the mass of the solvent is, for example, 85:15 or more and 96: 4 or less. Furthermore, in the mixing step, as another method, a mixture may be obtained by kneading and mixing each component such as a main component of the matrix with a pressure kneader, a mixing roll, a twin screw extruder, or the like. The pressure applied in the pressure molding step is, for example, 1 kg / cm ² or more and 1,000 kg / cm ² or less. In addition, when kneading and mixing in the mixing step and / or when the mixture is pulverized before pressure molding, the carbon fiber has a relatively long fiber length in the mixing step because the fiber length of the carbon fiber is reduced by cutting. Can also be used. In this case, the specific average fiber length of the carbon fibers is, for example, 50 μm or more and 6,000 μm or less.

  As a minimum of average thickness of each layer of the above-mentioned base material layer, 0.1 mm is preferred, 0.5 mm is more preferred, and 0.8 mm is still more preferred. On the other hand, the upper limit of the average thickness of each layer of the base material layer is preferably 5 mm, more preferably 3 mm, and even more preferably 1.5 mm. When the average thickness of each layer of the base material layer is smaller than the above lower limit, the average distance of the metal mesh of the conductive sliding member is reduced, and as a result, the metal mesh contacts the base material without going through the base material. And the metal net may be easily peeled off. On the other hand, when the average interval between the layers of the base material layer exceeds the upper limit, the conductive sliding member may become unnecessarily large.

  When the main component of the matrix is an uncured thermosetting resin, it is preferable to further mix a curing agent as an optional component in the mixing step. Examples of the curing agent when the thermosetting resin is a phenol resin include hexamethylenetetramine. Examples of the curing agent when the thermosetting resin is an epoxy resin include polyhydric phenols, acid anhydrides, amines, imidazoles, and the like. The mixing amount of the curing agent is, for example, 10 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the thermosetting resin.

(Thermo-compression process)
In this step, the laminated body after the lamination step is thermocompression bonded. By this step, the metal net is buried in the base material so that the plurality of openings are filled with the material constituting the base material. Moreover, when the main component of the matrix of the base material layer is an uncured thermosetting resin, the thermosetting resin is cured by this step. The thermocompression bonding conditions can be appropriately changed depending on the main component of the matrix, but the heating temperature is, for example, 150 ° C. or more and 230 ° C. or less, and the molding pressure is, for example, 1 kg / cm ² or more and 1,000 kg / cm. ² or less.

  In addition, in the manufacturing method of the said conductive sliding member, you may further process after the said thermocompression-bonding process. Examples of the processing after the thermocompression bonding step include firing for carbonizing the binder, machining for making the conductive sliding member into a specific shape, machining such as grinding, polishing, and the like. . Moreover, when the main component of the matrix of the conductive sliding member is a thermosetting resin, curing (heating) may be performed as processing after the above-described thermocompression bonding step. By performing the curing, the thermosetting resin can be further cured, and as a result, the slidability of the conductive sliding member can be further improved. When curing is performed, the heating temperature can be appropriately changed depending on the type of the thermosetting resin, and is, for example, 160 ° C. or higher and 280 ° C. or lower.

  In the above machining, the end of the metal net may be machined so as to protrude beyond the sliding surface. By such machining, it is possible to easily electrically connect the end of the protruding metal net and the wiring such as the lead wire.

(Use)
Applications of the conductive sliding member include, for example, generators such as alternators, carbon brushes for motors, relays for railway traffic signals, switches such as elevators, small voltage regulators, electrical contacts such as circuit breakers, connectors, switches, etc. Electronic device connection parts, passive parts such as capacitors, and pantograph sliding boards. Among these, the conductive sliding member can be suitably used as a carbon brush, and can be more suitably used as a carbon brush for an alternator. An alternator is a generator for generating electricity by power and is used for automobiles and the like.

<Alternator>
The alternator includes a carbon brush including the conductive sliding member, and is used under a condition where the carbon brush is 70 ° C. or higher. Except for the carbon brush of the alternator, since it can be the same as a conventionally known one, the description is omitted.

  The carbon brush has a wiring such as a lead wire connected to a surface other than the sliding surface of the conductive sliding member. In the conductive sliding member, the end face of the metal net is exposed on the sliding surface with the mating material (commutator), and the wiring and the mating material are electrically connected.

  The wiring may be fixed by making a hole in the conductive sliding member, inserting a lead wire there, and packing metal powder or the like having high conductivity. Alternatively, the lead wire may be fixed by protruding the metal mesh on the surface to which the lead wire is attached and twisting the protruding metal mesh after forming.

  The alternator has excellent power generation efficiency and a long life because the conductive sliding member is excellent in conductivity and sliding property. In addition, the alternator may become 70 ° C. or higher due to frictional heat during use, but the conductive sliding member needs to use a bonding material such as an adhesive to suppress peeling between the base material and the metal net. Therefore, it is easy to improve the heat resistance strength, and as a result, the lifetime is longer.

<Other embodiments>
The present invention is not limited to the configuration of the above-described embodiment, and can be appropriately modified within the intended scope of the present invention.

  The shape of the mesh of the metal mesh is not limited to the rectangular shape in FIG. 3, and may be, for example, a triangular shape, a circular shape, an elliptical shape, or the like.

  The conductive layer is not limited to a metal net, and examples thereof include punching metal and a plurality of wires arranged in a stripe shape. The conductive layer may contain components other than metals such as resin, ceramic, glass, etc., as long as the metal is the main component.

  When the conductive layer is a punching metal, the shape of the opening of the punching metal is not particularly limited. For example, various shapes such as a square shape, a rectangular shape, a rhombus shape, a circular shape, and an oval shape can be adopted. Further, the average area of the openings may be the same as the average area of the mesh of the metal net, for example. Furthermore, the average distance between adjacent openings of the punching metal can be the same as the average diameter of the metal mesh wire, for example. Furthermore, the average thickness of the punching metal can be the same as, for example, the average thickness of the metal mesh described above.

  In the case where the conductive layer is formed by arranging the wire in a stripe shape, the cross-sectional shape and the average diameter of the wire can be the same as those of the metal mesh wire, for example. Moreover, as the space | interval of the said wire, it can be made the same as that of the average opening of a metal net, for example.

  In the case where the conductive layer is formed by disposing the wire in a stripe shape or a net shape, the wire material may be disposed so as to be inclined with respect to the sliding surface. In this case, the inclination angle with respect to the sliding surface of the wire is, for example, 30 ° or more and 60 ° or less.

  The plurality of conductive layers may not be arranged substantially in parallel and at substantially equal intervals.

  The manufacturing method of the said conductive sliding member is not limited to the above-mentioned manufacturing method. Specifically, for example, a method in which one or a plurality of conductive layers are disposed in a mold in injection molding, transfer molding, and the like, and a material for forming a base material is filled in the mold.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by a following example. In the examples, “parts” and “%” indicate “parts by mass” and “% by mass” unless otherwise specified. Moreover, when describing a compounding quantity using a mass part in this specification, it describes as a mass part with respect to 100 mass parts of phenol resins or epoxy resins unless there is particular notice.

(Manufacture of uncured phenolic resin)
In a reaction vessel equipped with a thermometer, a stirrer, and a condenser, 193 parts by mass of phenol (P), 142 parts by mass of 37% by weight formalin (F) (F / P = 0.85), and 0.97 mass of oxalic acid Parts (0.5% by mass / P) were each charged, and the temperature was gradually raised to the reflux temperature (98 ° C. to 102 ° C.), followed by a condensation reaction at the same temperature for 6 hours. Subsequently, when vacuum concentration was performed, 199 parts by mass (yield: 103% by mass / P) of an uncured novolac type phenol resin was obtained. This uncured phenol resin had a weight average molecular weight (Mw) of 3,840, a number average molecular weight (Mn) of 512, and a dispersion ratio (Mw / Mn) of 7.5.

  The above-mentioned weight average molecular weight and number average molecular weight are as follows: Tosoh Corporation gel filtration chromatograph SC-8020 series build-up system (column: G2000Hxl + G4000Hxl, detector: UV254 nm, carrier: tetrahydrofuran 1 mL / min, column temperature: 38 ° C. ) Using standard polystyrene conversion.

Example 1
Graphite (graphite) (“Blue P” from Nippon Graphite Industries Co., Ltd.) 75.0 parts by mass and pitch-based carbon fiber (“K6331T” from Mitsubishi Plastics Chemical Industries, Ltd .; average fiber diameter 11 μm; average fiber length 3,000 μm) 5 A graphite mixture was prepared by dissolving 1.0 part by mass and 13.0 parts by mass of the above-mentioned uncured phenol resin and 2.1 parts by mass of hexamethylenetetramine (curing agent) as a matrix in 7.0 parts by mass of ethanol. . Next, the ethanol was volatilized to dry the graphite mixture. Thereafter, in order to adjust the particle size of the graphite contained, the above graphite mixture was pulverized to produce a treated graphite mixture. This treated graphite mixture was pressure-molded at 180 kg / cm ² to prepare a base material layer shaped into a flat plate having an average thickness of 1 mm. Thereafter, five uncured base material layers (total 80 parts by mass) and four copper meshes as conductive layers (average diameter of wire rods 110 μm, 100 mesh, average aperture 144 μm) (total 20 parts by mass) Were alternately laminated and molded by thermocompression bonding at a temperature of 180 ° C. and a molding pressure of 180 kg / cm ² . Next, the obtained molded product was cured at 250 ° C. and then post-processed to obtain the conductive sliding member of Example 1. In addition, since the said carbon fiber which this electroconductive sliding member contains is cut | disconnected by the grinding | pulverization of the above-mentioned graphite mixture, the average fiber length is about 100 micrometers.

  The conductive sliding member of Example 1 is a rectangular parallelepiped of 5 mm × 5 mm × 3 mm, and a square surface of 5 mm square is a sliding surface. The four copper meshes as the conductive layers provided in the conductive sliding member are arranged substantially parallel to each other and substantially perpendicular to the sliding surface, and the end surfaces are exposed to the sliding surface.

(Example 2)
A conductive sliding member of Example 2 was obtained in the same manner as in Example 1 except that no curing was performed after molding.

Example 3
Instead of pitch-based carbon fiber, 5.0 parts by mass of PAN-based carbon fiber (Torayca T-008A; average fiber diameter 7 μm; average fiber length 3,000 μm) is used as carbon fiber, and curing is performed after molding. The conductive sliding member of Example 3 was obtained in the same manner as in Example 1 except that this was not performed.

Example 4
Uncured epoxy resin instead of uncured phenol resin (Mitsubishi Chemical's "JER871" (main agent) and Mitsubishi Chemical's "JER Cure FL240" (curing agent) mixed at a weight ratio of 100: 20) 16 A conductive sliding member of Example 3 was obtained in the same manner as in Example 1 except that 0.0 part by mass was used and curing was not performed after molding.

(Comparative Example 1)
80.0 parts by mass of graphite (“Blue P” from Nippon Graphite Industries Co., Ltd.), 13.0 parts by mass of the aforementioned uncured phenol resin and 2.1 parts by mass of hexamethylenetetramine (curing agent) as a matrix An electroconductive sliding member of Comparative Example 1 was obtained in the same manner as in Example 1 except that 7.0 mass parts of ethanol was used as a graphite mixture, and no curing was performed after molding.

(Comparative Example 2)
48.0 parts by mass of graphite (“Blue P” from Nippon Graphite Industries Co., Ltd.), 12.0 parts by mass of the above-mentioned uncured phenol resin and 1.9 parts by mass of hexamethylenetetramine (curing agent) as a matrix. A graphite mixture was prepared by mixing with 7.0 parts by mass of ethanol. Next, this ethanol was volatilized and the mixture was dried. Thereafter, in order to adjust the particle size of the graphite contained, the above graphite mixture was pulverized to produce a treated graphite mixture. 40 parts by mass of copper powder (“Copper Powder (Wako First Grade)” manufactured by Wako Pure Chemical Industries, Ltd.) is mixed with 60 parts by mass of this treated graphite mixture, molded at a molding pressure of 3,500 kg / cm ² , and then at 250 ° C. After curing, the conductive sliding member of Comparative Example 2 was obtained by post-processing. The shape of the conductive sliding member of Comparative Example 2 was the same as the shape of the conductive sliding member of Example 1.

<Evaluation>
The slidability and conductivity of the conductive sliding members of Examples 1 to 4 and Comparative Example 2 were evaluated by the methods described below. In addition, since the base material and the copper mesh peeled immediately after shaping | molding, the electroconductive sliding member of the comparative example 1 was not evaluated.

(Sliding property)
The slidability of each conductive member was measured by a thrust test apparatus shown in FIGS. 4A and 4B using a thrust tester AFT-6A (Toho Seimitsu Kogyo Co., Ltd.). The thrust testing apparatus is fixed to the square plate-shaped mating member Y1, three conductive sliding members Y2 disposed on the mating material Y1, and an upper surface of the conductive sliding member Y2. The pin Y3 and a jig (not shown) for applying a downward test surface pressure A to the conductive sliding member Y2 through the pin Y3. The three conductive sliding members Y2 are arranged point-symmetrically with respect to the center B of the upper surface of the counterpart material Y1, and the average distance between the center B and the center of the sliding surface of the conductive sliding member Y2 is 18 mm. It was.

Under the following conditions, the mating material Y1 was rotated in one direction with a virtual straight line connecting the center B of the upper surface and the center of the lower surface as the central axis, and the dynamic friction coefficient, the self wear amount, and the mating material wear amount were measured.
Counter member: 55 mm × 55 mm × 3 mm thick phosphor bronze (C5191) square plate Test surface pressure A: 0.25 MPa
Test speed: 2.64 m / sec (rotation speed: 2,000 rpm)
Environment: No lubrication Test time: 20h

[Self wear amount]
The difference before and after the test of the total average length d in the direction perpendicular to the sliding surfaces of the conductive sliding member Y2 and the pin Y3 measured with a micrometer was defined as the self-abrasion amount (μm / 20h) of the conductive sliding member Y2. . This self-abrasion amount is an average of the measured values of the three conductive sliding members Y2 and the pin Y3. The smaller the value of the self-wear amount, the better the slidability, and it can be judged that the case of 130 μm / 20 h or less is good and the case of exceeding 130 μm / 20 h is not good.

[Counterpart wear]
The mass of the mating material Y1 worn by measuring the difference in mass of the mating material Y1 before and after the test was determined. The mass of the worn counterpart Y1 was divided by the specific gravity of the counterpart Y1, and the worn volume was defined as the counterpart wear (mm ³ / 20h). Mating member wear amount, numerical indicate that excellent slidability the smaller, 0.5 mm ³ / 20h good for the following:, 0.5 mm ³ / 20h ultra 2.0 mm ³ / 20h somewhat better in the following cases can determine if the 2.0 mm ³ / 20h than not good.

(Dynamic friction coefficient)
The frictional force during rotation of the counterpart material Y1 was measured, and the value obtained by dividing the frictional force by the test surface pressure A was defined as the friction coefficient. The value obtained when 10 minutes passed from the start of rotation of the counterpart material Y1 and stabilized at a value lower than the friction coefficient (static friction coefficient) immediately after the start was defined as the dynamic friction coefficient. The dynamic friction coefficient indicates that the smaller the numerical value, the better the slidability, and it can be evaluated that the case of 0.15 or less is good and the case of 0.15 or more is not good.

(Conductivity)
In accordance with JIS-K7194 (1994) “Resistivity test method for conductive plastics by four-probe method”, the resistance value of the conductive sliding member was measured by the four-probe method to evaluate the conductivity. Specifically, as shown in FIG. 5, the terminal Z1 of a low resistivity meter (“Loresta-GP MCP-T600” manufactured by Mitsubishi Chemical Corporation) is brought into contact with the sliding surface of the conductive sliding member Z2, and the electrical resistance (× 10 ⁻³ Ω) was measured (N = 10 to 15). Note that the measurement was performed with care so that the four terminals Z1 are not in contact with only the base material Z4 and are not in contact with only the copper mesh Z3. Electrical resistance, numerical indicate that excellent conductivity smaller the, 2.5 × ^{10 -3 Ω} following cases good, 2.5 × ^{10 -3 Ω} than 10.0 × when less than ^{10 -3} Omega It can be judged that the case of slightly better than 10.0 × 10 ⁻³ Ω is not good.

  Table 1 shows the material of each conductive sliding member and the evaluation results described above. In Table 1, the mass parts of the phenol resin and the epoxy resin include the mass part of the curing agent used for curing. Further, “-” indicates that the corresponding material is not used.

  As is clear from Table 1, the conductive sliding members of Examples 1 to 4 were excellent in slidability and conductivity, and could suppress the peeling between the base material and the metal net. On the other hand, the conductive sliding member of Comparative Example 2 did not have a good self-abrasion amount. This is because the conductive sliding members of Examples 1 to 4 have a lower copper content that lowers the slidability than the conductive sliding member of Comparative Example 2, and instead improve the slidability. This is thought to be due to the high content of graphite. In addition, although the conductive sliding members of Examples 1 and 2 had a lower metal content than the conductive sliding member of Comparative Example 2, the electrical resistance was reduced. This is because the metal mesh provided in the conductive sliding members of Examples 1 and 2 is physically continuous in the direction in which the current flows, and therefore can efficiently conduct even a small amount compared to the metal powder. To be judged.

  Moreover, the electroconductive sliding member of the comparative example 1 was not able to suppress peeling with a base material and a metal net | network. It is judged that this is because the effect of suppressing the peeling between the base material and the metal net due to the entanglement of the carbon fiber with the metal net was not obtained.

  Furthermore, the conductive sliding member of Example 1 had less self-abrasion than the conductive sliding member of Example 2. This is presumably because the conductive sliding member of Example 1 was improved in strength by curing the phenolic resin by curing.

  Furthermore, the electric resistance of the conductive sliding member of Example 2 was lower than that of the conductive sliding member of Example 3. This is thought to be because pitch-based carbon fibers have a lower electrical resistivity than PAN-based carbon fibers. In addition, the conductive sliding member of Example 2 had lower self-abrasion amount and counterpart material abrasion amount than the conductive sliding member of Example 3. This is considered to be because a small amount of tar exudes from the pitch-based carbon fiber to the sliding surface due to heat generation during sliding, and as a result, the variation in the friction coefficient was stabilized. On the other hand, since the conductive sliding member of Example 3 did not achieve the effect of stabilizing the friction coefficient described above, it is considered that the amount of self wear and the amount of wear of the counterpart material increased due to vibration.

  Note that the self wear amount and the counterpart material wear amount are normally in a relationship in which one increases and the other decreases, but both may increase or decrease simultaneously due to factors such as the occurrence of vibration described above.

  Furthermore, the conductive sliding member of Example 2 had a lower self-abrasion amount and a counterpart material abrasion amount than the conductive sliding member of Example 4. This is considered to be because the phenol resin is more slidable than the epoxy resin.

  According to the conductive sliding member and the manufacturing method thereof, it is possible to provide a conductive sliding member that can suppress the peeling between the base material and the conductive layer and is excellent in slidability and conductivity. The alternator is excellent in power generation efficiency and has a long life.

DESCRIPTION OF SYMBOLS 1 Base material 2 Metal net 3 Net | network Y1 Opposite material Y2 Conductive sliding member Y3 Pin Z1 Terminal Z2 Conductive sliding member Z3 Base material Z4 Copper mesh

Claims (10)

A substrate containing carbon fibers and graphite in a matrix;
One or a plurality of conductive layers arranged in layers in this substrate, comprising metal as a main component and regularly having a plurality of openings penetrating the front and back,
The conductive layer is buried in the base material so that a material constituting the base material is filled in a plurality of openings,
A conductive sliding member in which end surfaces of the one or more conductive layers are exposed at least on a sliding surface.   The conductive sliding member according to claim 1, wherein the one or more conductive layers are disposed substantially perpendicular to the sliding surface.   The conductive sliding member according to claim 1, wherein the conductive layer is formed by disposing a wire in a stripe shape or a net shape.   The conductive sliding member according to claim 3, wherein the wire is disposed so as to be inclined with respect to the sliding surface.   The conductive sliding member according to any one of claims 1 to 4, wherein the plurality of conductive layers are disposed substantially in parallel and at substantially equal intervals.   The conductive sliding member according to any one of claims 1 to 5, wherein the metal is copper or a copper alloy.   The conductive sliding member according to any one of claims 1 to 6, wherein a main component of the matrix is a phenol resin.   The conductive sliding member according to any one of claims 1 to 7, wherein the carbon fiber is a pitch-based carbon fiber. A carbon brush including the conductive sliding member according to any one of claims 1 to 8,
An alternator used under conditions where the carbon brush is at 70 ° C. or higher. A substrate containing carbon fibers and graphite in a matrix;
A method for producing a conductive sliding member comprising: one or a plurality of conductive layers arranged in layers in the base material, the metal as a main component, and regularly having a plurality of openings penetrating the front and back,
A step of alternately laminating a plurality of substrate layers constituting the substrate and the one or more conductive layers;
And a step of thermocompression-bonding the laminate after the lamination step.

Images