US20040013879A1 - Carbon base member and process for producing the same - Google Patents
Carbon base member and process for producing the same Download PDFInfo
- Publication number
- US20040013879A1 US20040013879A1 US10/196,233 US19623302A US2004013879A1 US 20040013879 A1 US20040013879 A1 US 20040013879A1 US 19623302 A US19623302 A US 19623302A US 2004013879 A1 US2004013879 A1 US 2004013879A1
- Authority
- US
- United States
- Prior art keywords
- base member
- carbon
- carbon base
- iron
- carbon material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
- C04B41/50—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with inorganic materials
- C04B41/51—Metallising, e.g. infiltration of sintered ceramic preforms with molten metal
- C04B41/5144—Metallising, e.g. infiltration of sintered ceramic preforms with molten metal with a composition mainly composed of one or more of the metals of the iron group
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
- C04B41/81—Coating or impregnation
- C04B41/85—Coating or impregnation with inorganic materials
- C04B41/88—Metals
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
- C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
- C23C10/30—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes using a layer of powder or paste on the surface
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R39/00—Rotary current collectors, distributors or interrupters
- H01R39/02—Details for dynamo electric machines
- H01R39/04—Commutators
- H01R39/045—Commutators the commutators being made of carbon
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R43/00—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
- H01R43/06—Manufacture of commutators
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
- C04B2111/00844—Uses not provided for elsewhere in C04B2111/00 for electronic applications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
- Y10T428/252—Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/30—Self-sustaining carbon mass or layer with impregnant or other layer
Definitions
- the invention relates to a carbon base member that may be used in components such as the commutator segments of commutators in electric motors and a process for producing the carbon base member.
- the inside space of a housing constituting the fuel pump serves as a passage through which a fuel such as gasoline flows because the fuel pump itself is sunk (immersed) in the fuel.
- a fuel such as gasoline
- the materials used to fabricate the fuel pump are formed using materials that are not damaged by the corrosive action of the fuel.
- blended fuels containing a mixture of gasoline and alcohol or the like have become more widespread as a result of heightened interest in protecting the environment.
- the copper components fuel pumps for gasoline fuel can become corroded when used with these blended fuels.
- it is generally the commutator of a conventional electric motor, which is incorporated into a gasoline fuel pump, that is corroded by the alcohol.
- U.S. Pat. No. 5,175,463 describes the structure of a typical commutator segment.
- a commutator segment is made of carbon at the portion with which a brush slidably contacts the commutator segment (carbon material) to minimize the corrosion caused by alcohol.
- the commutator segment is formed with a metal layer on the surface (one surface of the carbon material) opposite to the portion that slidably contacts the brush.
- a conductive terminal member (riser bar) made of copper is integrated (electrical connection) with the metal layer.
- the carbon material is known to have poor surface wettability and is therefore difficult to bind with almost all metals.
- the surface of the carbon material is plated using nickel or the like and the conductive terminal member is bound to the plated surface by means of, for example, soldering.
- the metal layer formed by plating can be easily peeled off.
- the possibility that the plated metal layer, together with the conductive terminal member may peel from the surface of the carbon material.
- the strength of adhesion between the metal layer and the carbon material may be insufficient for a suitable commutator and results in inferior durability.
- JP-A-8-308183 shows a structure with a carbon base member, to which a conductive terminal member has been bound in advance, that is formed by unitedly sintering a carbon powder, a metal powder arranged layer-like to the carbon powder and the conductive terminal member arranged on the metal powder side.
- the sintering process is complicated and poses many difficulties.
- the sintering temperature must be carefully selected to be a temperature that is of the order at which the conductive terminal member made of copper is not deformed and lower than the melting point of the metal powder. This severely limits the range of temperatures that may be used to sinter the carbon material.
- the differences in the sintering shrinkage percentage between the metal powder and the carbon powder can lead to the formation of a clearance between them very easily. There is, therefore, a fear that the sintered metal and carbon layers may peel from each other.
- the invention provides a carbon base member comprising an iron layer formed on the surface thereof and bondable with a metal material.
- the carbon base member is formed by sticking an iron powder to a carbon material formed in advance by sintering, and by sintering the resulting product at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron.
- an inclined function material can be made in which the metal layer is securely formed on the surface of the carbon material unitedly.
- the invention provides a process for producing a carbon base member comprising an iron layer formed on the surface thereof and bondable with a metal material.
- the process comprises sticking an iron powder to a carbon material formed in advance by sintering, and thereafter sintering the resulting product at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron.
- the sintering temperature of the carbon material can be designed arbitrarily, so that the characteristics of the carbon base member can be selected in a free manner.
- an appropriate sintering temperature may be designed to be 1000 to 1300° C.
- the iron powder may be fine particles having an average particle diameter of 10 ⁇ m or less.
- the carbon base member may be used as a commutator segment constituting an electric motor.
- the surface of the carbon base member may be provided with a conductive terminal member bonded therewith.
- FIG. 1 is a sectional view for explaining a process for forming a carbon base member
- FIG. 2 is a microphotograph of a carbon base member
- FIG. 3 is a sectional view of a commutator.
- FIG. 1 shows a schematic view of the process for forming a carbon base member according to the present invention.
- the carbon material 1 is first prepared in advance. Namely the carbon material 1 is sintered, for example, by pressing or molding a carbon powder into a desired form (e.g., ring form), at 800 to 2000° C. for 2 hours and cooling the resulting product to normal temperature (ambient temperature).
- a desired form e.g., ring form
- the conditions under which the carbon material 1 is formed, such as the sintering temperature and sintering time, may be determined properly according to the use of the carbon material.
- An iron powder 2 a is stuck to the upper surface (front surface) of the carbon material 1 formed as described above.
- various methods taken to accomplish this such as a method in which the iron powder 2 a is directly placed in a proper amount on the upper surface of the carbon material 1 and is flattened with a spatula or the like.
- the iron powder 2 a may be forcibly stuck to the surface of the carbon material 1 by using a binder (e.g., an organic adhesive) that is, for instance, burned off in the heating stage during sintering so that it does not remain.
- the particle diameter of the iron powder 2 a to be used is about 5 to 15 ⁇ m and the average particle diameter is preferably 10 ⁇ m.
- the sintering temperature in this case is higher than the diffusion temperature of carbon (higher than diffusion temperature) and lower than the melting point of iron (lower than melting point), specifically 1000 to 1300° C. and preferably 1050 to 1150° C.
- the sintering time is 1 to 2 hours and preferably about 1.5 hours.
- the operation is preferably performed under a vacuum atmosphere. However, a vacuum atmosphere is not required in the present invention.
- FIG. 1(A) A mechanism of forming the iron layer 2 integrally on the surface of the carbon material 1 is assumed as follows. Specifically, in the aforementioned FIG. 1, the iron powder 2 a is placed uniformly on the surface of the carbon material 1 sintered in advance (FIG. 1(A)). When the carbon material 1 is heated to raise the temperature to above the diffusion temperature (about 800° C.) of carbon and lower than the melting point (1540° C.) of iron, the carbon diffuses and enters gaps present in the lattice point between iron atoms (Fe atoms). This causes a carburizing reaction which promotes the solid solution of carbon in iron (FIG. 1(B)).
- the carbon material 1 may be sintered in advance. Therefore, to state various conditions under which the carbon material 1 is sintered, the carbon material 1 may be processed by sintering in the condition so considered as to allow the carbon material 1 to be made into a product having characteristics according to a purpose of use. Unlike conventional carbon base members which are produced by sintering a carbon powder, a metal powder and a conductive terminal member simultaneously, it is unnecessary to adapt sintering conditions to materials other than the carbon material 1 . Thus, the claimed method imparts such an advantage that sintering conditions (e.g., temperature and pressure) and material properties of the carbon material 1 may be freely selected, depending on the desired characteristics of the carbon material 1 .
- sintering conditions e.g., temperature and pressure
- An iron powder having a particle diameter of 10 ⁇ m was placed on the surface of a carbon material, which had been sintered in advance at 1400° C. for 2 hours, in a layer having a uniform thickness of about 0.5 mm.
- the iron powder and carbon material were then sintered at about 1100° C. in a vacuum atmosphere for 1.5 hours to obtain a carbon base member.
- An electron microphotograph of this carbon base member is shown in FIG. 2.
- the thickness of the iron layer was about 200 ⁇ m in average.
- a separate analysis of the carbon base member confirmed that the iron layer was carburized.
- the surface of the iron layer of the carbon base member formed in this manner is thicker than that of a plated layer and is enough to solder a metal such as copper.
- a commutator segment which is a constituent of a commutator of a fuel pump disposed in a fuel tank containing alcohols, was actually formed.
- This segment was, as shown in FIG. 3, formed in a manner that the inside diameter side portions 4 a of plural risers 4 (conductive terminal members according to the present invention) were bound radially with the iron layer 2 of the carbon base member 3 in advance by means of soldering or the like.
- suitable bonding means include, but are not limited to, means such as brazing, fitting and adhering in addition to soldering.
- the commutator has a structure in which the U-riser bars 4 b are formed projecting from the outer peripheral side and a boss portion 5 is formed by molding an insulating resin material in the condition that the riser 4 is bound with the carbon base member 3 .
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Manufacturing & Machinery (AREA)
- Motor Or Generator Current Collectors (AREA)
- Ceramic Products (AREA)
- Manufacture Of Motors, Generators (AREA)
Abstract
An inclined function material is formed with an iron layer on a surface of a carbon material. This material can be used in a carbon base member and does not limit the choice of desired characteristics in a carbon base member. The process by which the carbon base member is formed also ensures the iron layer is integrated firmly with the surface of the carbon material. A suitable amount of an iron powder having a particle diameter of 5 to 15 μm is placed directly on the surface of a carbon material, which is sintered in advance under suitable conditions, and stuck to the surface uniformly and flatly. The iron powder and the carbon material are sintered at 1000° C. to 1300° C. and preferably 1050 to 1150° C. for 1 to 2 hours and preferably about 1.5 hours to form a carbon base member in which the iron layer is formed on one surface of the carbon base member.
Description
- 1. Field of Invention
- The invention relates to a carbon base member that may be used in components such as the commutator segments of commutators in electric motors and a process for producing the carbon base member.
- 2. Description of Related Art
- In general, in an in-tank type fuel pump mounted on vehicles, the inside space of a housing constituting the fuel pump serves as a passage through which a fuel such as gasoline flows because the fuel pump itself is sunk (immersed) in the fuel. In such a system, it is necessary that the materials used to fabricate the fuel pump are formed using materials that are not damaged by the corrosive action of the fuel.
- Recently, blended fuels containing a mixture of gasoline and alcohol or the like have become more widespread as a result of heightened interest in protecting the environment. However, it is known that the copper components fuel pumps for gasoline fuel can become corroded when used with these blended fuels. In particular, it is generally the commutator of a conventional electric motor, which is incorporated into a gasoline fuel pump, that is corroded by the alcohol.
- U.S. Pat. No. 5,175,463 describes the structure of a typical commutator segment. Generally, a commutator segment is made of carbon at the portion with which a brush slidably contacts the commutator segment (carbon material) to minimize the corrosion caused by alcohol. The commutator segment is formed with a metal layer on the surface (one surface of the carbon material) opposite to the portion that slidably contacts the brush. A conductive terminal member (riser bar) made of copper is integrated (electrical connection) with the metal layer. However, the carbon material is known to have poor surface wettability and is therefore difficult to bind with almost all metals. In order to bind the conductive terminal member with the surface of the carbon material, it is necessary to form a metal layer between them. For this, according to the aforementioned patent, the surface of the carbon material is plated using nickel or the like and the conductive terminal member is bound to the plated surface by means of, for example, soldering. In this case, the metal layer formed by plating can be easily peeled off. Thus, even if integrated bonding between the metal layer and the conductive terminal member could be accomplished, the possibility that the plated metal layer, together with the conductive terminal member, may peel from the surface of the carbon material. The strength of adhesion between the metal layer and the carbon material may be insufficient for a suitable commutator and results in inferior durability.
- In addition, JP-A-8-308183 shows a structure with a carbon base member, to which a conductive terminal member has been bound in advance, that is formed by unitedly sintering a carbon powder, a metal powder arranged layer-like to the carbon powder and the conductive terminal member arranged on the metal powder side.
- However, because this is a configuration in which a carbon powder, a metal powder and a conductive terminal member are sintered integrally, the sintering process is complicated and poses many difficulties. For example, the sintering temperature must be carefully selected to be a temperature that is of the order at which the conductive terminal member made of copper is not deformed and lower than the melting point of the metal powder. This severely limits the range of temperatures that may be used to sinter the carbon material. Furthermore, when sintering these different materials together, the differences in the sintering shrinkage percentage between the metal powder and the carbon powder can lead to the formation of a clearance between them very easily. There is, therefore, a fear that the sintered metal and carbon layers may peel from each other. In order to prevent this, it is necessary to select a carbon material that has a sintering shrinkage percentage that is similar to that of the metal powder. However, this solution to prevent peeling then limits types of carbon material that may be selected, which excludes the use of certain carbon materials having the desired characteristics for a particular application. The problem to be solved by the present invention consists in this point.
- In view of the above problems, the invention has been made for the purpose of solving these problems. In one embodiment, the invention provides a carbon base member comprising an iron layer formed on the surface thereof and bondable with a metal material. The carbon base member is formed by sticking an iron powder to a carbon material formed in advance by sintering, and by sintering the resulting product at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron. According to the invention, an inclined function material can be made in which the metal layer is securely formed on the surface of the carbon material unitedly.
- Further, the invention provides a process for producing a carbon base member comprising an iron layer formed on the surface thereof and bondable with a metal material. The process comprises sticking an iron powder to a carbon material formed in advance by sintering, and thereafter sintering the resulting product at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron.
- According to this process, the sintering temperature of the carbon material can be designed arbitrarily, so that the characteristics of the carbon base member can be selected in a free manner.
- In the invention, an appropriate sintering temperature may be designed to be 1000 to 1300° C.
- Further, in the invention, the iron powder may be fine particles having an average particle diameter of 10 μm or less.
- Also, in the invention, the carbon base member may be used as a commutator segment constituting an electric motor.
- Moreover, in the invention, the surface of the carbon base member may be provided with a conductive terminal member bonded therewith.
- FIG. 1 is a sectional view for explaining a process for forming a carbon base member;
- FIG. 2 is a microphotograph of a carbon base member; and
- FIG. 3 is a sectional view of a commutator.
- It is generally known that when iron with a small carbon content is heated at a temperature of about 800° C. or more, which exceeds the solid-solution temperature of carbon in a carbon atmosphere, a so-called “carburization” reaction in which carbon is diffused to the surface of an iron material takes place. This gradually increases the content of carbon. It is also known that iron or an iron-base material in which carbon is dissolved in the form of a solid solution has a lower melting point. Generally, the melting point decreases as carbon content increases. Furthermore, it is also known that the iron or iron-base materials melted by the above carburizing reaction are highly reactive.
- From the fact as mentioned above, it is assumed that a solid solution corresponding to a carburizing reaction is produced on the carbon base member to form an iron layer by heating to a temperature above the solid solution temperature of carbon when an iron powder is placed on the surface of the carbon material, which has been sintered in advance, and the foregoing formation process has been invented on this assumption.
- FIG. 1 shows a schematic view of the process for forming a carbon base member according to the present invention.
- The
carbon material 1 is first prepared in advance. Namely thecarbon material 1 is sintered, for example, by pressing or molding a carbon powder into a desired form (e.g., ring form), at 800 to 2000° C. for 2 hours and cooling the resulting product to normal temperature (ambient temperature). The conditions under which thecarbon material 1 is formed, such as the sintering temperature and sintering time, may be determined properly according to the use of the carbon material. - An
iron powder 2 a is stuck to the upper surface (front surface) of thecarbon material 1 formed as described above. There are various methods taken to accomplish this, such as a method in which theiron powder 2 a is directly placed in a proper amount on the upper surface of thecarbon material 1 and is flattened with a spatula or the like. Also, theiron powder 2 a may be forcibly stuck to the surface of thecarbon material 1 by using a binder (e.g., an organic adhesive) that is, for instance, burned off in the heating stage during sintering so that it does not remain. In addition, the particle diameter of theiron powder 2 a to be used is about 5 to 15 μm and the average particle diameter is preferably 10 μm. - The sintering temperature in this case is higher than the diffusion temperature of carbon (higher than diffusion temperature) and lower than the melting point of iron (lower than melting point), specifically 1000 to 1300° C. and preferably 1050 to 1150° C. The sintering time is 1 to 2 hours and preferably about 1.5 hours. As to the sintering atmosphere, the operation is preferably performed under a vacuum atmosphere. However, a vacuum atmosphere is not required in the present invention. These operational conditions enables the formation of a
carbon base member 3 provided with aniron layer 2 formed on the surface thereof and thecarbon base member 3 may be used in various uses as a so-called inclined function material. - A mechanism of forming the
iron layer 2 integrally on the surface of thecarbon material 1 is assumed as follows. Specifically, in the aforementioned FIG. 1, theiron powder 2 a is placed uniformly on the surface of thecarbon material 1 sintered in advance (FIG. 1(A)). When thecarbon material 1 is heated to raise the temperature to above the diffusion temperature (about 800° C.) of carbon and lower than the melting point (1540° C.) of iron, the carbon diffuses and enters gaps present in the lattice point between iron atoms (Fe atoms). This causes a carburizing reaction which promotes the solid solution of carbon in iron (FIG. 1(B)). Along with the progress of this solid solution and hence an increase in the amount of the solid solution of carbon, the melting point of the solid solution falls, whereby the above solid solution produced at the contact portion between thecarbon material 1 and theiron powder 2 a melts. This melted solid solution flows into fine porous surfaces formed on the surface of thecarbon material 1 and firmly adheres to the porous surface (FIG. 1(C)). By an anchor effect produced by the adhesion, it is assumed that an inclined function material put in the condition that theiron layer 2 is firmly integrated with the surface of thecarbon material 1 is made. - When forming the
carbon base member 3 provided with theiron layer 2 on the surface thereof in this manner, generally thecarbon material 1 may be sintered in advance. Therefore, to state various conditions under which thecarbon material 1 is sintered, thecarbon material 1 may be processed by sintering in the condition so considered as to allow thecarbon material 1 to be made into a product having characteristics according to a purpose of use. Unlike conventional carbon base members which are produced by sintering a carbon powder, a metal powder and a conductive terminal member simultaneously, it is unnecessary to adapt sintering conditions to materials other than thecarbon material 1. Thus, the claimed method imparts such an advantage that sintering conditions (e.g., temperature and pressure) and material properties of thecarbon material 1 may be freely selected, depending on the desired characteristics of thecarbon material 1. - Experimental examples will be shown below.
- An iron powder having a particle diameter of 10 μm was placed on the surface of a carbon material, which had been sintered in advance at 1400° C. for 2 hours, in a layer having a uniform thickness of about 0.5 mm. The iron powder and carbon material were then sintered at about 1100° C. in a vacuum atmosphere for 1.5 hours to obtain a carbon base member. An electron microphotograph of this carbon base member is shown in FIG. 2. The thickness of the iron layer was about 200 μm in average. A separate analysis of the carbon base member confirmed that the iron layer was carburized.
- The surface of the iron layer of the carbon base member formed in this manner is thicker than that of a plated layer and is enough to solder a metal such as copper. Then, using the carbon base member, a commutator segment, which is a constituent of a commutator of a fuel pump disposed in a fuel tank containing alcohols, was actually formed. This segment was, as shown in FIG. 3, formed in a manner that the inside
diameter side portions 4 a of plural risers 4 (conductive terminal members according to the present invention) were bound radially with theiron layer 2 of thecarbon base member 3 in advance by means of soldering or the like. In this segment, it was confirmed that the joining of the riser 4 with theiron layer 2 was made firmly and the segment attained a function as a commutator sufficiently. In this case, examples of suitable bonding means include, but are not limited to, means such as brazing, fitting and adhering in addition to soldering. - It is to be noted that the commutator has a structure in which the U-riser bars4 b are formed projecting from the outer peripheral side and a
boss portion 5 is formed by molding an insulating resin material in the condition that the riser 4 is bound with thecarbon base member 3.
Claims (14)
1. A carbon base member, comprising:
a sintered carbon material; and
an iron layer, bondable with a metal material, formed on a surface of the sintered carbon material, wherein the carbon base member layer is formed by sticking an iron powder to a surface of the sintered carbon material and sintering the iron powder and sintered carbon material at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron.
2. The carbon base member according to claim 1 , wherein the temperature of sintering the iron powder and sintered carbon material is 1000 to 1300° C.
3. The carbon base member according to claim 1 , wherein the iron powder comprises fine particles having an average particle diameter of 10 μm or less.
4. The carbon base member according to claim 1 , wherein the carbon base member is used as a commutator segment constituting an electric motor.
5. The carbon base member according to claim 4 , wherein the commutator segment further comprises a conductive terminal member bound to the surface of the carbon base member.
6. A process for producing a carbon base member having an iron layer formed on a surface of the carbon base member, wherein the iron layer is bondable with a metal material, the process comprising:
a first sintering of a carbon material;
sticking an iron powder to a surface of the sintered carbon material ; and
a second sintering of the iron powder and the sintered carbon material at a temperature higher than the diffusion temperature of carbon and lower than the melting point of iron.
7. The process for producing a carbon base member according to claim 6 , wherein the temperature of the second sintering is 1000 to 1300° C.
8. The process for producing a carbon base member according to claim 6 , wherein the iron powder is fine particles having an average particle diameter of 10 μm or less.
9. The process for producing a carbon base member according to claim 6 , wherein the carbon base member is used as a commutator segment constituting an electric motor.
10. The process for producing a carbon base member according to claim 9 , wherein the commutator segment is obtained by binding a conductive terminal member with the surface of the carbon base member.
11. The process for producing a carbon base member according to claim 7 , wherein the carbon base member is used as a commutator segment constituting an electric motor.
12. The process for producing a carbon base member according to claim 11 , wherein the commutator segment is obtained by binding a conductive terminal member with the surface of the carbon base member.
13. The process for producing a carbon base member according to claim 8 , wherein the carbon base member is used as a commutator segment constituting an electric motor.
14. The process for producing a carbon base member according to claim 13 , wherein the commutator segment is obtained by binding a conductive terminal member with the surface of the carbon base member.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001140147A JP4718718B2 (en) | 2001-05-10 | 2001-05-10 | Carbon substrate manufacturing method |
US10/196,233 US6682693B1 (en) | 2001-05-10 | 2002-07-17 | Carbon base member and process for producing the same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001140147A JP4718718B2 (en) | 2001-05-10 | 2001-05-10 | Carbon substrate manufacturing method |
US10/196,233 US6682693B1 (en) | 2001-05-10 | 2002-07-17 | Carbon base member and process for producing the same |
Publications (2)
Publication Number | Publication Date |
---|---|
US20040013879A1 true US20040013879A1 (en) | 2004-01-22 |
US6682693B1 US6682693B1 (en) | 2004-01-27 |
Family
ID=32300119
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/196,233 Expired - Lifetime US6682693B1 (en) | 2001-05-10 | 2002-07-17 | Carbon base member and process for producing the same |
Country Status (2)
Country | Link |
---|---|
US (1) | US6682693B1 (en) |
JP (1) | JP4718718B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090011242A1 (en) * | 2006-03-06 | 2009-01-08 | Mitsuba Corporation | Carbon Commutator and Process for Producing the Same |
CN102201637A (en) * | 2010-03-26 | 2011-09-28 | 德昌电机(深圳)有限公司 | Commutator and manufacturing method thereof |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2145892A (en) * | 1983-08-31 | 1985-04-03 | Philips Electronic Associated | Surface acoustic wave device |
US5175463A (en) * | 1989-08-07 | 1992-12-29 | Kirkwood Industries | Carbon commutator |
JP2565411B2 (en) * | 1990-03-14 | 1996-12-18 | 富士写真フイルム株式会社 | Coating device |
JP3179812B2 (en) * | 1991-09-17 | 2001-06-25 | トーカロ株式会社 | Carbon member having metal spray coating layer with excellent adhesion |
JPH0881290A (en) * | 1994-09-09 | 1996-03-26 | Hitachi Chem Co Ltd | Copper alloy-coated carbon material and its production and plasma counter material using copper alloy-coated carbon material |
JP3360092B2 (en) | 1995-05-01 | 2002-12-24 | 株式会社南信精機製作所 | Carbon commutator |
JPH0946978A (en) * | 1995-07-28 | 1997-02-14 | Mitsuba Corp | Commutator and its manufacture |
US6222298B1 (en) * | 1997-06-08 | 2001-04-24 | Mitsuba Corporation | Carbon commutator and method for producing the same |
JP2000023425A (en) * | 1998-06-30 | 2000-01-21 | Denso Corp | Carbon structure and its manufacture |
JP3805912B2 (en) * | 1998-11-13 | 2006-08-09 | トライス株式会社 | Carbon commutator |
JP4376362B2 (en) * | 1999-07-29 | 2009-12-02 | 株式会社ミツバ | Carbon commutator manufacturing method |
JP2004208398A (en) * | 2002-12-25 | 2004-07-22 | Mitsuba Corp | Carbon substrate and manufacturing method thereof, and commutator |
JP2005041736A (en) * | 2003-07-23 | 2005-02-17 | Mitsuba Corp | Carbon base material and method of manufacturing the same |
-
2001
- 2001-05-10 JP JP2001140147A patent/JP4718718B2/en not_active Expired - Lifetime
-
2002
- 2002-07-17 US US10/196,233 patent/US6682693B1/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090011242A1 (en) * | 2006-03-06 | 2009-01-08 | Mitsuba Corporation | Carbon Commutator and Process for Producing the Same |
US7799430B2 (en) | 2006-03-06 | 2010-09-21 | Mitsuba Corporation | Carbon commutator and process for producing the same |
CN102201637A (en) * | 2010-03-26 | 2011-09-28 | 德昌电机(深圳)有限公司 | Commutator and manufacturing method thereof |
Also Published As
Publication number | Publication date |
---|---|
JP4718718B2 (en) | 2011-07-06 |
US6682693B1 (en) | 2004-01-27 |
JP2002338378A (en) | 2002-11-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8303854B2 (en) | Sintering silver paste material and method for bonding semiconductor chip | |
CN1273993C (en) | Conductive paste, conductive structure using the same, electronic part, module, circuit board, method for electrical connection, method for manufacturing circuit board, and ceramic electronic part | |
US11338397B2 (en) | Soldering material for active soldering and method for active soldering | |
US8900021B2 (en) | Electrical contact terminal with improved connection portion | |
US6674212B2 (en) | Current-carrying member for a direct-current motor in a fuel pump, method for producing the same, and fuel pump | |
CA2289419C (en) | Carbon commutator | |
JPH029155A (en) | Composite metal material | |
JP4136648B2 (en) | Dissimilar material joined body and manufacturing method thereof | |
US8878417B2 (en) | Commutator | |
JP5014326B2 (en) | Carbon commutator and manufacturing method thereof | |
US7638721B2 (en) | Contact surfaces for electrical contacts | |
JP3425962B2 (en) | Commutator with improved segment joinability | |
US6682693B1 (en) | Carbon base member and process for producing the same | |
JP2003212670A (en) | Joined product of different kinds of materials and its manufacturing process | |
US20130216847A1 (en) | Starting material for a sintered bond and process for producing the sintered bond | |
JP2007515146A (en) | Carbon brush, carbon brush manufacturing method, and material used for carbon brush | |
JP2006253343A (en) | Thermoelectric element integrating electrode, and its manufacturing process | |
JP2011006760A (en) | Method for producing copper alloy strip | |
JP2004208398A (en) | Carbon substrate and manufacturing method thereof, and commutator | |
JP4600744B2 (en) | Manufacturing method of carbon commutator | |
CN216738577U (en) | Ceramic substrate surface multilayer composite coating structure | |
US6123252A (en) | Process for fixing a graphite-rich material onto a metallic body | |
JPH0259562B2 (en) | ||
JP2002134361A (en) | Solid electrolytic capacitor and its manufacturing method | |
JP2007177330A (en) | Plated material, method of producing the same, and electrical/electronic parts using the same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: MITSUBA CORPORATION, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:TANAKA, YOSHIHIRO;ISHIZAKI, MITSUNARI;KURIBARA, MOTOAKI;REEL/FRAME:013185/0565 Effective date: 20020731 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
FPAY | Fee payment |
Year of fee payment: 12 |