Classifications

• • 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
  • H01R43/12—Manufacture of brushes
• • 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
  • H01R39/18—Contacts for co-operation with commutator or slip-ring, e.g. contact brush
  • H01R39/20—Contacts for co-operation with commutator or slip-ring, e.g. contact brush characterised by the material thereof
  • H01R39/22—Contacts for co-operation with commutator or slip-ring, e.g. contact brush characterised by the material thereof incorporating lubricating or polishing ingredient
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K13/00—Structural associations of current collectors with motors or generators, e.g. brush mounting plates or connections to windings; Disposition of current collectors in motors or generators; Arrangements for improving commutation
  • H02K13/10—Arrangements of brushes or commutators specially adapted for improving commutation

Definitions

• the invention relates to an electrical machine, in particular a commutator machine according to the preamble of patent claim 1.
• Mechanically commutating commutator machines are often used in motor vehicles.
• high-performance direct-current motors are used to start internal combustion engines in vehicles.
• the current passes through one or more pairs of brushes on a commutator and from there into the armature winding of the machine.
• the so-called carbon brushes usually consist of a sintered material, which mainly contains copper and graphite components. These carbon brushes and the commutator are subject to wear during operation.
• starters are typically for a short-term operation with 30 000 to 60 000
• the carbon brushes are mixed with a certain amount of cleaning agents as an additive. That provides for a degree of constant
• the wear behavior of the carbon brushes must be optimized by the best possible coordination of lubrication and cleaning of the commutator. It is known to provide the carbon brushes with at least two layer sections that extend beyond the height and width of the carbon brushes away to their tread. A layer section is provided to improve the Stromkommut réelle with a higher graphite content and another layer section as a power layer for power management with a higher copper content. Furthermore, it has already been proposed that the carbon brushes have a cleaning agent section in at least one of the aforementioned layer section whose cleaning agent content is higher than in the other
• Layer portion of carbon brushes is. Since all carbon brushes of the DC motor are also constructed the same, the effect of the various admixtures adds up accordingly. Therefore, the various parameters such as wear, lubrication, commutation and the like can only be set relatively coarse.
• the present solution seeks to set one or more of the aforementioned parameters on the carbon brushes much more accurately.
• the machine according to the invention with the characterizing features of claim 1 has the advantage that the additive is no longer evenly distributed in all carbon brushes for a parameter acting on the entire commutator parameters such as lubrication or cleaning, but in only one carbon brush or only in a few carbon brushes
• an optimization of the fine tuning for setting a carbon brush parameter is achieved in that the proportion of the additive in the at least one carbon brush is relatively at least 10 percent higher than in the other carbon brushes.
• the differing proportion of the additive is introduced only in one layer section of the carbon brush, all carbon brushes of the machine having two or more layers.
• the layer section advantageously extends over the height and width of the carbon brush to its tread.
• the additive is a cleaning agent for cleaning the
• Pigtail out changed preferably increases as Putzstoff- share.
• at least one of the carbon brushes of the machine is provided with a portion of a further additive deviating significantly from the remaining carbon brushes.
• the further additive is a lubricant.
• it is optimized - A -
• Parameter setting advantageous if one or a part of the carbon brushes a higher proportion of an additive, preferably a cleaning agent, and another or another part of the carbon brushes has a higher proportion of the second additive, preferably a lubricant.
• an additive preferably a cleaning agent
• another or another part of the carbon brushes has a higher proportion of the second additive, preferably a lubricant.
• FIG. 1 shows a commutator motor in cross-section in the commutator region
• FIGS. 2a and 2b show a carbon brush with and without an additive
• Figure 3 a and 3b show a carbon brush with two layer sections without and with
• FIG. 4 shows the four carbon brushes of an engine with an additive in one
• FIG. 5 shows four carbon brushes of an engine with a first additive in a first
• Carbon brush and a second additive in a second carbon brush and Figure 6 shows an alternative embodiment for a motor with six carbon brushes.
• a starter motor is denoted by 10, which is shown as a commutator in its cross section at the commutator end.
• the starter motor 10 is used for cranking internal combustion engines in motor vehicles, which are equipped for example with a start-stop system. He has a pole housing 11 that has six unrecognizable, permanent magnetic poles on its inner circumference, which interact with a runner, not shown.
• a commutator 13 At the rear end of the rotor carries on its rotor shaft 12, a commutator 13 for powering the rotor windings.
• the commutator 13 is provided at its periphery with fins 20 which cooperate with four carbon brushes 14.
• the carbon brushes 14 are each received with a brush spring 15 in a brush holder 16 axially displaceable and pressed with its tread 21 against the commutator.
• the four brush holders are accommodated on a brush plate 17, which in turn is attached to the front end of the starter motor 10 and over the pole housing 11 to ground.
• the carbon brushes 14 are each provided at their rear portion with a pigtail 18.
• the carbon brushes 14 form two plus and two minus carbon brushes.
• the two plus carbon brushes 14 are contacted via their pigtails 18 with a plus terminal 19 and the minus carbon brushes are welded via their connecting leads 18 to a metal strip 17 a of the brush plate 17 and are thus grounded.
• three of the four carbon brushes 14 have an identical material composition throughout. They consist of a sintered material that mainly contains copper and graphite components. In this case, copper serves for better electrical conductivity and graphite serves for better commutation at the commutator lamellae 20.
• FIG. 2a shows one of these three brushes.
• the brush material also contains other additives such as cleaning agents and
• Lubricants in low concentration This material composition of the three carbon brushes 14 is denoted by A 'in FIG. 2a.
• the lubricants in the carbon brushes 14 form a lubricating film on the surface of the commutator 13, which reduces the mechanical abrasion of the carbon brushes 14. Nevertheless, the commutator surface is increasingly contaminated by the abraded brush material unless it is cleaned continuously or at intervals. With a higher proportion of cleaning agent in all carbon brushes 14, however, the brush abrasion would be enhanced, and thus reduces the life of the carbon brushes 14.
• FIG. 2b shows the carbon brush 14a with the other material composition A'a. While the proportion of cleaning agent in the material A 'of the three carbon brushes according to FIG. 2a is about 0.5%, it is significantly increased in the material A'a of the fourth carbon brush 14a according to FIG. 2b at 0.7%.
• the carbon brushes 14 are in a known manner in the direction of rotation of the commutator 13 in two layer sections A. and B divided.
• the accumulating first layer section A is here provided with an increased copper content for better current conduction and the second, running layer section B contains a higher graphite content for optimal commutation.
• the material in the layer section A is also with a small proportion of a cleaning agent and the material of the layer section B is with a small proportion of a
• the fourth carbon brush 14a is changed in such a way that in its first layer section Aa of FIG
• Cleaning agent content compared to the other carbon brushes 14 is significantly increased and that in the second layer section Bb, the lubricant content compared to the other carbon brushes 14 is significantly increased.
• a first additive is contained in the first layer section and a second additive in a significantly higher concentration in the second layer section than in the remaining carbon brushes 14.
• FIG. 4 likewise shows four carbon brushes 14, each having two layer sections A and B for a starter motor according to FIG. 1, in a third exemplary embodiment. While the material composition in the layer sections B of all brushes is the same, only in the layer section Aa of the fourth carbon brush 14a is the proportion of cleaning agent significantly higher than that of the layer sections A of the remaining carbon brushes 14.
• Carbon brushes 14 a same material composition In this case, the carbon brush 14a has an increased proportion of cleaning agent in its layer section Aa, and the carbon brush 14b has an increased lubricant proportion only in the layer section Bb.
• the carbon brushes 14 become shorter and shorter with increasing service life due to wear, their contact pressure on the commutator 13 steadily decreases due to the longer spring travel of the brush springs 15.
• the carbon brush 14a of the cleaning agent content in the layer section Aa of the tread 21 of the carbon brush to the pigtail out In order to ensure a sufficient cleaning of the commutator even then, takes on the carbon brush 14a of the cleaning agent content in the layer section Aa of the tread 21 of the carbon brush to the pigtail out.
• the plus and minus carbon brushes 14 are each offset by 60 ° to each other. This leaves an angle of 120 ° between the two plus brushes and the two minus brushes. In powerful six-pole machines, however, six carbon brushes 14 are used, which are offset by 60 ° to each other. Again, the solution according to the invention can be used advantageously.
• FIG. 6 shows, as a further exemplary embodiment, the six carbon brushes of such a machine with two each
• Layer sections A and B While four of these six carbon brushes 14 are the same in their composition of matter, the two remaining carbon brushes 14a have a different composition of matter. Thus, in the layer section Aa of the two carbon brushes 14a an increased proportion of cleaning agent and in the layer section Bb each introduced an increased proportion of lubricant. The fine adjustment of the parameters cleaning and sliding takes place here via two carbon brushes 14a.
• this solution can also be transferred to an electric machine with four carbon brushes, which is particularly advantageous when the two plus carbon brushes have different direction of rotation-dependent commutation behavior compared to the minus carbon brushes. In addition to a fine adjustment can thus be compensated in this way even commutation differences.
• a first portion 14a of the carbon brushes 14 is expediently provided with a higher proportion of one additive and a further portion 14b of the carbon brushes 14 with a higher proportion of another additive.
• the carbon brushes 14 may also be provided with a third layer section C, as shown by dashed lines on the left carbon brush 14 in FIG.
• This layer C may contain other additives or no additives.
• the invention is not limited to the illustrated embodiments.
• brushes with several layer sections in the selected carbon brushes 14a, 14b to introduce an additive in both layer sections Aa and Bb of the carbon brush 14a with an increased proportion.
• a cleaning agent usually natural ash or alumina are used.
• a lubricant e.g. Molypdehyde sulfide used.
• the invention is also applicable not only to starter motors for motor vehicles to achieve a longer life, but also good at commutator for other applications.

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• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Power Engineering (AREA)
• Motor Or Generator Current Collectors (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=41130425

Family Applications (1)

Country Status (6)

Families Citing this family (7)

Family Cites Families (30)

• 2008
  • 2008-05-09 DE DE200810001702 patent/DE102008001702A1/de not_active Withdrawn
• 2009
  • 2009-05-07 EP EP09742115A patent/EP2277255A2/de not_active Withdrawn
  • 2009-05-07 JP JP2011507923A patent/JP5669727B2/ja not_active Expired - Fee Related
  • 2009-05-07 KR KR1020107025171A patent/KR20110021762A/ko not_active Withdrawn
  • 2009-05-07 US US12/991,810 patent/US8917008B2/en not_active Expired - Fee Related
  • 2009-05-07 WO PCT/EP2009/055522 patent/WO2009135897A2/de not_active Ceased

Non-Patent Citations (1)

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