Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K5/00—Casings; Enclosures; Supports
  • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
  • H02K5/14—Means for supporting or protecting brushes or brush holders
  • H02K5/143—Means for supporting or protecting brushes or brush holders for cooperation with commutators
  • H02K5/145—Fixedly supported brushes or brush holders, e.g. leaf or leaf-mounted 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
  • H01R39/38—Brush holders
  • H01R39/381—Brush holders characterised by the application of pressure to brush
• • 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
  • H01R39/38—Brush holders
  • H01R39/39—Brush holders wherein the brush is fixedly mounted in the holder

Definitions

• the invention relates to a holding element for a commutator sliding contact of an electric motor according to the preamble of claim 1 and to an electric motor according to claim 12.
• hammer brushes in which a KommutatorschleifCount (carbon brush) is held on a spiral spring and is spring-loaded by this in the radial direction on a commutator.
• the bending spring is clamped with its remote from the sliding contact end in a carrier part (brush holder).
• the bending spring arise in a deflection inhomogeneous fiber tension, which brings with it the risk of damage to the spiral spring in the region of the clamping by plastic deformation.
• the invention has for its object to propose a holding element for a KommutatorschleifCount, in which the risk of damage is minimized by overbending. Furthermore, the object is to propose an electric motor with a correspondingly optimized holding element.
• the invention is based on the idea of designing the spring section of the retaining element in such a way that the edge fiber stresses of the spring section are at least approximately constant in at least one section of the spring section.
• Preferred is a design of the spring Section, in which the edge fiber stresses are not only constant in a section of the spring portion in the longitudinal direction, but along the entire longitudinal extent of the spring portion.
• the spring section according to the invention is designed such that both the tensile stresses in the region of the largest bending radius and the compressive stresses in the region of the smallest bending radius in the longitudinal direction of at least one section, the flat, plate-shaped, spring section considered are constant.
• the fiber stresses are viewed transversely to the longitudinal extent and at least approximately zero in the region of a neutral fiber.
• An at least approximately constant edge-fiber stress iS of the invention is understood to mean a fiber tension which is essentially constant at every position in the longitudinal direction, ie deviates less than 10% from a fiber tension centered in the longitudinal direction. Preferably, the deviation is less than 5%, more preferably less than 1%.
• Particularly preferred is an embodiment of the spring portion of the holding element, wherein the spring portion, at least a portion of the spring portion, even then has constant Randfaserhard in the longitudinal direction, if the spring portion, for example, for mounting an axle-fixed ball bearing beyond the normal Vortheseshus radially stretched on the outside, that is overstretched.
• a designed according to the concept of the invention retaining element with a spring portion formed as described has significant advantages over known holding elements.
• edge fiber tension is to be immediately adjacent to a fastening section with which the retaining element is fixed in a carrier part, at least approximately, preferably being exactly constant.
• An attachment of the holding element preferably takes place by clamping into a carrier part (brush carrier).
• a width extension formed from solid material is understood to be the width extension completed by solid material, preferably a constant thickness extension, i. the width extension formed by solid material takes into account any recesses provided in the spring section, in particular breakthroughs.
• Io is the length of the subsection with a constant edge fiber tension or the entire length of the spring section if the edge fiber tension is to be constant over the entire longitudinal extension of the spring section.
• the constant bo is the width extension of the partial section or of the entire spring section formed by solid material at an end facing away from the sliding contact, ie in a region immediately adjacent to a clamped region of the spring section or directly to a fastening section of the retaining element.
• the value bo is thus that of solid material, i. Width taken along the longitudinal direction furthest away from the grinding contact, without the consideration of recesses, of the region of the spring section.
• the variable x is a longitudinal extension coordinate and describes any position along the longitudinal extension of the subsection or the entire spring section.
• the spring section or the partial section of the spring section is formed exclusively of solid material, an above-mentioned subordinate section will taper or spring section in the longitudinal direction to the holding portion, ie its width extension decreases seen in the longitudinal direction, preferably linearly from.
• Particularly preferred is a symmetrical design of the spring section or of the partial section with respect to a longitudinal central axis (symmetry axis) of the partial section or of the spring section.
• the actual width of the partial section and / or of the spring section is at least approximately constant in the longitudinal direction.
• This can be realized, for example, by broadening a preferably symmetrical inner recess in the longitudinal direction towards the commutator sliding contact.
• Particularly preferred is an embodiment in which the recess, in particular symmetrically widened in a triangular or trapezoidal manner towards the commutator grinding contact, in particular such that the solid material formed by The width extension adjacent to the recess obeys the previously described formula.
• a holding section holding the commutator contact in particular clamping, has a rigid, ie. non-resilient ground plane.
• this ground plane or footprint is instantaneous, i. seamless over into the spring portion of the holding element.
• the spring section merges at its end facing away from the KommutatorschleifCount end in a mounting portion with which the holding element is fixed in an electric motor, in particular in a support member (brush holder).
• the attachment portion is equipped with a latching geometry and / or a lug geometry to allow a defined setting of the holding element in the, preferably made of thermoplastic material, carrier part.
• the retaining element can be clamped with its attachment portion in the support part and / or embossed by energy input in the form of heat or ultrasound at the attachment point. An undercut formed in this way prevents slipping out of the retaining element from its mounting position.
• the invention also leads to an electric motor with a rotatably connected to an armature shaft commutator to which at least one KommutatorschleifCount rests, in a holding element formed according to the concept of the invention is held.
• the electric motor preferably has an armature shaft-fixed ball bearing, in which the mounting is axially pushed axially through a carrier part having a plurality of holding elements each having a commutator grinding contact, during which the holding elements are overstretched.
• 1 is a side view of a prestressed holding element
• FIG. 2 is a perspective view of the holding element ge ⁇ according to FIG. 1,
• Fig. 3 federkraftbeierhal a section of an electric motor, in which sev- eral holding elements are arranged in a plastic support part and each have a Kommuta ⁇ torschleif toast a commutator in a radial inward direction, and
• Fig. 4 shows an alternative embodiment of a holding ⁇ element in which the spring portion seen in the longitudinal ⁇ extension has a constant overall width.
• a holding element 1 for a KommutatorschleifCount 2 shown in Fig. 3 is shown.
• the commutator sliding contact 2 is spring-loaded in the radial direction inwardly on a rotatably arranged commutator 3 of an electric motor 4.
• the holding element 1 shown in FIGS is formed as a one-piece stamped and bent part made of metal, here from a spring plate.
• the holding element 1 comprises a flat spring section 5, which is biased in the state shown in FIGS. 1 and 3 by bending transversely to its longitudinal extent.
• the angle of attack ⁇ marked in FIG. 3 determines the contact force F A , with which the commutator sliding contact 2 rests on the outer circumference of the commutator 3.
• the spring section 5 is designed such that the edge fiber stresses of a subsection 6 of the spring section 5 are at least approximately constant in the longitudinal direction of the subsection 6.
• the spring section 5 tapers in the direction of the holding section 7, ie its width formed from solid material (transversely to the longitudinal extension) decreases symmetrically with respect to a non-illustrated longitudinal central axis.
• the length Io of the partial section 6 essentially corresponds to the total length of the spring section 5 - the length Io of the partial section 6 is shorter than the total length of the spring section 5 only by the minimum distance a Holding portion 7 adjacent region (length a) of the spring portion 5 takes the width not linearly as viewed in the section 6 in the direction of the holding section 7, but even by the provision of outwardly curved transition radii 8.
• the disadvantage of non-constant edge fiber stresses is accepted in the boundary region of the minimum length a to the holding section 7 in the embodiment shown in order to avoid loss of strength due to a notch effect that would occur if the spring section 5 sharp or with minimal transition radii in the holding section 7 would.
• the spring portion 5 is adjacent to its in the drawing plane left end 9, at which its width is bo, to a mounting portion 10, which in the embodiment shown a tab for sliding on a Walkerdom 11th (see Fig. 3).
• a mounting portion 10 which in the embodiment shown a tab for sliding on a Gardom 11th (see Fig. 3).
• the support member 1 is supported in the carrier part 14 shown in FIG. 3 made of plastic.
• the point indicated by the arrow 13 coincides with the left in the drawing plane, ie, facing away from the holding section 7 end 9 of the spring portion 5 together.
• Alternative embodiments of the attachment portion 10, for example with a detent geometry are also feasible. Additionally or alternatively, the attachment portion 10 can be embossed with the support member 14.
• Non-resilient ground plane 16 of the holding portion 7 Along both longitudinal sides of the holding portion 7 protrude outward resilient curved side walls 17, which serve for lateral guidance of KommutatorschleifANDes, which is received in a through hole 18, the rigid ground plane 16 penetrated.
• the passage opening 18 is bounded laterally by four spring tabs 19 which are each offset by 90 ° and which receive the commutator sliding contact 2 in a clamping manner between them.
• the spring tabs 19 extend in the direction of curvature of the holding element 1, whereas the side walls 17 are directed in an opposite direction.
• Fig. 3 the support member 14 (brush holder) with three holding elements 1 is shown.
• the three holding elements 1 each hold a KommutatorschleifCount 2 by clamping and spring-loaded in the radial direction inwardly with a spring force on the non-rotatably connected to a not shown armature shaft commutator 3.
• the illustrated electric motor 4 is a between two power levels switchable electric motor, wherein the holding elements 1 shown in the right half of the drawing are arranged such that a targeted Fehlkommut réelle can be realized.
• the total width of the spring section 5 is constant and corresponds at each position x along the longitudinal extension of the spring section 5 of the starting width bo. Nevertheless, the width extension of the spring section 5 formed by solid material is reduced in the longitudinal direction of the spring section 5 towards the holding section 7.
• the width extension formed by solid material obeys at least approximately the formula:

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

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (6)

Families Citing this family (7)

Citations (3)

Family Cites Families (10)

• 2007
  • 2007-12-20 DE DE102007061745A patent/DE102007061745A1/de not_active Withdrawn
• 2008
  • 2008-10-27 EP EP08864586A patent/EP2235801A1/de not_active Withdrawn
  • 2008-10-27 CN CN2008801214689A patent/CN101904059B/zh not_active Expired - Fee Related
  • 2008-10-27 KR KR1020107013474A patent/KR101518797B1/ko not_active IP Right Cessation
  • 2008-10-27 WO PCT/EP2008/064494 patent/WO2009080391A1/de active Application Filing
  • 2008-10-27 JP JP2010538518A patent/JP5553768B2/ja not_active Expired - Fee Related

Patent Citations (3)

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