Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
  • F16D1/06—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end
  • F16D1/064—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end non-disconnectable
  • F16D1/072—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end non-disconnectable involving plastic deformation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
  • B21K1/00—Making machine elements
  • B21K1/28—Making machine elements wheels; discs
  • B21K1/30—Making machine elements wheels; discs with gear-teeth
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
  • F16D1/10—Quick-acting couplings in which the parts are connected by simply bringing them together axially
  • F16D1/104—Quick-acting couplings in which the parts are connected by simply bringing them together axially having retaining means rotating with the coupling and acting only by friction
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K1/00—Details of the magnetic circuit
  • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
  • H02K1/22—Rotating parts of the magnetic circuit
  • H02K1/28—Means for mounting or fastening rotating magnetic parts on to, or to, the rotor structures
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
  • H02K15/02—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies
  • H02K15/024—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies with slots
  • H02K15/028—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies with slots for fastening to casing or support, respectively to shaft or hub
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
  • F16D1/06—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end
  • F16D1/08—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end with clamping hub; with hub and longitudinal key
  • F16D1/0852—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end with clamping hub; with hub and longitudinal key with radial clamping between the mating surfaces of the hub and shaft
  • F16D1/0858—Couplings for rigidly connecting two coaxial shafts or other movable machine elements for attachment of a member on a shaft or on a shaft-end with clamping hub; with hub and longitudinal key with radial clamping between the mating surfaces of the hub and shaft due to the elasticity of the hub (including shrink fits)
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
  • F16D1/10—Quick-acting couplings in which the parts are connected by simply bringing them together axially
  • F16D2001/103—Quick-acting couplings in which the parts are connected by simply bringing them together axially the torque is transmitted via splined connections

Definitions

• the present invention relates to a shaft with a central axis and a fitting section for forming a form-fitting shaft-hub connection, the fitting section radially protruding fitting structures and one formed at an axial end of the fitting section which Has fitting structures at least partially grasping chamfer.
• the invention relates to a forming tool for producing a shaft, a method for producing a shaft and a rotor for an electrical machine.
• a wave is from the article by M. Lecker et al. "Investigations into the transfer behavior of knurled press connections made of steel-aluminum", Research in Engineering 79, pages 41 to 65 (2015) known.
• the article discloses a knurled shaft with axially parallel knurls which are produced by reshaping by means of a knurling wheel or by means of recursive axial shaping and have a bevel with a bevel angle f.
• a form-fitting shaft-hub connection can be realized by a cutting and / or reshaping joining process.
• a disadvantage of such a shaft is that the hub material is displaced essentially in the radial direction during a joining process in a hub. As a result, considerable radial mechanical stresses occur in the hub material. This is particularly undesirable with regard to the use of a shaft as a rotor shaft for a drive machine of an electric vehicle.
• the invention is therefore based on the object of specifying a possibility for reducing radial mechanical stresses in a self-tapping, form-fitting shaft-hub connection. According to the invention, this object is achieved by a shaft of the type mentioned at the outset, in which a distance between radially inner edges of a respective fitting structure and the axial end is reduced.
• the invention is based on the consideration of designing the fitting structures to run narrower towards the axial end so that hub material displaced during a joining process can get into gaps between the radially inner edges of adjacent fitting structures.
• This hub material thus does not reach the outside radially in order to contribute to the generation of radial mechanical stresses there.
• radial mechanical stresses can advantageously be reduced considerably and, at the same time, losses in the torque transmission capacity of the shaft-hub connection can be avoided.
• a radial deformation caused by the radial mechanical stresses is reduced when the shaft is rotating.
• the radially inner edges converge at one point towards the axial end.
• an essentially pointed configuration of the fit structure is realized, which considerably facilitates the displacement of the material during the joining process.
• the radially inner edges each run straight at an angle with respect to a line parallel to the central axis towards the axial end.
• the angle is preferably less than 90 °. It is particularly preferably between 10 ° and 60 °.
• the radially inner edges each run towards the side line with the formation of an arc.
• the arc is preferably an arc of a circle with a constant radius. In a preferred embodiment, one closes from the beginning
• the chord of the arch running to the end of the arch forms an angle between 10 ° and 60 ° with a line parallel to the central axis.
• the bevel begins closer to the axial end than a point closest to the axial end of the maximum distance between the radially inner edges.
• the area of the radially inner edges in which their distance from the axial end decreases extends further in the axial direction than the bevel. In this way, a particularly large amount of space is made available to accommodate the hub material displaced during the joining process.
• a ratio of an axial extension of the region of the radially inner edges in which their distance from the axial end decreases to an axial extension of a region in which the fitting structure is gripped is between 1.8 and 2.2.
• a respective fitting structure of the shaft according to the invention can have flat side surfaces. These preferably include an angle between 30 ° and 70 ° with a plane perpendicular to the circumferential direction.
• a respective fitting structure can have curved side surfaces which preferably have a chord enclosing an angle between 30 ° and 70 ° with a plane perpendicular to the circumferential direction.
• a respective fitting structure has the shape of a polygon or a rounded polygon with respect to a cross-sectional area perpendicular to the central axis.
• the polygon is preferably a triangle or a rectangle.
• a respective fit structure with respect to a perpendicular to the central axis cross-sectional area have the shape of a semicircle or semi-oval.
• the fitting section has a plurality of fitting zones with fitting structures distributed in the circumferential direction and is smooth between two adjacent fitting zones. Preferably, three evenly distributed fitting zones are provided.
• a forming tool for producing a shaft in particular a shaft according to the invention, comprising a die with a through opening for passing through a chamfered shaft body, the die having recesses in an inner edge of the through opening for forming fitting structures on the Has shaft body, wherein a distance between radially inner edges of a respective recess decreases towards the axially inside of the through opening.
• the recesses are expediently designed to be opposite to the areas of the fitting structures in which the distance between their radially inner edges is reduced.
• the radially inner edges converge at one point towards the axially interior of the through opening.
• the radially inner edges can each run straight at an angle with respect to a line parallel to a central axis of the through opening towards the axially inside of the through opening.
• the angle can be between 10 ° and 60 °.
• the radially inner edges can each run towards the axially inside of the through opening, forming an arc.
• a tendon of the bow running from the beginning to the end of the bow closes preferably an angle between 10 ° and 60 ° with a line parallel to a central axis of the through opening.
• a respective recess flat side surfaces which preferably enclose an angle between 30 ° and 70 ° with a plane perpendicular to the circumferential direction, or curved side surfaces, which preferably form an angle between 30 ° and 70 ° having an enclosing chord with a plane perpendicular to the circumferential direction.
• a respective recess of the tool according to the invention can have the shape of a polygon or a rounded polygon with respect to a cross-sectional area perpendicular to the central axis of the through opening, the polygon preferably being a triangle or a rectangle, or the shape of a semicircle or semi-oval.
• the die can be formed by several, preferably three, separate die elements attached to a support of the forming tool, each die element having several of the recesses and being smooth in the circumferential direction to one or both adjacent die elements.
• the object on which the invention is based is further achieved by a method for producing a shaft, comprising the following steps: providing a shaft body, forming a fitting section with radially protruding fitting structures which are at least partially covered by a chamfer at an axial end of the fitting section, whereby a distance between radially inner edges of a respective fitting structure towards the axial end is reduced.
• a forming tool according to the invention is preferably used to form the fit structures.
• a shaft body with existing fitting structures and an existing bevel that encompasses the existing fitting structures is provided at the axial end.
• a volume correspondence between a volume of an area of a respective existing existing fitting structure, which is covered by the existing bevel and delimited by a plane perpendicular to the central axis, and a volume of an area of a respective fitting structure of the Shaft, in which the distance between the radially inner edges decreases towards the axial end and is limited by a plane perpendicular to the central axis, is generated by at least 95%, preferably at least 99%. Because the volumes become similarly large, undesired deformations, for example, forming a burr, can be avoided.
• a rotor for an electrical machine preferably a drive machine for an electric vehicle, comprising a shaft according to the invention or a shaft obtained by the method according to the invention and a rotor core and / or a resolver positively connected to the fitting section .
• Permanent magnets are preferably arranged in the rotor core. Further advantages and details of the present invention emerge from the exemplary embodiments described below and with reference to the drawings. These are schematic representations and show:
• 1 shows a perspective view of a first exemplary embodiment of the shaft according to the invention
• 2 shows a detailed view of a fitting structure of the first exemplary embodiment and a second exemplary embodiment of the shaft according to the invention from a radial perspective
• 3 shows a detailed view of the fit structure according to the first and second exemplary embodiment from a side perspective
• FIG. 4 shows sectional views of the fit structure along sectional planes A-A and B-B in FIG. 2;
• FIG. 5 shows a detailed view of a fitting structure according to a third and a fourth exemplary embodiment of the shaft according to the invention from a radial perspective; 6 shows a detailed illustration of the fitting structure according to the third and fourth exemplary embodiments from a side perspective;
• FIG. 7 shows sectional views of a fit structure according to further exemplary embodiments of the shaft according to the invention.
• FIG. 8 shows a perspective illustration of an exemplary embodiment of the forming tool according to the invention.
• FIG. 10 shows a schematic diagram of an existing fitting structure before an embodiment of the method according to the invention is carried out
• 11 shows a schematic diagram of a fit structure after the exemplary embodiment of the method according to the invention has been carried out; 12 shows a schematic diagram of an exemplary embodiment of the rotor according to the invention in an electrical machine;
• FIG. H shows a detailed view of FIG. 13.
• FIG. 1 is a perspective view of a first embodiment of a shaft 1.
• the shaft 1 has a central axis 2 and a fitting section 3 for forming a form-fitting shaft-hub connection.
• Radially protruding fitting structures 4 in the form of knurls are formed in the fitting section.
• a bevel 6 is formed which partially encompasses the fitting structures 4.
• the fitting section 3 in this embodiment example extends further in the axial direction on both sides than the fitting structures 4.
• stub shafts close 8, 9 at.
• FIG. 2 is a detailed view of a fitting structure 4 of the first exemplary embodiment and a second exemplary embodiment of a shaft 1 from a radial perspective.
• Radially inner edges 10, 11 of the fitting structure 4 which is representative of the remaining fitting structures 4 shown in FIG. 1, reduce their distance towards the axial end 5 and converge at a point 12. From a maximum distance b between the radially inner edges of the fitting structure 4, this distance decreases further and further to the axial end 5 from a predetermined axial position 13 until it is practically zero.
• the radially inner edges 10, 11 each run straight at an angle l with respect to a line 14 parallel to the central axis 2 towards the axial end 5.
• the second exemplary embodiment differs from the first exemplary embodiment in that the radially inner edges 10, 11 here run towards the axial end 5 with the formation of an arc shown in dashed lines.
• this arc has a constant radius.
• a chord 15 of the arc running from the beginning to the end of the arc or from the axial position 13 to the point 12 encloses the angle l with the line 14 parallel to the central axis 2.
• FIG 3 is a detailed view of the fitting structure 4 according to the first and second exemplary embodiment from a side perspective.
• FIG. 3 a maximum height h of the fit structure is initially shown. This corresponds to a radial distance between the radially inner edges 10, 11 and a radially outer edge 16 of the fit structure outside the chamfered area.
• a bevel angle of the bevel 6 is denoted by f.
• the bevel 6 begins visibly closer to the axial end 5 than a point closest to the end face (axial position 13) of the maximum distance between the radially inner edges 10, 11.
• a ratio of an axial extent h of the area in which the distance between the radially inner edges 10 is , 11 reduced towards a radial extension h, a region in which the fitting structure 4 is chamfered, is 2.0 here and is typically between 1.8 and 2.2.
• a respective side surface 17 of the fitting section 4 therefore has a triangular shape when viewed in the circumferential direction.
• FIG. 4 shows two sectional illustrations of the fitting structure 4 along sectional planes AA and BB in FIG. 2.
• the side surfaces 17 enclose an angle y with a plane perpendicular to the circumferential direction or a plane spanned in the axial direction and radial direction, which extends through the radially outer edge 14. In other words, it becomes a radially inner distance Ci of the side surfaces
• the side surfaces 17 are curved outward in the circumferential direction, a chord of the curvature making the angle y with the plane
• FIGS. 5 and 6 are each a detailed representation of a fitting structure 4 according to a third and a fourth exemplary embodiment of the shaft 1, FIG.
• FIG. 5 shows the fitting structure 4 from a radial perspective
• FIG. 6 shows the fitting structure 4 from a side perspective.
• the side surfaces 17 do not extend up to the maximum height h of the fitting structure 4, so that a radially outer section 19 of the fitting structure 4 pointing towards the axial end 5 is flattened and runs at the bevel angle f .
• FIG. 7 shows sectional representations of fitting structures 4 according to further exemplary embodiments of the shaft 1, the representation corresponding to the sectional plane AA in FIG. 4.
• the fitting structure 4 has a radially inner parallel section 20 and a radially outer round section 21.
• the fitting structure 4 has a hexagonal cross section with a radially inner trapezoidal section 22 and a radially outer one trapezoidal section 23.
• the fitting section is pentagonal and has a radially inner parallel section 20 and a radially outer triangular section 24.
• the fitting section 4 has an essentially parabolic cross section.
• fitting sections 4 instead of fitting structures 4 arranged continuously in the circumferential direction, a plurality of fitting zones distributed in the circumferential direction are provided in the fitting section 3, in which the fitting structures 4 are formed, with no fitting structures being or being formed between the fitting zones.
• the fitting section 3 is smooth in the circumferential direction between the fitting zones.
• three fitting zones can be provided, which are arranged at an angle of 120 ° to one another in the circumferential direction.
• FIG. 8 is a perspective illustration of an exemplary embodiment of a forming tool 50 for producing a shaft 1.
• an exemplary embodiment of a method for producing the shaft 1 is also described below.
• the forming tool 50 comprises a die 51 with a through opening 52 having a central axis 53 for passing through a chamfered shaft body.
• a shaft body in such a shaft body - as shown in FIG. 10 - already existing fitting structures are provided which are gripped at an existing bevel angle cpo.
• the die 51 has recesses 55 in an inner edge 54 of the through opening 52 for forming the fitting sections 4 on the shaft body.
• 9 is a detailed view of the depressions 55 of the forming tool 50.
• the depressions 55 are evidently formed opposite to the intended shape of the fitting structures 4, which is generally one of the previously described Embodiments of the shaft 1 can correspond.
• the depressions 55 thus above all have radially inner edges 56, 57, the spacing of which decreases towards the axially interior of the through opening 52.
• the recesses are not formed completely circumferentially, but are only formed in three recess zones 58 spaced apart in the circumferential direction, so that the forming tool 50 shown is designed for forming a shaft 1 with the corresponding fitting zones described above . According to further exemplary embodiments of the forming tool 50, however, this can also have recesses 55 distributed completely in the circumferential direction, so that a shaft can be produced in as shown in FIG. 1.
• the die 51 is formed by three die elements 59 which are separate from one another and which each have corresponding recesses 55 of one of the recess zones 58 and to this extent are of identical design.
• the die elements 59 are arranged in a carrier 60, which is also penetrated by the through opening 52, and fastened there by fastening means 61, here screws as an example.
• the shaft body is first provided.
• 10 shows a perspective view of an existing fitting structure 4a on a shaft body before the production method is carried out.
• a width t of the existing fitting structure 4a and an axial length xi of the region of the existing fitting structure 4a covered by the bevel are also identified.
• H denotes the height of the existing fitting structure 4a and cpoden existing bevel angles.
• a volume of a region of the existing fitting structure 4a which points towards the axial end 5 and which is covered by the existing chamfer is identified by Vi.
• the shaft body with the existing fitting structures 4a first is introduced into the through opening of the tool 50, so that the existing fitting structure 4a is plastically deformed.
• FIG. 11 shows the geometric relationships of the fitting structure 4 after the deformation in the tool 50, the angles f, l, y being produced.
• An axial length of the region of the fitting structure 4 covered by the bevel 6 is designated by X2.
• X3 denotes an axial length between the area in which the distance between the radially inner edges 10, 11 and the axial end 5 decreases by the area of the fitting structure 4 covered by the bevel 6.
• the volume, shown subdivided into partial volumes V2.1, V2.2, of the area pointing towards the axial end 5, in which the distance between the radially inner edges 10, 11 and the axial end 5 decreases, is denoted by V2.
• the existing fitting structures 4a and the shape of the recesses 55 of the die 51 are selected in such a way that a volume correspondence of at least 99% between V1 and V2 is achieved. It should be noted here that the bevel angle changes from ⁇ po to f during the formation of the fitting structure 4.
• FIG. 12 is a schematic diagram of an electrical machine 100 with an exemplary embodiment of a rotor 101.
• the rotor 101 comprises a shaft 1 according to one of the exemplary embodiments described above, a rotor core 102 with permanent magnets being arranged in a form-fitting manner on the fitting section 3.
• the rotor 101 is mounted within a stator 103 so that it can rotate about the central axis 2.
• FIG. 13 and 14 each show the production of a shaft-hub connection of the rotor, FIG. 14 showing a detail Z in FIG. It can be seen that the shaft 1 is inserted into the rotor core 102 in order to produce the shaft-hub connection.
• the fitting section 4 has a radial oversize U with respect to the rotor core 102.
• a form-fitting shaft-hub connection between the shaft 1 and the rotor core 102 is realized by cutting and reshaping the rotor core 102.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Power Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)
• Manufacture Of Motors, Generators (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=75746584

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Family Cites Families (5)

• 2020
  • 2020-04-29 DE DE102020111679.9A patent/DE102020111679A1/de active Pending
• 2021
  • 2021-04-23 EP EP21722387.4A patent/EP4142962A1/de active Pending
  • 2021-04-23 WO PCT/EP2021/060617 patent/WO2021219497A1/de unknown
  • 2021-04-23 CN CN202180030972.3A patent/CN115461170A/zh active Pending

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