# US 10,770,934 B2 · Electrical machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,770,934 B2 - Document ID: US10770934B2 - Status: Granted - Kind: B2 - Application number: 15/548,287 - Filed: 2016-01-22 - Published: 2018-01-11 - Granted: 2020-09-08 - Earliest claimed: 2015-02-03 - Assignees: Reishauer AG - Applicants: Reishauer AG - Inventors: Ronald Jakob; Roman Fürderer; Erwin Sennhauser - Web page: https://patentgrep.com/patent/US10770934B2 ## CPC - H02K 1/185: {to outer stators} - H02K 5/15: Mounting arrangements for bearing-shields or end plates - H02K 5/1732: {radially supporting the rotary shaft at both ends of the rotor (H02K5/1737 takes precedence)} - H02K 5/203: {specially adapted for liquids, e.g. cooling jackets} - H02K 5/24: specially adapted for suppression or reduction of noise or vibrations - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract The invention relates to an electrical machine having a rotor (1), a stator (2) radially surrounding the rotor, and a housing (4) radially surrounding the stator. In order to minimize stresses in the housing and nonetheless decrease the tendency of the stator to torsional vibrations, the stator is connected to the housing at least at one end in a radially and torsionally rigid but axially movable manner, for example, by way of an axially compliant material area. The electrical machine can, in particular, be a motor spindle in a gear finishing machine. ## Claims ### Claim 1 An electrical machine, comprising: a rotor that is rotatably supported around an axis of rotation and defines an axial direction with its axis of rotation; a stator radially surrounding the rotor, the stator having a distal end and a proximal end; and a housing radially surrounding the stator, wherein the stator, at at least one of its distal end and its proximal end, is connected to the housing by a connection that is radially and torsionally stiff while facilitating axial movability of said at least one of its distal end and its proximal end relative to the housing. ### Claim 2 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator comprises a stator sleeve that radially delimits the stator outwardly, and wherein the stator is connected to the housing by means of the stator sleeve. ### Claim 3 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator, at at least one of its distal end and its proximal end, is connected to the housing via an axially compliant material section. ### Claim 4 (depends on 3) The electrical machine as claimed in claim 3, wherein the axially compliant material section has a spring constant in an axial direction and in linear approximation of at most 5000 newton per micrometer. ### Claim 5 (depends on 3) The electrical machine as claimed in claim 3, wherein the axially compliant material section has an annular flange shape. ### Claim 6 (depends on 5) The electrical machine as claimed in claim 5, wherein the axially compliant material section has an inner circumference and an outer circumference, wherein the axially compliant material section is connected at its outer circumference axially, radially and torsionally stiff with the stator, and wherein the axially compliant material section is connected at its outer circumference axially, radially and torsionally stiff with the housing, or vice versa. ### Claim 7 (depends on 3) The electrical machine as claimed in claim 3, wherein the axially compliant material section is formed from metal and has a thickness in an axial direction of 0.5-8 millimeters. ### Claim 8 (depends on 3) The electrical machine as claimed in claim 3, wherein the axially compliant material section is formed in one piece with a housing element and is connected axially, radially and torsionally stiff with the stator. ### Claim 9 (depends on 8) The electrical machine as claimed in claim 8, wherein the housing element is a bearing shield of the housing. ### Claim 10 (depends on 3) The electrical machine as claimed in claim 3, comprising a retaining ring that is formed separately from the stator and from the housing, wherein the retaining ring is connected axially, radially and torsionally stiff both with the stator as well as the housing and forms the axially compliant material section. ### Claim 11 (depends on 10) The electrical machine as claimed in claim 10, comprising a first and a second clamping ring, wherein the retaining ring is pressed at its outer circumference onto the stator by the first clamping ring and at its inner circumference onto the housing by the second clamping ring, or vice versa. ### Claim 12 (depends on 3) The electrical machine as claimed in claim 3, wherein the axially compliant material section is formed in one piece with a stator element and connected axially, radially and torsionally stiff with a housing element. ### Claim 13 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator is connected to the housing such that an axial tensile force or an axial compressive force acts on the stator if the stator and the housing exhibit the same temperature. ### Claim 14 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator is connected at its distal end axially, radially and torsionally stiff to the housing, and wherein the stator is connected only at its proximal end radially and torsionally stiff but axially movably to the housing. ### Claim 15 (depends on 14) The electrical machine as claimed in claim 14, wherein the stator, at its distal end, is connected to the housing by means of a form-fit or friction-locked connection. ### Claim 16 (depends on 15) The electrical machine as claimed in claim 15, wherein the distal end of the stator is connected to the housing by means of multiple axially, tangentially or radially arranged threaded elements and/or pins and/or wedges. ### Claim 17 (depends on 15) The electrical machine as claimed in claim 15, wherein the distal end of the stator is connected to the housing via a Hirth joint. ### Claim 18 (depends on 1) The electrical machine as claimed in claim 1, wherein the electrical machine comprises a first bearing for the rotor distally from the distal end of the stator and comprises a second bearing for the rotor proximally from the proximal end of the stator, and wherein the first bearing is formed axially as a fixed bearing and the second bearing is formed axially as a floating bearing. ### Claim 19 (depends on 1) The electrical machine as claimed in claim 1, wherein the electrical machine is a motor spindle for a machine tool. ### Claim 20 (depends on 1) A manufacturing method for an electrical machine as claimed in claim 1, comprising: providing a stator sleeve and an element to be connected to one end of the stator sleeve, wherein an axial oversize exists between the stator sleeve and the element; installing the stator sleeve and the element when they exhibit the same temperature to determine the oversize; separating the stator sleeve and the element; refinishing the end of the stator sleeve and/or the element to be connected in such a manner, (a) that the axial oversize will be eliminated, or (b) that a reduced axial oversize remains to exert an axial compressive force on the stator sleeve following assembly of the electrical machine, or (c) that a negative axial allowance is created to exert an axial tensile force on the stator sleeve following assembly of the electrical machine; and refitting the stator sleeve and the element. ### Claim 21 (depends on 1) The electrical machine as claimed in claim 1, wherein the connection is radially and torsionally free of play. ### Claim 22 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator, at each of its distal end and its proximal end, is connected to the housing by a connection that is radially and torsionally stiff, and wherein the connection, at at least one of the distal end and the proximal end, facilitates axial movability of said at least one of its distal end and its proximal end relative to the housing. ### Claim 23 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator, at each of its distal end and its proximal end, is connected to the housing by a connection that is radially and torsionally stiff and free of play, and wherein the connection, at at least one of the distal end and the proximal end, facilitates axial movability of said end relative to the housing. ### Claim 24 (depends on 1) The electrical machine as claimed in claim 1, wherein the stator and the rotor form an electric motor.