Patent US5115325A successfully refreshed from Google Patents.
Patent EP0340029B1 successfully refreshed from Google Patents.
EP0340029B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electric motor
Assignee: Dynamic Systems International Inc Canada
•
Filing: 1989-04-28
•
Granted: 1994-07-13
•
Expires: 2009-04-28
Abstract
Abstract A modular, expandable, low-weight electric motor (10) has a cylindrical, non-magnetic casing (12) formed in axially-aligned sections (28, 30, 32). The casing sections (28, 30, 32) are releasably connected to define a unitary structure with a polygonal exterior surface (22) and a circular interior surface (24). Separate U-shaped stator pole assemblies (58, 84, 86) are releasably mounted against the exterior (24) of the casing (12), each casing section carrying the poles (62, 64) associated with a different motor phase. The poles (62, 64) extending through apertures into the interior of the casing (12), and have active pole faces (66, 68) which are curved and substantially flush with the circular interior surface (24) of the casing (12). A modular rotor (16) is mounted in the interior of the casing (12) and carries magnetic elements (114, 116) in axially spaced-apart sets corresponding to each motor phase. The active faces of the magnetic elements are curved and oriented in a cylindrical arrangement. During each rotation of the rotor (16), the pole faces of each motor phase simultaneously and repeatedly register with the associated magnetic element faces forming air gaps (110, 112), and the magnetic elements (114, 116) simultaneously complete local magnetic circuits (118) with each stator pole assembly. The sets of magnetic rotor elements (114, 116) are indexed circumferentially relative to one another such that the motor is self-starting.
Inventors
- 👤 Lyman Richardson
- 👤 Wojciech Mizera
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 16:42
CPC Classifications
H; H02; H02K; H02K19/00; H02K19/02; H02K19/10; H02K19/103
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
582 words
An electric motor (10 or 170) comprising a stator (14), a generally cylindrical casing (12 or 172) with an exterior surface (24) and an interior surface (26) for the stator (14) and a rotor (16 and 176) mounted in the interior of the casing (12 or 172) and supported for rotation about a rotational axis (22) relative to the casing (12 or 172), the motor (10 or 170) being characterized by: a multiplicity of apertures (38 or 186) extending between the exterior surface (24) and the interior surface (26)of the casing (12 or 172); the stator (14) comprising a multiplicity of separate stator pole assemblies (54 or 190), each of the stator pole assemblies (54 or 190) comprising at least a pair of magnetically-coupled poles (62, 64) and electrically-operable coil means (70, 72) operatively coupled to the stator pole assembly (54 or 190) to produce a magnetic field in each of the stator poles (62, 64), each of the stator poles having a pole face (66 or 68); means (72, 74, 76, 80, 82) releasably mounting each of the stator pole assemblies (54 or 190) onto the exterior surface (24) of the casing (12 or 172) with the associated coil means (70, 72) external to the casing (12 or 172) and the associated poles (62, 64) extending through the apertures (36 or 186) of the casing (12 or 172), the stator pole assemblies (54 or 190) being spaced-apart circumferentially about the exterior surface (24) of the casing (12 or 172), the pole faces (66, 68) associated with the multiplicity of stator pole assemblies (54 or 190) being oriented in a cylindrical arrangement centered about the rotational axis (22) with a predetermined radius; the rotor (16 or 176) having a support portion (20 or 200) and a multiplicity of magnetic elements (114, 116 or 208) attached to and spaced-apart circumferentially about the support portion (20 or 200), each of the magnetic elements (114, 116 or 208) having an element face, the element faces of the magnetic elements (114, 116 or 208) being oriented in a cylindrical arrangement centered about the rotational axis (22) with a radius which is smaller by a predetermined amount than the radius of the cylindrical arrangement of the faces (66, 68); and the pole faces (66, 68) and the magnetic element faces being arranged such that, during each rotation of the rotor (16, 176), the poles faces (66, 68) of the multiplicity of stator pole assemblies (54 or 190) simultaneously and repeatedly register with the faces of the magnetic elements (114, 116 or 208) to form at each of the pole faces (66, 68) an air gap (110 or 112; or 210 or 212) having a radial dimension corresponding to the predetermined amount and such that the magnetic elements (114, 116 or 208) complete a local magnetic circuit (108) with each of the stator pole assemblies (54 or 190) whenever the air gaps (110, 112 or 210, 212) are formed, the local magnetic circuit (108) associated with each stator pole assembly (54 or 190) comprising the magnetically coupled stator poles (62, 64) of the associated stator pole assembly (54 or 190), the air gaps (110, 112 or 210, 212) formed at the pole faces (66, 68) of the associated stator pole assembly (54 or 190), and the magnetic element or elements (114, 116 or 208) defining the air gaps (110, 112 or 210, 212) with the pole faces (66, 68) of the associated stator pole assembly (54 or 190).
Claim 2
Dependent Claim
60 words
An electric motor (10 or 170) according to claim 1, characterised in that the casing (12 or 172) is formed of non-magnetic material which has a specific mass lower than that of materials constituting the poles (62, 64) of the stator pole assemblies (54 or 190) and the magnetic elements (114, 116 or 208) of the rotor (16 or 176).
Claim 3
Dependent Claim
80 words
An electric motor (10 or 170) according to claim 1 or 2, characterised in that each of the stator pole assemblies (54) comprises a generally U-shaped member (60) formed of magnetic material, the U-shaped members (60) of the stator pole assemblies (54) being located in a common plane perpendicular to the rotational axis (22), and the pole faces (66, 68) of the multiplicity of stator pole assemblies (54) being equally spaced-apart circumferentially in the common plane by a predetermined angle.
Claim 4
Dependent Claim
56 words
An electric motor (170) according to claim 1 or 2, characterised in that each of the stator pole assemblies (190) comprises a generally U-shaped member formed of magnetic material, each of the U-shaped members is aligned with a plane containing the rotational axis (22), and the U-shaped members (60) are in registration circumferentially and equally-spaced circumferentially.
Claim 5
Dependent Claim
112 words
An electric motor (10 or 170) according to any preceding claim, characterised in that the multiplicity of stator pole assemblies (54 or 190) and the multiplicity of magnetic elements (114, 116 or 208) constitute a first phase of the electric motor (10 or 170), the electric motor (10 or 170) comprising second and third additional motor phases substantially identical to the first phase, the second and third motor phases comprising stator pole assemblies (84, 86 or 192, 194) mounted on the exterior of the casing (12 or 172) and magnetic elements (154, 156 or 216, 218) attached to the support portion (20 or 200, 202, 204) of the rotor (16 or 176).
Claim 6
Dependent Claim
89 words
An electric motor (10 or 170) according to claim 5, characterised in that the magnetic elements (54, 84, 86 or 190, 192, 194) of each of the motor phases are indexed circumferentially relative to the magnetic elements (54, 84, 86 or 190, 192, 194) of the other motor phases such that at least one of the motor phases is capable of generating a torque to rotate the motor (16 or 176) at any given time when the coil means (70, 72) associated with the one motor phase are electrically-energized.
Claim 7
Dependent Claim
184 words
An electric motor (10) according to claim 5 or 6, characterised in that the support portion (20) of the rotor (16) has a generally cylindrical outer surface formed with open-ended longitudinal grooves (146, 148, 150); the rotor (16) comprises a multiplicity of identical annular plates (138) of magnetic material, each plate (138) having a central opening which receives the support portion (20) and tabs (142, 144) extending radially inwardly into the grooves (146) of the support portion (20 or 200), each plate (138) having a periphery formed with a multiplicity of tabs which extend radially outwardly and which are equally spaced circumferentially about the periphery; and, the rotor (16) comprises spacers (130, 132) separating the plates (138) into three sets of plates in axially side-by-side relationship, each set of plates defining an annular member (100, 102 or 104) with peripheral teeth (114, 116, 154, 156) which are equally-spaced circumferentially by a common predetermined angle, the teeth (114, 116, 154, 156) of each annular member (100, 102 or 104) constituting the magnetic elements (114, 116, 154, 156) of a different one of the motor phases.
Claim 8
Dependent Claim
171 words
An electric motor (10) according to claim 7, characterised in that the grooves (146, 148, 150) of the support member are arranged in sets of grooves (146, 148, 150), one set of grooves (146, 148 or 150) being associated with each of the annular members (100, 102 or 104) and receiving the tabs (142, 144) of the plates (138) defining the annular member (100); the sets of grooves (146, 148, 150) being circumferentially arranged such that the teeth (114, 116, 154, 156) associated with each of the annular members (100, 102, 104) are indexed circumferentially by a fraction of the common predetermined angle relative to the teeth (114, 116, 154, 156) of the other annular members (100, 102, 104), the fraction being selected such that at least one of the motor phases is capable of generating a torque to rotate the rotor (16) at any given time when the coil means (70, 72) associated with the stator pole assemblies (54 or 190) of the at least one motor phase are electrically-energized.
Claim 9
Dependent Claim
58 words
An electric motor according to claim 1, characterised in that the stator pole assemblies (240) comprises a housing (228) formed of a heat-conducting material and the coil means (242) and the poles (244, 246) of the stator pole assembly (240) are mounted within the housing (228) with the poles (244, 246) extending from the interior of the housing.
Claim 10
Dependent Claim
42 words
An electric motor according to claim 9, characterised in that the interior of each housing (228) contains a heat-conductive material (248) intimately contacting the housing (228) and each of the poles (244, 246) and coil means (242) mounted within the housing (228).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.