US3831268A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making an electric motor armature core
Assignee: Briggs and Stratton Corp
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Filing: 1973-12-03
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Granted: 1974-08-27
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Expires: 1993-12-03
Abstract
Abstract An armature core assembly in which the heads of the circumferentially spaced T-shaped teeth that form the peripheral oortion of the laminated coilreceiving core have their opposite end portions taperingly deformed to widen the entrances to the reentrant coil receiving spaces or slots between the T-shaped teeth at opposite ends of the core. A preformed plastic shield or cap of the same size and shape as the laminations which comprise the core, completely covers each end of the core and has protective flanges that embrance the ends of its T-shaped teeth, including the head, the taperingly reduced width of the end portions of the head providing space for those portions of the protective flanges that embrace the heads, so that the presence of these protective flanges does not objectionably reduce the width of the entrances to the wire receiving slots.
Inventors
- 👤 E Boyd
- 👤 J Harkness
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:09
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/22; H02K1/26; H02K15/00; H02K15/02; H02K15/021; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49009; Y10T29/49012; Y10T29/4902; Y10T29/49075; Y10T29/49078; Y10T29/49826; Y10T29/49945; Y10T29/53; Y10T29/5313; Y10T29/53143; Y10T29/53161; Y10T29/5317
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
151 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent Teeth of the laminations, said method being characterized by: deforming the heads of the T-shaped teeth on a plurality of the endmost laminations at both ends of the stack by bending the extremities of the heads inwardly with a progressively lesser curvature on the inwardly successive laminations, to thereby taperingly enlarge the entrances to the winding receiving slots at both ends of the core and provide smooth surfaces for said entrances.
Claim 2
Independent Claim
151 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent Teeth of the laminations, said method being characterized by: deforming the heads of the T-shaped teeth on a plurality of the endmost laminations at both ends of the stack by bending the extremities of the heads inwardly with a progressively lesser curvature on the inwardly successive laminations, to thereby taperingly enlarge the entrances to the winding receiving slots at both ends of the core and provide smooth surfaces for said entrances.
Claim 3
Dependent Claim
24 words
The method of claim 1, wherein said deformation of the heads of the T-shaped teeth is done by inserting a wedge between adjacent teeth.
Claim 4
Independent Claim
157 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent teeth of the laminations, said method being characterized by: circumferentially squeezing the heads of the T-shaped teeth on a plurality of the endmost laminations at both ends of the stack with a force that is progressively less on the inwardly successive laminations to thereby deform the heads of the T-shaped teeth on said inwardly sucessive laminations to a progressively less degree and taperingly enlarge the entrances to the winding receiving slots at both ends of the core.
Claim 5
Independent Claim
157 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent teeth of the laminations, said method being characterized by: circumferentially squeezing the heads of the T-shaped teeth on a plurality of the endmost laminations at both ends of the stack with a force that is progressively less on the inwardly successive laminations to thereby deform the heads of the T-shaped teeth on said inwardly sucessive laminations to a progressively less degree and taperingly enlarge the entrances to the winding receiving slots at both ends of the core.
Claim 6
Dependent Claim
48 words
The method of claim 3, further characterized in that said deformation of the heads of the T-shaped teeth is performed with a tool that has wedge-shaped lugs positioned to enter the spaces between the heads of the T-shaped teeth as said tool is forced axially towards the stack.
Claim 7
Dependent Claim
33 words
The method of claim 4, further characterized by covering the ends of the stack of laminations with preformed plastic shields of a size and shape substantially corresponding to that of the endmost laminations.
Claim 8
Dependent Claim
49 words
The method of claim 5, wherein the ends of the heads of those of the T-shaped teeth that are deformed are covered by portions of the plastic shields, and the presence of said portions of the shields is accommodated by said deformation of the heads of the T-shaped teeth.
Claim 9
Dependent Claim
76 words
The method of claim 6, further characterized in that said portions of the shields are interposed between opposite ends of the heads of the teeth and the wedge-shaped lugs of said tool as the latter is forced axially towards the stack, so that the tooth-head deforming force is applied through said portions of the plastic shields and said portions of the plastic shields are driven tightly against the ends of the heads of the T-shaped teeth.
Claim 10
Independent Claim
282 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent teeth of the laminations, said method being characterized by: A. providing preformed plastic shields for the ends of the stack of laminations of a size and shape substantially corresponding to the size and shape of the laminations, but with protective flanges projecting from one face thereof to embrace the T-shaped teeth on the endmost laminations of the stack; B. with one of said shields overlying an end of the stack of laminations with the protective flanges of the shield facing said end of the stack, forcing said shield against the adjacent end of the stack with the protective flanges on the shield covering the edges of The teeth on the endmost laminations; and C. deforming the heads of the T-shaped teeth on a plurality of the endmost laminations of the stack with a circumferentially acting compression force applied through the contiguous protective flange portions and that has progressively less effect on the inwardly successive laminations to thereby axially outwardly taperingly reduce the width of the heads of the teeth and make room for the contiguous protective flanges on the shield, whereby the presence of said protective flanges does not objectively diminish the width of the adjacent entrances to the winding receiving slots.
Claim 11
Independent Claim
282 words
The method of making an electric motor armature, wherein a stack of punched laminations, each of which has a circular row of substantially T-shaped teeth defining its circumference said teeth having heads defined by the cross member of the T, is assembled in aligned relationship on a shaft to form a cylindrical core having circumferentially spaced reentrant winding receiving slots opening to its periphery through narrow axially extending slots formed by the spaces between the heads of the circumferentially adjacent teeth of the laminations, said method being characterized by: A. providing preformed plastic shields for the ends of the stack of laminations of a size and shape substantially corresponding to the size and shape of the laminations, but with protective flanges projecting from one face thereof to embrace the T-shaped teeth on the endmost laminations of the stack; B. with one of said shields overlying an end of the stack of laminations with the protective flanges of the shield facing said end of the stack, forcing said shield against the adjacent end of the stack with the protective flanges on the shield covering the edges of The teeth on the endmost laminations; and C. deforming the heads of the T-shaped teeth on a plurality of the endmost laminations of the stack with a circumferentially acting compression force applied through the contiguous protective flange portions and that has progressively less effect on the inwardly successive laminations to thereby axially outwardly taperingly reduce the width of the heads of the teeth and make room for the contiguous protective flanges on the shield, whereby the presence of said protective flanges does not objectively diminish the width of the adjacent entrances to the winding receiving slots.
Claim 12
Dependent Claim
56 words
The method of claim 8 wherein the shield is forced against the adjacent end of the stack of laminations and the heads of the T-shaped teeth are deformed at the same time by forcing a tool that has wedge-shaped lugs positioned to enter the spaces between the heads of the T-shaped teeth, axially towards the stack.
Claim 13
Dependent Claim
63 words
The method of claim 9, further characterized in that one of said shields is forced against each of the opposite ends of the stack of laminations and said tooth-head deforming operation takes place at each end of the stack, and wherein said operations are performed by axially clamping the stack and the shields at the ends thereof between a pair of said tools.
References Cited (Backward Citations)
US3762041A
Cited
US3768152A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |