US4578852A
Expired / Lapsed
US
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Methods of assembling field subassemblies
Assignee: Black and Decker Inc
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Filing: 1984-07-31
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Granted: 1986-04-01
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Expires: 2004-07-31
Abstract
Abstract A field subassembly is assembled by positioning two coil supports adjacent respective core end faces of a ferromagnetic core. The core-engaging surfaces of the coil supports and the core end faces have respective surfaces which are uninterrupted by projections. During the assembly of the field, fasteners are pushed into the respective coil supports and the core such that the fasteners engage mounting holes in the coil support with a press-fit. After the field is wound, a brush holder subassembly is also pressed onto the fasteners and the resultant core subassembly is connected to a field housing by driving the fasteners in a conventional fashion. In the preferred embodiment, the fasteners provide a three-point contact with mounting holes formed in the coil supports and the brush holder subassembly. This enables the fasteners to maintain the coil supports and the brush holder subassembly in alignment with the core while shearing a minimum of material from the coil supports and brush holder subassembly when the fasteners are pushed into their respective mounting holes. Then, the same fasteners remain with the subassembly to connect the field subassembly to the field housing.
Inventors
- 👤 William D. Sauerwein
- 👤 John E. Dibbern, Jr.
- 👤 Frank J. O'Hara
- 👤 Robert G. Moores, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:48
CPC Classifications
H; H02; H02K; H02K3/00; H02K3/46; H02K3/52; H02K3/521; H02K3/522; H02K1/00; H02K1/06; H02K1/12; H02K1/18; H02K1/185; H02K5/00; H02K5/04; H02K5/14; H02K5/143; H02K5/148; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49009; Y10T29/49826; Y10T29/49945
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
118 words
A method of assembling a field subassembly, comprising the steps of: (a) providing a ferromagnetic core defining a longitudinal axis, two through-holes, and first and second axial end faces; (b) providing an insulating member formed of electrically insulating material and having two mounting holes; (c) positioning the insulating member adjacent the first core end face such that the mounting holes are aligned with the core through-holes; (d) providing two elongated fasteners having a cross-sectional dimension smaller than that of the core through-holes but engageable with the insulating member mounting holes in a press-fit; and (e) pushing the fasteners into the core through-holes at the second axial end face, through the core, and into the insulating member mounting holes.
Claim 2
Independent Claim
118 words
A method of assembling a field subassembly, comprising the steps of: (a) providing a ferromagnetic core defining a longitudinal axis, two through-holes, and first and second axial end faces; (b) providing an insulating member formed of electrically insulating material and having two mounting holes; (c) positioning the insulating member adjacent the first core end face such that the mounting holes are aligned with the core through-holes; (d) providing two elongated fasteners having a cross-sectional dimension smaller than that of the core through-holes but engageable with the insulating member mounting holes in a press-fit; and (e) pushing the fasteners into the core through-holes at the second axial end face, through the core, and into the insulating member mounting holes.
Claim 3
Dependent Claim
34 words
The method claimed in claim 1, wherein in the step of pushing the fasteners, the fasteners are inserted into the core and insulating member with a non-rotating axial motion parallel to the core axis.
Claim 4
Dependent Claim
39 words
The method claimed in claim 1, wherein: (a) the fasteners including a threaded portion having a tri-lobular, annular cross-section; (b) the insulating member being formed of molded plastic; and (c) the threaded portion engaging the insulating member mounting hole.
Claim 5
Dependent Claim
57 words
The method claimed in claim 1, wherein: (a) the insulating member being a coil support having a coil supporting portion, and further comprises the steps of: (b) providing a length of field wire; and (c) winding the wire on the core and a corresponding coil supporting portion such that the wire is electrically insulated from the core.
Claim 6
Dependent Claim
48 words
The method claimed in claim 4, wherein: (a) the coil support further including a terminal support portions; and further comprising the steps of: (b) inserting a field terminal in the terminal support portion; and (c) electrically connecting an end of the field wire to a respective field terminal.
Claim 7
Dependent Claim
49 words
The method claimed in claim 5, wherein: (a) the coil support having an external surface; and (b) in the step of pushing the fasteners, the fasteners are inserted into the core and coil support such that a portion of each fastener protrudes from the surface of the coil support.
Claim 8
Dependent Claim
73 words
The method claimed in claim 6, further comprising the steps of: (a) pushing the fasteners axially toward the second core axial end face such that the end of the protruding portions become flush with the surface of the coil support; (b) providing a field housing having mounting apertures formed therein; and (c) attaching the core to the housing by driving the fastener threaded portions into threaded engagement with respective field housing mounting holes.
Claim 9
Independent Claim
179 words
A method of assembling a field for an electric motor-driven device, comprising the steps of: (a) providing a stack of ferromagnetic field laminations defining a central opening, two axial through-holes, and first and second axial end faces; (b) providing two electrically insulating coil supports, each having two mounting holes; (c) providing two elongated fasteners, each having a headed end and a non-headed end, the fasteners having portions adjacent their respective non-headed ends which are engageable in the stack through-holes with a clearance fit and in the coil support mounting holes with a press-fit; (d) positioning one of the coil supports adjacent each stack axial end face such that the respective coil support mounting holes are in registration with the stack through-holes; (e) pressing each fastener axially through a respective coil support mounting hole of one of the coil supports, through one of the corresponding stack through-holes, and into a respective coil support mounting hole of the other coil support; (f) providing a length of field coil wire; and (g) winding the wire about the stack and respective coil supports.
Claim 10
Independent Claim
179 words
A method of assembling a field for an electric motor-driven device, comprising the steps of: (a) providing a stack of ferromagnetic field laminations defining a central opening, two axial through-holes, and first and second axial end faces; (b) providing two electrically insulating coil supports, each having two mounting holes; (c) providing two elongated fasteners, each having a headed end and a non-headed end, the fasteners having portions adjacent their respective non-headed ends which are engageable in the stack through-holes with a clearance fit and in the coil support mounting holes with a press-fit; (d) positioning one of the coil supports adjacent each stack axial end face such that the respective coil support mounting holes are in registration with the stack through-holes; (e) pressing each fastener axially through a respective coil support mounting hole of one of the coil supports, through one of the corresponding stack through-holes, and into a respective coil support mounting hole of the other coil support; (f) providing a length of field coil wire; and (g) winding the wire about the stack and respective coil supports.
Claim 11
Dependent Claim
18 words
The method claimed in claim 8, wherein the fasteners including a threaded portion adjacent the respective non-headed ends.
Claim 12
Dependent Claim
11 words
The method claimed in claim 8, wherein the fasteners being rivets.
Claim 13
Dependent Claim
30 words
The method claimed in claim 8, wherein the fasteners further including alignment means adjacent the respective non-headed ends for maintaining a three-point contact with the respective coil support mounting holes.
Claim 14
Dependent Claim
29 words
The method claimed in claim 11, wherein the alignment means including a threaded portion formed on the fasteners adjacent the respective non-headed ends and having a tri-lobular annular cross-section.
Claim 15
Dependent Claim
82 words
The method claimed in claim 9, wherein: (a) the fasteners further including a shank portion intermediate the headed end and the threaded portion; (b) the threaded portion having an outer diameter greater than that of the shank portion; (c) the coil support further including fastener compensating means operatively associated with the coil support mounting holes for expanding the holes to permit entry of the fastener threaded portion into a respective coil support mounting hole and to contract to engage the fastener shank.
Claim 16
Dependent Claim
25 words
The method claimed in claim 13, wherein the fastener compensating means including a slot formed in the coil supports intersecting the coil support mounting holes.
Claim 17
Dependent Claim
58 words
The method claimed in claim 14, wherein in the step of pressing each fastener into the coil supports and stack, the fasteners are inserted such that the headed end engages the coil support adjacent the second stack axial end face, and the threaded portion extends axially outwardly from the coil support adjacent the first stack axial end face.
Claim 18
Dependent Claim
63 words
The method claimed in claim 15, wherein: (a) two terminal supports being formed on the coil support adjacent the first stack axial end face; and further comprising the steps of: (b) providing two field terminals; (c) inserting a field terminal in each of the field terminal supports; and (d) electrically connecting each end of the field coil wire to a respective field terminal.
Claim 19
Dependent Claim
51 words
The method claimed in claim 16, further comprising the steps of: (a) providing a brush holder subassembly having two mounting holes engageable with the fastener threaded portions with a press-fit; and (b) pressing the brush holder subassembly onto the outwardly extending fastener threaded portions via the brush holder subassembly mounting holes.
Claim 20
Dependent Claim
91 words
The method claimed in claim 17, wherein: (a) the electric motor-driven device including a housing member having two mounting apertures, and further comprising the steps of: (b) axially pushing the fasteners towards the stack second axial end face such that the non-headed ends are flush with the brush holder subassembly; (c) aligning the fasteners with the housing member mounting apertures; and (d) driving the fasteners into threaded engagement with the housing member mounting apertures such that the fastener headed ends engage the coil support adjacent the stack second axial end face.
Claim 21
Dependent Claim
27 words
The method claimed in claim 18, wherein: (a) the electric motor-driven device being a power tool; and (b) the housing member being a power tool field case.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-31 | 1989-09-30 | 1990-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-31 | 1993-09-30 | 1994-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-31 | 1997-09-30 | 1998-04-01 | $7700.00 | Window Closed / Lapsed |