US3693035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double insulated field mounting for universal motor
Assignee: Black and Decker Corp
•
Filing: 1970-09-15
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Granted: 1972-09-19
•
Expires: 1990-09-15
Abstract
Abstract A double insulated heavy duty electric power tool having a metal housing for resisting shock impacts and vibration, and a universal electric motor mounted in the housing. The motor includes a field mounted in the housing with an insulating barrier between the field and the housing. A plurality of insulated bolts secure the field to the housing and a pair of insulating washers associated with each of the bolts maintain a space between the field and the bolts during the after assembly.
Inventors
- 👤 Erich Ostwald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:19
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/12; H02K1/18; H02K1/185; H02K7/00; H02K7/14; H02K7/145
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
150 words
A double insulated field mounting assembly for an electric motor enclosed in a metal housing comprising a universal electric motor field including a field core and a plurality of wound field coils; a metal housing having a bore receiving said field core; an insulating barrier interposed between said field core and said housing; a plurality of bolts extending from one end of said field core into said housing adjacent the opposite end of said field core securing said field to said housing; a plurality of first insulating washers separately surrounding each of said bolts individually and extending into a bore in said one end of said field; a plurality of second insulating washers separately surrounding each of said bolts individually and extending into a bore at said opposite end of said field core; said first and second washers cooperating to pilot said bolts in spaced relation to said field core.
Claim 2
Dependent Claim
150 words
A double insulated field mounting assembly for an electric motor enclosed in a metal housing comprising a universal electric motor field including a field core and a plurality of wound field coils; a metal housing having a bore receiving said field core; an insulating barrier interposed between said field core and said housing; a plurality of bolts extending from one end of said field core into said housing adjacent the opposite end of said field core securing said field to said housing; a plurality of first insulating washers separately surrounding each of said bolts individually and extending into a bore in said one end of said field; a plurality of second insulating washers separately surrounding each of said bolts individually and extending into a bore at said opposite end of said field core; said first and second washers cooperating to pilot said bolts in spaced relation to said field core.
Claim 3
Dependent Claim
37 words
The assembly claimed in claim 1 wherein said field core is provided with bores through which said bolts extend and wherein said bores of said first and second washers comprise enlarged portions coaxial with said bolt bores.
Claim 4
Dependent Claim
17 words
The assembly claimed in claim 2 wherein an insulating sleeve is disposed around each of said bolts.
Claim 5
Dependent Claim
24 words
The assembly claimed in claim 2 wherein said housing includes a plurality of bores, said bolts extending into and being secured to said bores.
Claim 6
Dependent Claim
24 words
The assembly claimed in claim 4 wherein each of said second insulating washers includes an axially extending portion mounted in one of said bores.
Claim 7
Dependent Claim
27 words
The assembly claimed in claim 2 wherein each of said first insulating washers includes a shoulder portion of enlarged diameter which overlies said field around said bolt.
Claim 8
Dependent Claim
25 words
The assembly claimed in claim 6 wherein each of said second insulating washers includes an axially extending portion mounted in a bore in said housing.
Claim 9
Dependent Claim
106 words
A double insulated heavy duty electric power tool comprising a metal housing for resisting shock impacts and vibration; and a universal electric motor, said motor including a field core mounted in said housing; an insulating barrier between said field core and said housing; a plurality of bolts securing said field core to said housing; a pair of insulating washers associated with each of said bolts, said pair of washers being disposed between said bolts and said field so as to maintain a space therebetween during and after assembly said bolts extending through bores in said field, said washers being mounted in enlarged portions of said bores.
Claim 10
Dependent Claim
106 words
A double insulated heavy duty electric power tool comprising a metal housing for resisting shock impacts and vibration; and a universal electric motor, said motor including a field core mounted in said housing; an insulating barrier between said field core and said housing; a plurality of bolts securing said field core to said housing; a pair of insulating washers associated with each of said bolts, said pair of washers being disposed between said bolts and said field so as to maintain a space therebetween during and after assembly said bolts extending through bores in said field, said washers being mounted in enlarged portions of said bores.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |