Patent US3736394A successfully refreshed from Google Patents.
US3736394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Condition sensing assembly positioned as washer
Assignee: Individual
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Filing: 1971-09-14
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Granted: 1973-05-29
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Expires: 1991-09-14
Abstract
Abstract A sensing element mounted like a washer having an outer fiber layer bonded to and insulating the flat, circular top surface of an upper metal sheet, which, in cross section, is hook shaped on opposite, outer sides. The other side of the upper metal surface is insulated by a bottom fiber layer. A circular Belville spring washer contacts the bottom fiber layer on one side and a circular metal support structure on the other side. In cross section the support structure has an elongated vertical part extending from the shaft location outward, terminated by a flange which extends further under and to the end of the spring. The hook shaped part ends in the area under the flange. A point on the upper sheet is jointed to a tab to which an electrical lead is soldered. The bottom of the support is sweat soldered to a thin, circular metal sheet, the end of which at one point is jointed to a tab which extends past the top sheet and to which a second electrical lead is soldered. Upon loosening of a nut or bolt with which the invention is used, the spring forces the upper and lower elements apart until the hook shaped part contacts the flange of the support, thereby completing an electrical circuit between the two leads which signals the loose condition.
Inventors
- 👤 D Rumbaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:44
CPC Classifications
H; H01; H01H; H01H35/00; F; F16; F16B; F16B31/00; F16B31/02; F16B31/028; H01H13/00; H01H13/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
259 words
A device for installation with a fastener comprising a first conductive member and a second conductive member normally electrically insulated from each other; said first conductive member having a part on the outer side of said device extending toward the second conductive member, said second conductive member defining an open area through which said extending part moves and then makes electrical contact with said second conductive member, an electric connector for making a signal circuit connected to said extending part of said first conductive member, a second electric connector for making said signal circuit connected to said second conductive member, on a part which is on the outer side of the device and a spring positioned between said first and second conductive members adapted to move them apart when not tightly held by a fastener, said device having a centrally positioned hole for receiving the shank of a fastener, said first conductive member having a flange on the side toward said spring with a vacant area at the side of said flange opposite said spring, said extending part extends past said flange and then back into said vacant area in the general form of a hook, said hook part being in said vacant area when said spring is collapsed while making electrical contact with said flange when said spring moves said members apart, a circular resilient ring positioned to be tightly contacted by said hook part when said first and second conductive members are held tightly by a fastener to seal the inside of said device from surrounding materials.
Claim 2
Independent Claim
259 words
A device for installation with a fastener comprising a first conductive member and a second conductive member normally electrically insulated from each other; said first conductive member having a part on the outer side of said device extending toward the second conductive member, said second conductive member defining an open area through which said extending part moves and then makes electrical contact with said second conductive member, an electric connector for making a signal circuit connected to said extending part of said first conductive member, a second electric connector for making said signal circuit connected to said second conductive member, on a part which is on the outer side of the device and a spring positioned between said first and second conductive members adapted to move them apart when not tightly held by a fastener, said device having a centrally positioned hole for receiving the shank of a fastener, said first conductive member having a flange on the side toward said spring with a vacant area at the side of said flange opposite said spring, said extending part extends past said flange and then back into said vacant area in the general form of a hook, said hook part being in said vacant area when said spring is collapsed while making electrical contact with said flange when said spring moves said members apart, a circular resilient ring positioned to be tightly contacted by said hook part when said first and second conductive members are held tightly by a fastener to seal the inside of said device from surrounding materials.
Claim 3
Dependent Claim
67 words
The device as in claim 1 in which a fiber layer adapted to provide electrical insulation is positioned on one side of said first conductive member and a second fiber layer adapted to provide electrical insulation is positioned on the other side of said first conductive member, said first conductive member being spaced from said central hole and normally supported and electrically insulated by said fiber layers.
Claim 4
Dependent Claim
44 words
The device as in claim 2 in which said second conductive member includes a part located between said flange and said hole which extends past said vacant area and is of sufficient width to provide support to resist the forces of a tightened fastener.
Claim 5
Dependent Claim
24 words
The device as in claim 3 also comprising a lamination of abrasion-resistant material positioned on the outside of the outer of said fiber layers.
Claim 6
Dependent Claim
48 words
The device as in claim 3 in which said first conductive member, said fiber layers, said spring, said flange and said part located between said flange and said hole are all circular, symmetrical around said hole and substantially identical in cross section at all positions around said circle.
Claim 7
Dependent Claim
109 words
The device as in claIm 5 in which one of said electric connectors is connected to the outside of said extending part and the other electric connector is connected to a part of said second conductive member which extends to the outside of said device past said extending part, and in which said device also comprises a circular, resilient ring positioned to be tightly contacted by said hook part when said first and second conductive members are held tightly by a fastener to seal the inside of said device from surrounding material and a lamination of abrasion-resistant material positioned on the outside of the outer of said fiber layers.
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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) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |