US3696412A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and means for indicating tension
Assignee: JSJ CORPORATION-MICHIGAN
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Filing: 1970-10-19
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Granted: 1972-10-03
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Expires: 1990-10-19
Abstract
Abstract In a method and means for indicating tension on bolts, screws and the like, a plastic member of flowable material having a plurality of relatively thin copper wires embedded along each edge is utilized. The member has an annular cutout portion permitting it to be inserted between any two bearing surfaces of a threaded fastening joint with the bolt passing through the cutout portion. When the point is tightened to pre-load below yield, the plastic material flows or is extruded until the joint contacts the wire. Subsequent tightening to the desired minimum proof load will shear the wires and material to indicate that minimum proof load has been reached. The plastic strip material also serves as a lubricant to reduce the amount of torque required to reach minimum proof load and a portion is extruded into the core of the joint to act as a lock and seal. In one embodiment, the wires form a pair of leads which may be connected in an electric circuit so that when the joint is tightened to pre-load below the plastic range, there is sufficient extrusion of the plastic material to establish electrical contact between the joint and edge wires to close the electrical circuit, activating an electrical signal to indicate that pre-load has been reached.
Inventors
- 👤 Roger I Swanson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:08
CPC Classifications
G; G01; G01L; G01L5/00; G01L5/24; G01L5/243; F; F16; F16B; F16B31/00; F16B31/02; F16B31/028
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
15 words
The method according to claim 1 wherein said means embedded along each edge is wire-like.
Claim 2
Dependent Claim
15 words
The method according to claim 1 wherein said means embedded along each edge is metallic.
Claim 3
Dependent Claim
12 words
The method according to claim 2 wherein said wire-like means is metallic.
Claim 4
Dependent Claim
71 words
The method according to claim 4 wherein said metallic wire-like means is connected to an electric circuit having an electric source and signal so that when said joint is tightened to a predetermined tensile load of less magnitude than that required to shear said tab, said flowable material is partially deformed and extruded to establish electrical continuity between said metallic means and joint closing said electric circuit to actuate said signal.
Claim 5
Dependent Claim
71 words
The method according to claim 1 wherein said means embedded along each edge is of sufficient hardness in relation to the strength of said joint to permit said joint to be tightened to minimum proof load prior to shear of the tab and sufficiently soft with relation to the strength of said joint to permit complete shearing of the tab prior to the joint being tightened to its ultimate breading point.
Claim 6
Dependent Claim
28 words
The method according to claim 6 wherein a plurality of said tabs are collated into a continuous strip to facilitate mass production and reduce installation time and handling.
Claim 7
Dependent Claim
73 words
The method according to claim 6 wherein one of said bearing surfaces is characterized as having an internal and external chamfer to permit deformation and extrusion of said material and metallic means inwardly around the core of said joint and outwardly away from the fastener, said inwardly extruding portion forming a bond to restrain said joint from rotation should said joint loosen, and further forming a seal to weatherproof said joint after tightening.
Claim 8
Dependent Claim
16 words
The method according to claim 8 wherein said one bearing surface is formed on a nut.
Claim 9
Dependent Claim
18 words
The method according to claim 8 wherein said one bearing surface is formed on a bolt or screw.
Claim 10
Dependent Claim
72 words
The method according to claim 8 wherein said one bearing surface is formed on a washer. 12. The method according to claim 8 wherein said internal chamfer is of less angular magnitude than said external chamfer, and said flowable material provides a lubricant in said joint reducing the amount of torque required to tighten said joint to shear at which point the torque increases due to the increased friction in the joint.
Claim 11
Dependent Claim
26 words
The method according to claim 8 wherein a fastening element means is collated onto each tab in said strip to further reduce handling and installation time.
Claim 12
Dependent Claim
19 words
The method according to claim 13 wherein said element means is comprised of a plurality of screws or bolts.
Claim 13
Dependent Claim
17 words
The method according to claim 13 wherein said element means is comprised of a plurality of nuts.
Claim 14
Dependent Claim
152 words
The method according to claim 13 wherein said element means is comprised of a plurality of washers. 17. A fastener construction comprising, in combination: at least one member with an opening and a fastener element including a shank extending through said opening; a shoulder-like means associated with said shank, said member and shoulder-like means providing two opposed bearing surfaces; a tab of flowable material having means of substantially gReater hardness than said material embedded along each edge, and means defining a cutout portion through which said shank is extended so that when said tab is positioned between two bearing surfaces in said fastener construction with a portion of said embedded means aligned between said bearing surfaces, and said fastener construction is tightened to a predetermined load, the tab will become deformed and extruded at said predetermined load, to completely shear the material and embedded means when said predetermined load has been reached.
Claim 15
Dependent Claim
15 words
The combination according to claim 17 wherein said means embedded along each edge is wire-like.
Claim 16
Dependent Claim
15 words
The combination according to claim 17 wherein said means embedded along each edge is metallic.
Claim 17
Dependent Claim
12 words
The combination according to claim 28 wherein said wire-like means is metallic.
Claim 18
Dependent Claim
69 words
The combination according to claim 17 wherein said means embedded along each edge is of sufficient hardness in relation to the strength of said fastener construction to permit said fastener construction to be tightened to minimum proof load prior to shear and sufficiently soft with relation to the strength of said construction to permit complete shearing of said tab prior to said construction being tightened to its breaking point.
Claim 19
Dependent Claim
78 words
The combination according to claim 20 wherein said metallic wire-like means is comprised of a malleable electric conducting wire connected to an electric circuit having an electric source and signal so that when said fastener construction is tightened to a predetermined tensile load less than minimum proof load, said flowable material will partially deform and extrude to establish electrical continuity between one of said bearing surfaces and said wire to close said circuit and actuate said electric signal.
Claim 20
Dependent Claim
120 words
The combination according to claim 21 wherein one of said bearing surfaces in abutment with said tab is characterized as having an internal and external chamfer to permit extrusion of said material and metallic means inwardly around the core of said fastener construction and outwardly away from the fastener construction, said inwardly extruded portion forming a bond to restrain said fastener construction from rotation should said construction loosen, and further forming a seal to weatherproof said construction. 24. The combination according to claim 23 wherein said internal chamfer is of less angular magnitude than said external chamfer and said flowable material provides a lubricant in said fastener construction to reduce the amount of torque required to tighten said fastener construction.
Claim 21
Dependent Claim
33 words
The combination according to claim 17 wherein said shank includes a head, and one of said bearing surfaces between which said tab is positioned is formed by the head portion of said shank.
Claim 22
Dependent Claim
27 words
The combination according to claim 17 wherein one of said bearing surfaces between which said tab is positioned is formed by a nut threadable on said shank.
Claim 23
Dependent Claim
23 words
The combination according to claim 17 wherein one of said bearing surfaces between which said tab is positioned is formed by a washer.
Claim 24
Dependent Claim
63 words
The combination according to claim 17 wherein one of said bearing surfaces between which said tab is positioned is formed by said one member. 29. The combination according to claim 17 wherein said fastener element is adapted to tighten said fastener construction, and the bearing area of said opposed bearing surfaces is substantially equal to the cross-sectional bearing area of said fastener element.
Claim 25
Dependent Claim
77 words
The combination according to claim 29 wherein one of said bearing surfaces in abutment with said tab is characterized as having an internal and external chamfer to permit extrusion of said material and metallic means inwardly around the core of said fastener construction and outwardly away from the fastener construction, said inwardly extruded portion forming a bond to restrain said fastener construction from rotation should said construction loosen, and further forming a seal to weatherproof said constructiOn.
Claim 26
Dependent Claim
42 words
The combination according to claim 30 wherein said internal chamfer is of less angular magnitude than said external chamfer and said flowable material provides a lubricant in said fastener construction to reduce the amount of torque required to tighten said fastener construction.
Claim 27
Dependent Claim
147 words
A fastener construction comprising, in combination: at least one member with an opening and a fastener element including a shank extending through said opening; a shoulder-like means associated with said shank, said member and shoulder-like means providing two opposed bearing surfaces: a continuous strip of flowable material having means of substantially greater hardness than said material embedded along each edge, and means defining a plurality of openings spaced along said strip, said openings permitting passage of a threaded member therethrough so that when one of said openings is positioned between two bearing surfaces in a fastener construction with a portion of said embedded means aligned between said bearing surfaces, and said fastener construction is tightened to a predetermined tensile load, the strip will become deformed and extruded at a predetermined load to completely shear the material and embedded means when said predetermined tensile load has been reached.
Claim 28
Dependent Claim
72 words
The combination according to claim 32 wherein said embedded means is of sufficient hardness in relation to the strength of said fastener construction to permit said fastener construction to be tightened to minimum proof load prior to shear of the strip and sufficiently soft with relation to the strength of said fastener construction to permit complete shearing of the strip prior to the fastener construction being tightened to its ultimate breaking point.
Claim 29
Dependent Claim
82 words
The combination according to claim 33 wherein said embedded means along each edge is comprised of a malleable metallic wire-like means connected to an electric circuit having an electric source and signal so that when said fastener construction is tightened to a predetermined tensile load of less magnitude than that required to shear said tab, said flowable material is partially deformed and extruded to establish electrical continuity between said metallic means and fastener construction closing said electric circuit to actuate said signal.
Claim 30
Dependent Claim
38 words
The combination according to claim 32 wherein a plurality of fastening element means are collated onto said strip to further reduce handling and installation time, each of said fastening element means being aligned with one of said openings.
Claim 31
Dependent Claim
19 words
The combination according to claim 35 wherein said element means is comprised of a plurality of screws or bolts.
Claim 32
Dependent Claim
17 words
The combination according to claim 35 wherein said element means is comprised of a plurality of nuts.
Claim 33
Dependent Claim
102 words
The combination according to claim 35 wherein said element means is comprised of a plurality of washers. 39. A fastener construction having at least two bearing surfaces and a tension indicating device comprising at least one element including metallic means embedded in a flowable solid material, said element being positioned between said two bearing surfaces in said fastener construction so that when said fastener construction is tightened to a predetermined tensile load said element including said metallic means will become sufficiently deformed and extruded to completely shear said element including said metallic means, thereby indicating that said predetermined load has been reached.
Claim 34
Dependent Claim
12 words
The construction according to claim 39 wherein said metallic means is wire-like.
Claim 35
Dependent Claim
57 words
The construction according to claim 39 wherein said flowable solid material is deformed away from said metallic means embedded therein at a second predetermined tensile load less than said first predetermined tensile load whereby at least one of said two bearing surfaces are in physical contact with said metallic means when said second tensile load is reached.
Claim 36
Dependent Claim
17 words
The construction according to claim 41 wherein said metallic means is comprised of an electRical conducting material.
Claim 37
Independent Claim
105 words
A method for indicating load tension in a threaded fastener joint comprising the steps of: providing a tab of flowable material having metallic means of substantially greater hardness than said material embedded along each edge and means defining a cutout to permit passage of a threaded member therethrough; positioning said tab between two bearing surfaces in said joint so that a portion of said embedded means is between said bearing surfaces; and tightening the threaded fastener to apply a tensile load to the joint of sufficient magnitude to partially deform and extrude said flowable material to establish electrical continuity between said metallic means and joint.
Claim 38
Dependent Claim
54 words
A method according to claim 43 wherein said metallic means is wire-like and connected to an electric circuit having an electric source and signal so that when said joint is tightened to a predetermined tensile load to establish electrical continuity between said wire-like means and joint, said electric circuit closes to actuate said signal.
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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) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |