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US 4,399,166 AGranted
Friction lock for threads
AssigneeThe Oakland Corporation
InventorRichard B. Wallace
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AssigneeThe Oakland Corporation
InventorRichard B. Wallace
Estimating the term…
Method and apparatus for providing friction producing ring patches on externally threaded fasteners which comprises depositing a fluid wetting agent on a predetermined thread area, supplying thermoplastic resin powder particles to the fluid deposit to form deposits of fluid mixtures, flash heating the mixture deposit to fuse resin particles only at the surfaces to produce a non-tacky skin, accumulating agglomerations of the fasteners and retaining them for an interval sufficient to permit at least substantially complete drying of the fluid mixture deposits to form substantially solid cohesive deposits of discrete resin particles, mass heating the fasteners to fuse the discrete resin particles into continuous fluid deposits and finally cooling the fasteners in separated condition to set the fused resin deposits into solid continuous resin deposits fused to the thread surfaces of the fasteners.
The method of preparing a multiplicity of externally threaded fasteners for subsequent substantially mass heat treatment in an energy conserving operation in which substantially solid coherent deposits consisting essentially of discrete thermoplastic resin powder particles are fused, which comprises continuously advancing a series of fasteners with their axes vertical, sequentially forming deposits consisting essentially of a viscous fluid wetting agent of predetermined size and shape in the thread grooves of the fasteners as they advance, thereafter supplying thermoplastic resin powder to the surfaces of the deposits of fluid wetting agent to penetrate and form therewith fluid mixture slurry deposits substantially of the aforesaid size and shape which in cross-section fill the bottoms of the thread grooves, and extend nearly to but not beyond the thread crests, sequentially fusing the resin powder particles at the surfaces of the deposits and eliminating the fluid wetting agent thereat as the fasteners continue to advance without heating the deposits or fasteners sufficiently to produce a fused bond between the deposits and thread surfaces, cooling the deposits to cause the fused surface particles to form a non-tacky skin over the deposits, accumulating the fasteners in agglomerated condition and retaining them until enough have been accumulated for economical mass heat treatment to fuse the resin to the thread surface.
The method of making friction threaded fasteners which comprises continuously advancing a series of fasteners with their axes vertical, sequentially forming deposits consisting essentially of a viscous fluid wetting agent of predetermined size and shape in the thread grooves of the fasteners as they advance, thereafter sequentially supplying thermoplastic resin powder to the surfaces of the deposits of fluid wetting agent to form therewith fluid slurry mixture deposits of the aforesaid size and shape which in cross-section fill the bottoms of the thread grooves and extend nearly to but not beyond the thread crests, fusing the resin powder particles at the surfaces of the mixture deposits as the fasteners continue to advance and simultaneously substantially eliminating the fluid wetting agent from the mixture, cooling the deposits to cause the fused surface particles to form a non-tacky skin over the deposits, accumulating the fasteners in agglomerated condition and retaining them until the mixture deposits have dried to form substantially solid cohesive deposits of discrete powder particles, and fusing the solid deposits of discrete resin particles comprising substantially simultaneously heating a quantity of fasteners.
Apparatus for making friction threaded fasteners which comprises a first conveyor for continuously advancing a series of externally threaded fasteners with their axes vertical, applicator means at the side of the path of advance of the fasteners for applying deposits of a fluid wetting agent to extend around the threaded portions of the fasteners, powder supply means at the side of the path of advance of the fasteners for supplying a thermoplastic resin powder to the deposits of wetting agent as the fasteners continue to advance to form annular deposits of a fluid mixture of wetting agent and resin powder on the fasteners, flash heating means at the side of the path of advance of the fasteners to fuse resin particles only at and adjacent the surfaces of the deposits of the mixture of wetting agent and powder to convert the exposed surfaces of the deposits to a dry, non-tacky condition without fusing all particles within the deposits to each other or to the thread surfaces, a second horizontal conveyor for receiving and advancing a mass of the fasteners after the fluid mixture deposit has at least substantially dried to leave a substantially solid cohesive deposit of discrete resin particles, a heating oven through which the fasteners advance to fuse the discrete particles into a continuous fluid mass, means for cooling the fasteners to form the deposits into solid continuous masses fused to the thread surfaces of the fasteners comprising a cooling bath into which the fasteners are deposited from the conveyor in separated condition, and brush means for brushing the fasteners in separated condition from the second conveyor into the bath.
The method of making friction fasteners which comprises advancing a multiplicity of externally threaded fasteners continuously in a series and forming thereon as they advance deposits of a fluid slurry mixture containing discrete thermoplastic resin particles in a fluid carrier, sequentially treating the fasteners as they advance to convert the exposed surfaces of the deposits to a dry, non-tacky condition, agglomerating a mass of the fasteners, retaining the mass of fasteners until the liquid carrier is substantially eliminated to leave a substantially solid deposit formed of discrete thermoplastic particles, and subjecting them to an essentially batch type heat treatment to fuse the discrete particles into an essentially continuous fluid deposit, and abruptly cooling the fasteners to solidify the fluid resin.
The method of making friction threaded fasteners which comprises continuously advancing a series of externally threaded fasteners, sequentially forming in the thread grooves of the fasteners as they advance fluid deposits of a mixture of a wetting agent and a powder consisting of discrete thermoplastic resin particles, sequentially treating the fasteners as they advance to convert the exposed surfaces of the deposits to a dry, non-tacky condition, thereafter accumulating the fasteners in agglomerated condition and retaining them until the wetting agent is substantially completely eliminated to leave the individual deposits in the form of substantially solid cohesive bodies of at least partly discrete resin particles, fusing the resin particle deposits into continuous fluid condition by substantially simultaneously heating a quantity of the accumulated fasteners to a temperature sufficient to fuse the resin particles, and finally abruptly chilling the fused resin into continuous solid deposits fused to the adjacent thread surfaces.
Dependencies are inferred from the claim text.