Fatigue Technology, Inc.

Darryl E Quincey

Eric T Easterbrook

Leonard F Reid

Charles M Copple

Michael A Landy

Roger T Bolstad

Louis A Champoux

Richard Z Jarzebowicz

William B Walsh

Louis A Champoux, Deceased

Charles A Copple

A circular opening (54) is formed in a wall (12). A tubular shank (42) of a nut mounting unit (40) is inserted into the opening (54). The unit (40) is moved endwise to place a nut cage base (46) against the wall (12). A split sleeve (82) is installed on a small diameter portion (90) of a mandrel (M). The mandrel (M) and sleeve (82) are inserted into the tubular shank (42) from the side of the wall (12) opposite the nut cage (44). The mandrel (M) is then retracted to successfully move increasing and maximum diameter portions (90, 92) of the mandrel (M) through the split sleeve (82). The mandrel portions (92, 94) exert a radially outwardly expanding force on the split sleeve (82). The split sleeve (82) in turn imposes a radially outwardly expanding force on the tubular shank (42). This causes a plastic deformation of the tubular shank (42), creating a tight interference fit between the tubular shake (42) and the sidewall of the opening (54). In this manner, the unit (40) is firmly secured to the wall (12). Next, a nut (20) is inserted into the nut cage (44), between end stops (56, 58). A retainer spring (68) is placed over the base (24) of the nut (20), and is compressed an amount sufficient to move side portions (64, 66) together enough that they will fit between cage sidewalls (48, 50). Then, the squeezing force on the retainer spring (68) is released, allowing side portions (64, 66) to move outwardly into openings (60, 62) in the sidewalls (48, 50). In this position the sidewalls (48, 50) restrain sideways movement of the nut. The end stops (56, 58) restrain endwise movement of the nut (20). The inner spring (68) prevents movement of the nut (20) out from the nut cage (44).

Nut cage and mount

An internally lubricated, longitudinally split sleeve is positioned on a small diameter portion a mandrel having a rear end connected to a piston with a puller tool. The rear end of the split sleeve is flared and is against the front end of a tubular sleeve stop which immediately surrounds the mandrel. The puller tool includes a tubular sleeve holder which surrounds the sleeve stop. A forward main portion of the sleeve holder is separated by a pair of longitudinal slots into a pair of elongated fingers. The forward ends of the fingers define a sleeve and mandrel receiving end opening and jaws radially outwardly bounding the opening. The mandrel and sleeve holder are both extended and then the puller tool is moved into alignment with a sleeve and is moved endwise to push the mandrel through the sleeve until the flared end of the sleeve is against the sleeve stop. Then the sleeve holder is retracted. Next, the mandrel and sleeve are inserted into a hole in a workpiece and the tool is moved forwardly until the front ends of the jaws are against the workpiece. Then, the puller tool is operated to retract the mandrel through the sleeve and into the sleeve stop. Retraction of the mandrel moves first an increasing diameter portion of the mandrel and then a maximum diameter portion of the mandrel through the sleeve which radially expands the sleeve and cold expands the material immediately surrounding the hole in the workpiece. After the mandrel is retracted into the sleeve stop, the puller tool is moved away from the workpiece. The jaws of the sleeve holder engage and retain the sleeve so that the sleeve is pulled out from the hole in the workpiece.

Split sleeve cold expansion

A circular opening (48) is formed in a structural wall (12). A tubular shank (28) of a nut mounting grommet (26) is inserted into the opening (48). The grommet (26) is moved endwise to place a shoulder surface (34) on the base of a nut mounting cup (30) against the wall (12). A split sleeve (54) is installed on a small diameter portion (62) of a mandrel (52) and the mandrel and sleeve (52, 54) are inserted into the tubular shank (28) from the side of the wall (12) opposite the nut receiving cup (30). The mandrel (52) is then retracted to successively move increasing and maximum diameter portions (64, 66) of the mandrel (52) through the split sleeve (54). The mandrel portions (64, 66) exert a radially outwardly expanding force on the split sleeve (54). The split sleeve (54) in turn imposes a radially outwardly expanding force on the tubular shank ( 28). This causes a plastic deformation of the tubular shank (28), creating a tight interference fit between the tubular shank (28) and the sidewall of the opening (48). In this manner, the grommet (26) is firmly secured to the wall (12). Next, a nut (24) is inserted into the cup (30) with its threaded central opening (18) in alignment with the passageway through the tubular shank (28). The sidewall of the cup (30) is deformed, to place portions of a lip (46) endwise of the nut (20), in the path of removal of the nut (20) from the cup (30). The sidewall of the cup (30) includes wrench flats (98) outwardly bounding wrench flats (100) on the nut (20).

Method of installing a nut mounting grommet

Nut mounting grommet

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Seattle, WA, United States of America

Darryl E Quincey