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US 4,254,920 AGranted
Air shaft
AssigneeDouble-E Inc.
InventorBruce E. Peterson
Life of this patent
Estimating the term…
Abstract
An expansible shaft including a hollow axially-extending body and operatively coupled core engaging and retracting sections within the body. The core engaging section includes a core engager movable relative to the body in a direction generally perpendicular to the axis of the body and biased towards a core engagement position in which it projects beyond the wall of the body; and the retracting section includes an actuator arranged to overcome the bias and move the core engager radially inwardly from its core engagement position.
Claims18
An expansible shaft comprising:
- a hollow axially-extending cylindrical body;
- a core engaging section within said body;
- a retracting section within said body and spaced axially of said core engaging section;
- and,
- an operating rod extending generally coaxially of said body and coupling said core engaging and said retracting sections,
- said core engaging section including a plurality of circumferentially-spaced core engagers each movable radially relative to said body between a core engagement position in which it projects beyond the cylindrical wall of said body and a withdrawn position radially inwardly of said core engagement position thereof, a cam mounted on said rod and having a camming surface engaging said core engagers, a spring mounted coaxially of said rod and engaging said cam and biasing said cam in one axial direction such that said camming surface urges said core engagers towards said core engagement positions thereof, and a stop within said body restrained against movement relative to said body in the axial direction opposite said one direction and engaging the end of said spring opposite said cam,
- said retracting section including a piston mounted coaxially of said rod and restrained against movement relative to said rod in the axial direction opposite said one direction such that movement of said piston in said direction opposite said one direction moves said rod in said direction opposite said one direction, and a sealing plate mounted coaxially of said rod such that said rod is movable axially relative to said sealing plate and said sealing plate is restrained against axial movement relative to said body in said one direction, and
- said operating rod defining an internal conduit providing for flow of fluid under pressure to a port axially intermediate the piston and sealing plate of said retracting section, said rod being coupled to said piston and said cam such that said fluid under pressure forces said piston in said axial direction opposite said one direction against the bias of said spring of said core engaging section thereby moving said rod and said cam in said direction opposite said one direction.
5 more elements
In an expansible shaft of the type in which a shaft engager projects through an opening in an axially-extending wall of an axially-extending body and is movable relative to the body in directions generally perpendicular to the axis of the body, at least a portion of said shaft engager being circular in cross-section transverse to the direction of movement thereof relative to said body, that improvement comprising:
- an annular seal having an inner annular portion surrounding and sealing engaging the periphery of the circular in-cross section portion of said shaft engager, an outer annular portion sealingly engaging the surrounding portion of said body, and an intermediate annular portion of elastomeric material attached to each of the inner and outer annular portions, said inner and outer annular portions being restrained against movement in said directions generally perpendicular to the axis of said body such that when said shaft engager is moved relative to said body in one of said directions, said seal permits such movement and simultaneously exerts on such shaft engager force tending to move said shaft engager in the opposite direction.
An expansible shaft comprising:
- a hollow cylindrical body of substantially uniform diameter throughout its length;
- a plurality of axially-spaced core engaging sections within said body;
- a plurality of axially-spaced retracting sections within said body;
- and,
- an operating rod extending generally coaxially, of, said body and coupling said core engaging and said retracting sections,
- each of said core engaging sections including a plurality of circumferentially-spaced core engagers each extending radially through said body and radially movable between a core engagement position in which it projects beyond the cylindrical wall of said body and a withdrawn position radially inwardly of said core engagement position thereof, a cam mounted on said rod and having a generally frusto-conical camming surface engaging said core engagers, a spring mounted coaxially of said rod and engaging one end of said cam and biasing said cam in one axial direction such that said camming surface urges said core engagers towards said core engagement positions thereof, and a stop within said body restrained against movement relative to said body in the axial direction opposite said one direction and engaging the end of said spring opposite said cam, and
- each of said retracting sections including a piston mounted coaxially of said rod with its periphery in sliding sealing engagement with the interior cylindrical wall of said body, and a sealing plate mounted coaxially of said rod in sliding sealing engagement with the outer surface of said rod end in sealing engagement with said interior cylindrical wall and restrained against axial movement relative to said body in said one direction, and
- said operating rod defining an internal conduit providing for flow of fluid under pressure to a respective port axially intermediate the piston and sealing plate of each of said retracting sections, and being coupled to said pistons and said cams such that said fluid under pressure forces each of said pistons in said axial direction opposite said one direction, against the bias of said spring of said core engaging section thereof.
5 more elements
Dependencies are inferred from the claim text.