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US 5,918,512 AGranted
Replaceable bit screwdriver assembly
AssigneeG. Lyle Habermehl
InventorsG. Lyle Habermehl, Paul Towsend Scherer
Life of this patent
Estimating the term…
Abstract
An improved screwdriver in which a replacement bit is removably secured to a mandrel by the bit being axially slidable in an axial socket in the end of the mandrel. The bit is movable from a position coaxially aligned with the socket to a position out of alignment therefrom, to assist in the engagement and driving of misaligned screws. A resilient split-ring which serves to retain the bit in the socket is carried by and replaceable with the bit. With each new bit a new split-ring is also provided.
Claims20
A screwdriver comprising a mandrel elongated along and rotatable about a longitudinal mandrel axis, the mandrel having at a forward end a socket extending from socket opening at the forward end of the mandrel rearwardly along the mandrel axis to rearward end characterized by:
- the socket having a forward section polygonally shaped in cross-section, an enlarged diameter portion spaced rearwardly from the forward section, and a forwardly and axially directed socket stop surface spaced rearwardly from the enlarged diameter portion,
- a replaceable bit extending along a bit axis from a forward bit end to a rearward bit end, generally coaxially removably received in the socket,
- the bit having a polygonal body portion polygonally shaped in cross-section complementary to the polygonally shaped forward section of the socket for transfer of rotational forces from the socket to the bit, a rearward bit portion rearward of the polygonal body portion, a rearwardly and axially directed bit stop surface spaced rearwardly from the rearward bit portion, and an inwardly extending annular groove about the bit defining a reduced diameter portion intermediate the polygonal body portion and the rearward bit portion,
- wherein with the bit urged fully rearwardly into the socket:
- (a) the rearward bit portion locates within the enlarged ditmeter portion for lateral movement therein;
- (b) the bit stop surface engages the socket stop surface to transfer between the bit and the mandrel substantially all compressive forces acting generally parallel to the mandrel axis between the bit and the mandrel yet permitting lateral sliding movement of the bit stop surface on the socket stop surface relative to the mandrel axis in response to compressive forces acting generally normal to the mandrel axis between the bit and mandrel;
- (c) the polygonal body portion locates within the forward section for lateral movement therein with engagement between surfaces of the polygonal body portion and the forward section of the socket preventing inclination of the bit axis relative the mandrel axis beyond a maximum angle of inclination in any direction;
- (d) the forward end of the bit extends from the socket opening for driving a screw into a work piece;
- (e) other than engagement between the socket stop surface and the bit stop surface, the rearward bit portion is spaced laterally out of contact with the socket rearward of the reduced diameter portion of the bit;
- and
- (f) the bit stop surface is laterally slidable on the socket stop surface from any position thereon, in response to compressive forces acting generally normal to the mandrel axis between the bit and the mandrel, to positions in which the bit axis assumes the maximum angle of orientation in any direction and contact between the polygonal body portion and the forward section of the socket transfers therebetween substantially all compressive forces between the bit and the mandrel acting generally normal to the mandrel axis.
8 more elements
A screwdriver comprising a mandrel elongated along and rotatable about a longitudinal mandrel axis, the mandrel having at a forward end a socket extending from a socket opening at the forward end of the mandrel rearwardly along the mandrel axis to a rearward end characterized by:
- the socket having a forward section polygonally shaped in cross-section, an enlarged diameter portion spaced rearwardly from the forward section, and a forwardly and axially directed socket stop surface spaced rearwardly from the enlarged diameter portion,
- a replaceable bit extending along a bit axis front a forward bit end to a rearward bit end, generally coaxially removably received in the socket,
- the bit having a polygonal body portion polygonally shaped in cross-section complementary to the polygonally shaped forward section of the socket for transfer of rotational forces from the socket to the bit, a rearward bit portion rearward of the polygonal body portion, a rearwardly and axially directed bit stop surface spaced rearwardly from the rearward bit portion, and an inwardly extending annular groove about the bit defining a reduced diameter portion intermediate the polygonal body portion and the rearward bit portion,
- wherein with the bit urged fully rearwardly into the socket:
- (a) the rearward bit portion locates within the enlarged diameter portion for lateral movement therein;
- (b) the bit stop surface engages the socket stop surface to transfer between the bit and the mandrel substantially all compressive forces acting generally parallel to the mandrel axis between the bit and the mandrel yet permitting lateral sliding movement of the bit stop surface on the socket stop surface relative to the mandrel axis;
- (c) the polygonal body portion locates within the forward section for lateral movement therein with engagement between surfaces of the polygonal body portion and the forward section of the socket preventing inclination of the bit axis relative the mandrel axis beyond a maximum angle of inclination in any direction and transferring between surfaces of the polygonal body portion and the forward section of the socket substantially all compressive forces between the bit and the mandrel acting generally normal to the mandrel axis,
- (d) the forward end of the bit extends from the socket opening for driving a screw into a work piece;
- (e) other than engagement between the socket stop surface and the bit stop surface, the rearward bit portion is spaced laterally out of contact with the socket rearward of the reduced diameter portion of the bit;
- and
- (f) the bit stop surface laterally slidable on the socket stop surface to positions in which the polygonal body portion and the forward section of the socket engage and prevent inclination of the bit axis relative the mandrel axis beyond the maximum angle of inclination in any direction.
8 more elements
A screwdriver comprising a mandrel elongated along and rotatable about a longitudinal mandrel axis, the mandrel having at a forward end a socket extending from a socket opening at the forward end of the mandrel rearwardly along the mandrel axis to a rearward end characterized by:
- the socket having a forward section polygonally shaped in cross-section, an enlarged diameter portion spaced rearwardly from the forward section, and a forwardly and axially directed socket stop surface spaced rearwardly from the enlarged diameter portion,
- a replaceable bit extending along a bit axis from a forward bit end to a rearward bit end, generally coaxially removably received in the socket,
- the bit having a polygonal body portion polygonally shaped in cross-section complementary to the polygonally shaped forward section of the socket for transfer of rotational forces from the socket to the bit, a rearward bit portion rearward of the polygonal body portion, a rearwardly and axially directed bit stop surface spaced rearwardly from the rearward bit portion, and an inwardly extending annular groove about the bit defining a reduced diameter portion intermediate the polygonal body portion and the rearward bit portion,
- wherein with the bit urged fully rearwardly into the socket:
- (a) the rearward bit portion locates within the enlarged diameter portion for lateral movement therein;
- (b) the bit stop surface engages the socket stop surface to transfer between the bit and the mandrel substantially all compressive forces acting generally parallel to the mandrel axis between the bit and the mandrel yet permitting lateral sliding movement of the bit stop surface on the socket stop surface relative to the mandrel axis;
- (c) the polygonal body portion locates within the forward section for lateral movement therein with engagement between surfaces of the polygonal body portion and the forward section of the socket preventing inclination of the bit axis relative the mandrel axis beyond a maximum angle of inclination in any direction;
- (d) the forward end of the bit extends from the socket opening for driving a screw into a work piece;
- (e) other than engagement between the socket stop surface and the bit stop surface, the rearward bit portion is spaced laterally out of contact with the socket rearward of the reduced diameter portion of the bit;
- and
- (f) engagement between the bit stop surface and the socket stop surface facilitates lateral sliding movement of the bit stop surface on the socket stop surface such that compressive forces between the bit and the mandrel acting generally normal to the mandrel axis are substantially transferred forward of the reduced diameter portion between the polygonal body portion and the forward portion of the socket,
- wherein the socket stop surface is disposed at an angle relative the mandrel axis with the socket stop surface extending radially inwardly towards the mandrel axis and rearwardly towards the rearward end of the socket.
9 more elements
Dependencies are inferred from the claim text.