Abstract: A screw with a recessed head (3) has a crossing recess (4) formed in a top of the head and consisting of a central region (5) and four grooves (6) extending radially from the central region. Each groove is tapered to reduce width towards an outer conical bottom (9), which defines the groove together with opposite side walls (7, 8) transmitting torque. The bottom connecting outer edges of the side walls has a width ‘A’ larger than width ‘a’ in the widely used standard recesses of the same length ‘M’. The side walls have a radial length ‘B’ smaller than ‘A’, and distance ‘C’ between the intersections of two side walls of different grooves is equal to or larger than the product of 1.5 and ‘A’. One side wall (7) lies in a flat plane in parallel with the screw's axis, and is located forward in a tightening direction of the screw. The conical bottom (9) slanted 5° relative to the axis provides a conical sticking surface.

Abstract: A tool according to the invention includes elements adapted to achieve a primary function of the tool, and further includes a writing element adapted to achieve a writing function. In one example, the tool is a screwdriver, and the writing element comprises a pencil lead that can be extended from the head end of the screwdriver to achieve a writing function, and retracted within the head end of the screwdriver to perform a screwdriving function.

Abstract: A king pin cap tool kit comprises a pair of cap removal tools for removing MACK® truck king pin caps of different diameters and a pair of thread chasers for repairing internal threads in steering knuckle housing bores of corresponding diameters. Each cap removal tool comprises a cylindrical body having a cruciform protrusion extending from one end face and a polygon-shaped recess through the opposite end face to adapt the cap removal tool for driving connection to a conventional pneumatic impact gun. The cruciform protrusion is uniform in its height and includes a pair of intersecting legs that extend fully across the end face in diametrical fashion. A cap removal tool having three intersecting legs is also disclosed. Each thread chaser comprises a cylindrical body having opposite end faces, a threaded peripheral surface, and polygon-shaped axial through hole for receiving a breaker bar or ratchet with extension.

Abstract: An improved fastener system includes a threaded pin and a tool. The pin contains a recess in a threaded end of the pin for receiving the tool, thus holding the pin against rotation during application of a nut on the pin. The recess includes splines extending around a circumference of the recess. A plurality of mating splines are located on an end of the tool for engaging the slots of the recess. The splines are oriented to maximize torsional performance and to balance the shear strength of the pin with the shear strength of the tool. Additionally the ends of the recess splines and a minor diameter of the tool include a matching curved surface to increase torsional strength.

Abstract: Recessed head fasteners are provided with a configuration by which the force applied by the blades of the driver to the recessed wings is applied at the radially outer regions of the wings. The wings of the fastener recess may be provided with torque pads at the outer regions of the wings adapted to engage the outer portions of the driver blades. The torque pads may be defined by relieved regions on the drive walls of the recess wings. The relieved regions are formed to avoid contact with the driver blades. Stabilizing ribs also may be defined at the radially inward regions of the drive walls. A recess engageable driver may include a plurality of radially extending ribs configured to promote engagement of the ribs with the most radially outward regions of the recess drive walls. The driver and the recess are compatible with each other as well as with otherwise corresponding conventional recesses and drivers that do not incorporate the invention.

Abstract: A torque transmitting or coupling arrangement for a fastener drive system or the like, wherein the respective externally configured and internally configured components include a body having an axis in which the body has a modified polygonal cross section defined by a perimeter wall. A polygonal central portion positioned within the perimeter wall has an area less than the area of the modified polygonal cross section. A drive wall which forms a portion of the perimeter wall extends on a plane from a proximal end outwardly from the polygonal central portion to a distal end. A first outer wall forming another portion of the perimeter wall has a proximal end joining the distal end of the drive wall at an angle and a distal end terminating on the perimeter wall. The system includes a fastener driver, a threaded fastener and a forming tool for forming a recess in the fastener.

Abstract: A drill bit for applying torque to a fastener and mounting the fastener to a stud. The fastener has a plurality of support walls and a bore that has an axial length disposed within the fastener. The drill bit includes a shaft, which has an engagement end for abutting the stud. A member is attached to the shaft proximate the engagement end and has a plurality of arms each including a front side for biasing against one of the support walls when the drill bit is rotated. Moreover, when mounting of the fastener on the stud is initiated, the fastener is rotated by the front side of each of the plurality of arms of the member biasing against one of the support walls of the fastener, subsequently, the engagement end of the shaft abuts the stud and is prevented from biasing axially while simultaneously the fastener continues to be progressively mounted on the stud.

Abstract: A screwdriver used for a screw tightener includes at its tip portion a blade having a plurality of flat plate portions to be meshed in a recess formed in a head of a screw. In this screwdriver, each of the flat plate portions has at its tip portion an outer peripheral surface which extends in such a manner as to be converged in the direction toward the tip portion of the screwdriver. The outer peripheral surface of the flat plate portion is formed into an angled shape having a ridge line portion extending in the direction toward the tip portion of the screwdriver.

Abstract: A drive tool for use in driving a fastener having a combination head having slots to accommodate either a flat-blade screwdriver or a Phillips-type screwdriver, the drive tool having both a flat-blade and a Phillips-type blade, and foot portions positioned on each of said flat-blade and said Phillips-type blade for engaging the slots in the combination head. Additionally, a centering tip is provided that fits into the slots of the combination head and allows the drive tool to be guided into proper position by the slots.

Abstract: A theft prevention system is disclosed wherein modified screw heads can be removed by only a specially configured tool. The screw heads have a central polygon groove with at least two grooves projecting outward from the polygon. The screw removal tool is adapted to mate with the polygon groove and the projecting grooves to accomplish removal and tightening of the screw.

Abstract: A new Screw & Driver System for providing a way for releasably securing a driver to the head of a screw such that the driver cannot be lifted straight up and out of the screw. The inventive device includes a screw and a driver therefore. The screw has a head with an hourglass-shaped driver receiving cavity. The hourglass-shaped driver receiving cavity includes a middle section and a pair of opposed wedge-shaped sections extending from the middle section. The pair of opposed wedge-shaped sections have undercut sidewalls. The driver includes a tool element having an hourglass-shaped end wherein the hourglass-shaped end of the tool element has shoulder surfaces which cooperably engage and lockingly mate with the undercut sidewalls of the pair of opposed wedge-shaped sections when the driver and the screw are in working engagement.

Abstract: A self-retaining screwdriver having a plurality of diametrically opposed, radially extending blades on its tip for engagement with corresponding slots of a screw or other fastener, wherein the blades vary radially in thickness. The screwdriver also includes diametrically opposed, radially extending blades of constant thickness arranged perpendicular to the blades of radially varying thickness. Tapered blades having a thickness which increases with distance from the screwdriver axis are disclosed in one embodiment in which the blades also have a convex end surface, for use with a screw having a convex head.

Abstract: An eagle wing tips tamper-proof fastener and driver tool with complementary driver head contact for operating the same. A conventional threaded shank is perpendicularly connected to a substantially flat head. The head comprises a plurality of recessed channels numbering three and the channels radially curve outwards from a common center point. In one embodiment, the substantially vertical right and left walls of each channel allow application of torque with the driver tool in both directions. In an alternate embodiment, the substantially vertical right wall and the surface of the substantially inclined left wall allow application of torque with the driver tool to the right only.

Abstract: A recessed screw has a recess formed in the head of screw, with the recess being defined as a superimposition of two equilaterally-triangular recesses each having vertices shaped arcuate and arranged coaxially with a phase shift of 60.degree. around the screw axis. The recess thus has alternating six grooves and six driven vanes having side walls extending parallel with the axis, and an inner ridge of vane is a conically curved sticking wall inwardly slanted towards a bottom of the recess. A cross-sectional area of groove is larger than that of each vane. A driver bit has six driving vanes in conformity with the grooves and six valleys each interposed between the adjacent driving vanes and corresponding to the driven vanes in the recess, such that a biting action appears between the recess and bit, the driving vanes can be strengthened, and any conventional bit for Torx screws can be used with the recessed screw.

Abstract: A threaded tubular fastener having an elongated central through-bore having engaging means for engaging said through-bore with a rotary device having a rotary driver, a generally cylindrical body having an external surface with a main external thread formed thereon with a plurality of slots, said thread being larger than the diameter of a pre-drilled hole in a first work piece and a second mating work piece wherein the said threaded tubular fastener is employed to fasten the first work piece to the second work piece.

Abstract: The present invention describes a new and novel screwdriver head designed for use specifically with combo screws or uni-screws. The screwdriver head has a shank and a head having opposite mounted single straight ribs or blades of the type used on a standard flat-bladed screwdriver, and, perpendicular thereto, a pair of ribs of the Phillips headed screwdriver type. In between the pairs of ribs are recessed areas for connecting with the walls of the combo-screws.

Abstract: A driver bit adapted to engage in a recess of a recessed screw which recess is defined as a coaxial superimposition of two equilaterally triangular and cylindrical recesses each having arcuate vertices and arranged with a phase shift of 60.degree. about a center axis of the recessed screw to provide six engagable grooves and six driven vanes. The driver bit includes six driving vanes and six valleys, with each driving vane being shaped in conformity with each groove in the recess of the recessed screw, and with each valley being interposed between adjacent driving vanes and shaped in conformity with each driven vane in the recess of the recessed screw.

Abstract: A driver assembly for driving fasteners into a workpiece comprises a multilobular fastener engaging portion for engagement in a complementary multilobular socket or recess on a fastener. Each lobe is bounded on opposite sides by a flute, and each lobe includes a driving side wall and a trailing tapered side wall. The driving side walls are adapted to contact the complementary lobular portions of the fastener for applying torque to the fastener, while the trailing tapered side wall is aligned to contact the complementary lobular portion in wedged engagement at a point when the fastener is applied to the fastener portion. A fastener socket is also provided having a driven side wall and a trailing tapered side wall, which is constructed substantially similarly to the tapered side wall of the drive bit and which provides similar attributes.

Abstract: For its drive a screw is given a recess, which has an outer contour diverging from the circular shape. In the radial inner area and/or radial outer area of the recess the side walls are formed by individual surfaces located on a conical surface.

Abstract: A plug manipulator tool for closing off the suction outlet of a skimmer of a swimming pool comprises a threaded hollow plug body having a cap resiliently held on the top thereof. The cap is provided with an elongated handle on the top surface thereof which enables the threaded plug to be remotely engaged within the threaded opening of the suction outlet of the skimmer by an operator twisting the outer end of the elongated handle. In order for the operator to remotely remove the plug while the circulating pump for the swimming pool is running, the operator tilts the upper end of the elongated handle to thereby tilt the cap so that water in the skimmer can flow into the hollow plug body and down through the suction outlet thereby breaking the suction holding the cap on the top of the hollow plug body.

Abstract: A driver is designed for coaxial and non-coaxial driving of a fastener with a lobed drive recess. The driver has a part spherical drive head connected by a neck to the drive end of a shank coaxially therewith, the outer surface of the head defining circumferentially alternating lobes and valleys extending longitudinally in planes containing the driver axis. The head is shaped such that its longitudinal cross section in one of the planes through a valley defines a central part-spherical portion and frustoconical end portions substantially tangent to the central portion respectively at its opposite ends. The head is further shaped so that, in its transverse cross section, each of the lobes has a leading flank and a trailing flank shaped and dimensioned that the flanks do not define undercuts which would make molding of the driver difficult.

Abstract: A polygon headed wrench comprising a shank, a neck and a head, the head being provided with: flat surfaces extending in parallel to a central axis of the wrench; vertically aligned first tapered surfaces and vertically aligned second tapered surfaces, the first tapered surfaces and the second tapered surfaces gradually tapering the wrench head from its middle to extend in continuation to each flat surface toward the wrench central axis vertically and symmetrically with respect to an axis extending perpendicularly to the wrench central axis; and edge surfaces which extend from and in the same number as of the vertically lower second tapered surfaces of vertically aligned second tapered surfaces and converge into the wrench central axis, and a neck comprising third tapered surfaces which extend from and in the same number as the upper second tapered surfaces toward the central axis of the wrench and toward the shank.

Abstract: A threaded fastening member includes an actuating end having a head. The head has a diameter projecting beyond a diameter of the thread of the fastening member and is coaxial with a thread axis. A centrally located recess is provided within the head for the application of interior forces. The recess includes radial outwardly projecting slots, each having two flanks lying in respective planes. Each flank plane is essentially tangential to an imaginary cone that is co-axial with the thread axis. The recess further includes a pair of segmented circumferential faces separating each slot from an adjacent slot, and a transitional linear inner edge formed between each pair of segmented circumferential faces and each flank of a respective slot.

Abstract: A driver assembly for driving fasteners into a workpiece comprises a multilobular fastener engaging portion for engagement in a complementary multilobular socket or recess on a fastener. Each lobe is bounded on opposite sides by a flute, and each lobe includes a driving side wall and a trailing tapered side wall. The driving side walls are adapted to contact the complementary lobular portions of the fastener for applying torque to the fastener, while the trailing tapered side wall is aligned to contact the complementary lobular portion in wedged engagement at a point when the fastener is applied to the fastener portion. A fastener socket is also provided having a driven side wall and a trailing tapered side wall, which is constructed substantially similarly to the tapered side wall of the drive bit and which provides similar attributes.

Abstract: The subject apparatus is an improved screw driver adapted to have an expanding head to adapt to different screw head types and sizes, such screw driver device apparatus comprising a hollow handle member affixed concentrically to a hollow shaft, with the hollow shaft member holding a plurality of movable rod members that are adapted to move axially and longitudinally, within a limited distance in such hollow shaft member towards the head of the screw driver to move the ends thereof into position on the head of the screw.

Abstract: A screwing tool, particularly a screwdriver (1) or screwdriver bit, for polygonal socket screws (8), having flank sections (12) which are convex in circumferential direction; in order to optimize the transmission of force it is proposed that the flank sections (12, 12') be interrupted in the central region of each flank (11) by a non-convexly extending intermediate section (13/13').

Abstract: There is disclosed a torque transmitting or coupling arrangement for a fastener drive system or the like, wherein the respective externally configured and internally configured components are provided with a series of mating, elliptically curved flutes and lobes. In both the externally and internally configured components, the flutes and lobes are defined by a first series of elliptically curved surfaces which alternate with a second series of elliptically curved surfaces, with the respective surfaces merging smoothly and generally tangentially to define the alternating flutes and lobes on each said component. One of the components, either the externally configured or the internally configured component will preferably have the flutes and lobes thereon generated from ellipses of substantially equal dimension. The other component, of necessity, will have the flutes and lobes generated from ellipses of differing dimensions.

Abstract: A slot screwdriver with convex wide-side surfaces of the blade (3, 19) on its working end (8, 20) and, in order to optimize the use thereof, it proposes that the convexity be formed of two convex arcs (10, 21) present on each wide-side surface and lying symmetrically on both sides of the transverse center plane (A--A) of the blade (3, 19).

Abstract: A drive element for use with TORX.sup..RTM. compatible fasteners with an elliptical cross-section attached to an elongated shaft along the central longitudinal axis of the shaft. The minor axis of the ellipse extends along the central longitudinal axis of the elongated shaft. The elliptical cross-sections of the drive element are located on planes which pass through the minor axis. A major axis plane perpendicular to the minor axis is located at the center of the drive element. The drive element has elevations forming drive lobes and depressions which traverse a longitudinal elliptical path on the surface of the drive element. The lobes and depressions are substantially complimentary to the inner surface of a fastener cavity at the major axis plane. Starting at the major axis plane, the lobes become narrower as they approach the minor axis. The centers of curvature for the tops of the lobes are a series of points which define a first reference circle on the major axis plane with the minor axis as the center.

Abstract: A fastener drive tool for applying a rotational torque to a threaded fastener for driving the fastener into or out of a workpiece. The drive tool has an elongated shaft portion with a free end which is engageable with a recess formed in the fastener. Alternating merging concave and convex partially-cylindrical surfaces are formed on the outside of the shank towards the free end of the drive tool. The axes of curvature of the concave and convex partially-cylindrical surfaces are generally parallel to one another. The drive tool has at least one interlobular fastener retention piece attached between two convex partially-cylindrical surfaces which engage a corresponding convex partially-cylindrical surface formed in the fastener recess. The interlobular fastener retention piece releasably retains the fastener on the drive tool when the drive tool is engaged with the recess formed in the fastener and prevents wobbling of the fastener when it is driven by the drive tool.

Abstract: A screw fastener and a tool for driving the screw fastener is disclosed. The screw fastener has a polygonal driving socket in its head, the driving socket having a substantially square first section and a second section including a rectangular slot radiating outwardly from the center of each side wall of the first section. The depth of the first and second sections are the same. Further, the screw fastener may be provided with internal ducts for conveying lubricant into a workpiece hole in which the fastener is being turned. A driving tool having a square shank for turning the screw fastener is also disclosed. One end of the tool's shank has a driving section comprising a rectangular fin extending longitudinally along and radiating outwardly from the center of each side wall of the shank. The shape of the driving section is complementary in shape to, and dimensioned to be snugly received in, the driving socket.

Abstract: There is disclosed a torque transmitting or coupling arrangement for a fastener drive system or the like, wherein the respective externally configured and internally configured components are provided with a series of mating, elliptically curved flutes and lobes. In both the externally and internally configured components, the flutes and lobes are defined by a first series of elliptically curved surfaces which alternate with a second series of elliptically curved surfaces, with the respective surfaces merging smoothly and generally tangentially to define the alternating flutes and lobes on each said component. One of the components, either the externally configured or the internally configured component will preferably have the flutes and lobes thereon generated from ellipses of substantially equal dimension. The other component, of necessity, will have the flutes and lobes generated from ellipses of differing dimensions.

Abstract: A device is provided for inserting and removing a collet into and from a collet chuck of a lathe. The collet includes a plurality of fingers which are separated by slots. The device comprises a handle portion and a plurality of blades attached to the handle portion. The plurality of blades are adapted to engage the slots within the collet such that when the handle portion is turned, the collet is threaded into or out of the collet chuck.

Abstract: A modified Phillips-type screwdriver bit is disclosed that is fully compatible with a standard Phillips-head fastener, and is designed to significantly increase the level of torque that can be applied to the fastener while at the same time substantially reducing the cam-out forces normally produced by a standard Phillips screwdriver bit. These results are accomplished by forming generated surfaces along the side walls of the bit wings so that when the bit is initially inserted into a standard Phillips-head fastener, lines of contact occur between the bit and recess adjacent and parallel to the roots of the bit wings. In this manner, the application of torque is confined to the sides of the bit wings even as applied torque levels increase.

Abstract: A rotatable driving tool for imparting torque to a driven member, such as a threaded fastener having an axial recess in the head thereof, comprises a circularly cylindrical body with a plurality of substantially circularly helical driving portions projecting laterally therefrom and equiangularly spaced about the cylindrical axis, each of the driving portions having a small helix angle, preferably between one and three degress. The driving portions mate with lobes of the fastener recess but are slightly inclined with respect thereto to provide a wedge fit to retain the fastener in engagement with the tool body.

Abstract: A rotatable coupling having a male member (2) and a female member (4) each rotatable about central axes .alpha. and .beta.. The male member has lobes (16) and the female member cavities (50) for mutual engagement. The male lobes terminate in wedge-shaped portions (18), the edges of which lie in a common plane. The female terminates in a flat bottom surface (40).

Abstract: A screwdriver and mating screw are shown with interlocking features for coupling with one another to facilitate driving the screw into a workpiece. The screwdriver includes a handle and a blade with an engagement flange on the outer extremity of the blade. The engagement flange engages a complementary recess provided in the head of the mating screw, the recess including a downwardly facing shoulder. A coupling sleeve mounted on the blade exerts an axially directed force on the screw once the engagement flange and complementary recess are engaged to thereby interlock the screwdriver and mating screw.

Abstract: An anti-theft system is provided for articles such as modular equipment installed into vehicles with Allen type machine bolts. The system employs a monolithic insert member which is bonded within the hexagonally contoured depression in the head of the machine bolt, and has a protruding portion having a distinctively shaped keying configuration. A turning tool is provided having a handle and a shaft. The distal extremity of the shaft has a recess having a configuration adapted to receive the keying configuration of the insert member.

Abstract: A cassette tape winding device 10 comprising: a scored, tapered conical portion (12); a generally cylindrical intermediate shaft portion (13), and a toothed driving portion (14) having a plurality of elongated driving teeth (16) spaced from one another and arranged in a circular pattern on the bottom surface of the intermediate shaft portion.

Abstract: A locknut having a body portion with an outer surface and first and second ends, a thread extending inwardly into the body portion from the first end, a depression in the second end, an inwardly tapered lobed curvilinear surface defining the periphery of the depression for receiving a mating key, and an external thread extending from the second end onto the outer surface for receiving the internally threaded surface of a sleeve mounted on a key for attaching the key to the locknut. The locknut as described above including a rotatable sleeve mounted thereon with a shroud located radially outwardly of the external thread. A locknut as described above wherein the outer surface extending from the first end is frustoconical and terminates at an annular shoulder which is located radially outwardly of the external thread.

Abstract: Correspondingly keyed combination of a round-headed bolt fastener and a generally cylindrical socket, preferably for use in securing an automobile wheel cover against theft. The fastener has a plurality of axial slots, or lock impressions, about the periphery of the circular head which may be spaced in accordance with a preselected code. The wrench socket is provided with a corresponding number of key elements projecting inwardly from the cylindrical wall of the socket, the position of the key elements being in accordance with a preselected code. When the key code of the wrench matches the lock code of the fastener, the wrench socket may be slipped over the fastener head with the key elements engaging the lock impressions so that the wrench may tighten or untighten the fastener. The fastener has an axial recess extending from the outer face of the head with an inner beveled surface about the recess opening.

Abstract: A non-slip screw of the type having a threaded shank and a slotted head, including a locking surface defined in the screw head by a central transverse slot which extends across the top of the head for engagement with a screwdriver blade tip. The locking surface includes a pair of radially outwardly extending inclined walls extending downwardly from each end of the transverse slot. An especial screwdriver having its exterior blade tip configured complementally with the pairs of radially outwardly extending inclined walls is engageable with the locking surface, so as to rotate the screw head in either direction. The screw head is characterized by its positive grip with the screwdriver blade tip, notwithstanding actual screwdriving or unscrewing and removal of the screw.

Abstract: A screwdriver is provided that can be used for installing and removing either single slot screws or screws having two slots that cross at their centers, i.e., "PHILLIPS" type screws. The screwdriver is provided with a shaft which includes a tip segment having a configuration suited for engagement in the slots of such a cross-slotted screw. An elongated slot is in the tip segment along the length of the shaft. A blade, suited for engagement in the slot of a single slot screw, is slidably mounted in the tip segment slot. When the blade is in a first position extended beyond the end of the shaft tip segment, it can be engaged in the slot of such a single slot screw. When the blade is in a second position retracted or housed within the elongated tip segment slot, the tip segment can be engaged in the slots of such a cross-slotted screw.

Abstract: A combination of a cruciform recess in a fastener and cruciform driver has driver wings 13 which are narrower than corresponding recess radial grooves 21 and has downwardly tapered grooves and wings such that driving engagement between driver and fastener takes place at the outer upper edges of the recess. There is a relative downward taper between the wing width and groove width and these widths are so selected that the lower ends of the wings are confined by and preferably wedge in the recesses.

Abstract: An insert type drive tool (20) is configured to be insertable within both a square-shaped cavity (32) and a hexagonal shaped cavity (40) of the same size. In cross section shank (24) of tool (20) includes a pair of major sides (26) disposed in spaced parallel relationship to each other, and a pair of minor sides (28) also disposed in spaced parallel relationship to each other. The minor sides (28) are disposed substantially perpendicularly to the major sides (26) and are spaced apart from each other substantially the same distance separating the major sides (26). Two pairs of intermediate sides (30) extend diagonally from each end of major sides (26) at an angle of approximately 120.degree. to intersect an adjacent end of a corresponding minor side (28).

Abstract: A modified Phillips-type cruciform recess in a screw or the like, which provides a cling-fit with a driver by causing deflection of the flutes of the driver against the walls of the slot in the recess, comprises a central socket portion and radially extending slots adapted to receive the flutes of a suitable driving tool. Each slot is defined in part by a bottom surface of substantially uniform width which slopes radially inwardly and downwardly along the axis of the screw. The bottom surface joins two opposing surfaces which form the walls of the slot. The pairs of opposite slots in the cruciform pattern are not symmetrically located relative to a plane including the longitudinal axis of the screw, but are offset laterally in opposite directions with respect to such a plane. On insertion of a standard driver into the recess, the flutes of the driver are caused to flex into frictional engagement with the walls of the slots, thereby achieving the desired cling-fit.

Abstract: A driving tool and fastener, in the driving end of which is provided a nick or slot for insertion of the driving tool for driving the fastener, are provided which, because of their particular, respective cross-sectional configurations, can be interlocked temporarily together. As this interlocking engagement prevents the driving tool from accidentally slipping from the nick in the driving end of the fastener, rotational movement of the fastener is greatly facilitated. The shank of the driving tool is provided at its operative end with a bit that, because of its cross-sectional configuration compared to that of the nick, wedges with the nick. Thus, not only is slipping between the driving tool and fastener prevented when rotating the fastener, but accidental separation of the driving tool from the fastener is prevented, making the task considerably easier when using the fastener in overhead work or in a hard to reach location.

Abstract: A tool for engaging nipples to be applied to or removed from threaded pipe has a plurality of circumferentially spaced longitudinally extending gripping edges formed on elongated members which are arranged in a tapered configuration relative to the longitudinal axis of the tool.

Abstract: There is disclosed an improved fastener and driver assembly which assures sufficient depth of engagement between the drive socket of the fastener and the working portion of the driver bit to provide efficient torque transfer from the driver to the fastener. The assembly includes a fastener having a recessed drive socket which is multi-lobular in cross-section, having an inner surface formed by alternating and smoothly joined flutes and lobes. The assembly also includes a driver for imparting rotational torque to the fastener which includes a head portion having a tip end and a center axis. The head portion of the driver is correspondingly multi-lobular in cross-section. The flutes are formed generally parallel to the center axis of the driver while the lobes of the head portion are tapered axially, converging toward the tip end of the head portion.

Abstract: A recess for fasteners such as screws, bolts and the like having, in axial alignment with the shank, a central recess of a conic-frustum shape which serves as a natural center for a driver tool or for a drill bit if it becomes necessary to drill out the fastener. The wrenching elements consist of a plurality of truncated conic segments having their common center line axis coincident with the central recess. The wrenching walls for loosening lying in a plane containing the center line axis of the fastener while the walls for tightening being sloped toward the tightening direction to provide for torque limiting.