Abstract: A non-slip screw of the type having a threaded shank and an embedded slotted head, including a locking surface defined in the screw head by a central transverse slot which extends into the top of the head for engagement with the driver blade tip. The locking surface includes a pair of off-set blades outwardly extending walls extending downwardly from each end of the transverse slot. A river having its exterior blade tip configured complementary with the pairs of off-set blades outwardly extending inclined walls is engageable with the locking surface, so as to rotate the screw head in either direction.

Abstract: A compound screwdriver head, which comprises a first working portion and a second working portion of the same size, the first, second working portion of the bigger size is used for screwing and unscrewing a bolt of bigger, smaller size respectively, so that different sizes of bolts can be locked and unloaded by one screwdriver. Thereby this invention is not only can save the structure of the bolt, but also can prolong the life of the bolt.

Abstract: A screw head and screwdriver for use in combination are provided to reduce the occurrence of stripping a screw head during tightening or removing the screw. The head slot employs slot walls that indent in some portion of the wall, the indent portion forming a ledge under which the screwdriver tip may be retentively captured thereby preventing the tip from lifting from the screw slot and stripping the screw head. The screw slot and driver also generally employ a tapered form, such that the slot widens from a central portion out to the outer circumferential edges. The narrow portion of the slot matching in form a narrow portion of the driver tip such that the driver tip tends not to slide off the screw head during use. Utilizing these inventive design concepts prevents the screwdriver tip from slipping off the head and resulting in the need to apply less downward pressure.

Abstract: The invention provides a screw head having a hexalobular slot (2) in the upper surface of the screw head, an upper peripheral wall (9) of hexalobular planform extending down into the screw head, the upper peripheral wall (9) being parallel or near parallel to the axis of the screw, a sloping transition surface (15) extending downwardly and inwardly with respect to the lower edge of the upper peripheral wall (9), and a tapered recess (11) extending downwardly from the lower edge of the sloping transition surface (15), in which the dimensions of the screw head are such that when the screw head is engaged by a tool (6) having upper (16) and lower engagement (17) sections, the lower engagement section (17) is tapered, and there is a ‘stick fit’ between the surface of the tapered recess (11) and the external surface of the lower tapered engagement section (17), and there is no engagement with the sloping transition surface (15).

Abstract: A driver has a tip that enables it to engage each one of a conventional hexagonal-head fastener and a conventional lobed-head fastener. The tip includes alternating flutes and crests. The crests are substantially flat to engage straight walls of a hexagonal-head. The flutes engage the lobed head of the fastener. A socket-type driver engages each type of conventional fastener. A fastener and a pair of socket-type fasteners have alternating flutes, which can be engaged by a conventional lobed-head driver, and crests or sidewall surfaces, which can be engaged by a conventional hexagonal-head driver.

Abstract: A threaded screw fastener is provided with a head portion that has integrally incorporated therein dual drive structure whereby the single threaded screw fastener can be rotatably driven by alternative rotary drive socket implements or tools, such as, for example, hexagonally configured or Phillips head configured drive tools or implements, or a combination drive tool. A drive socket implement or tool also has integrally incorporated therein both hexagonally configured drive structure, Phillips head drive structure, and domed contour structure for not only structurally engaging both the hexagonally configured structure and the Phillips head structure integrally incorporated upon the head portion of the threaded screw fastener, but in addition, accommodates the low profile domed structure of the head portion of the threaded screw fastener.

Abstract: A fastener impact driver device includes a fastener engagement member having a plurality of projections disposed about a lower portion that engages a corresponding peripheral portion of a fastener. The device further includes a positioning member having an upper portion that ultimately receives a force thereupon, and a lower portion that engages a cooperating upper portion of the fastener engagement member whereby a force such a hammer strike is imparted upon the upper portion of the positioning member to drive the projections of the fastener engagement member into the head of the fastener without damage of the fastener engagement member, whereupon the positioning member is removed from the fastener engagement member and a hand tool is removably secured to the fastener engagement member to impart rotary motion to the member and the fastener thereby removing the fastener from or urging the fastener into a workpiece.

Abstract: The invention pertains to a screwdriver bit with a drive section (14) and a front section (1) that contains a profiled penetrating section (2) and is manufactured by compression molding and subsequently sintering a hard metal powder, where the front section is connected to the drive section. Thus, according to the invention, the length of the front section (1) is not greater than 2.5-times the length of the penetrating section (2) and/or the ratio of the length of the front section (1) to the diameter or the width across corners of the penetrating section (2) is not greater than 2.2 (FIG. 7).

Abstract: A combination fastener driver and fastener, the fastener driver including a generally hourglass-shaped tip which flares from the shank to the tip and the fastener includes a generally hourglass-shaped slot in the fastener head with under cut side walls. The flared walls of the driver tip engage the undercut side walls of the fastener slot to lock the tip in the slot when driving the fastener. A waist portion in the driver tip engages a waist portion in the fastener slot to prevent the tip from laterally slipping out of the slot during use.

Abstract: Related to a tamperproof screw to which a conventional general screwdriver cannot couple so that screw tightening is prevented reliably, to a screwdriver bit that can be simply and quickly coupled to the screw and can reliably prevent a come-out phenomenon during screw tightening, and to a header punch for manufacturing the tamperproof screw simply, easily and at low costs.

Abstract: A screw (10) has a threaded shank (12) and a head (14). The head has a recess (18) that comprises three lobes (18a,b,c). Each lobe is separated by a curved drive flange (20a,b,c,). A driver (100) has a drive tip (114) that fits the recess of the screw.

Abstract: A screw and a screwdriver of the present invention provide an easy insertion of screwdriver bits and the screwdriver conveys a large torque when fastening so that the screwdriver does not rise up from the screw and does not damage recesses to fasten and loosen the screw. The screw has a high strength structure for shear force. A plurality of recesses for the insertion of the bits of the screwdriver are disposed on a top face of a screw head of the screw. Engaging walls are disposed to engage with the bits between the recesses. The whole shape of the recesses has a tapered cross section. Vertical engaging faces are formed inside the recesses near an outer circumference in a fastening direction of the screw and extend to a thickness direction of the screw head. The vertical engaging faces are parallel to bisectors of the width of the engaging walls through a central axis. The screwdriver has the bits having the same shape as the recesses of the screw head with respect to the central axis.

Abstract: A screw (10) has a threaded shank (12) and a head (14). The head has a recess (18) that comprises three lobes (18a, b, c). Each lobe is separated by a curved drive flange (20a, b, c). A driver (100) has a drive tip (114) that fits the recess of the screw.

Abstract: A screw positioning device for a screwdriver comprises a connecting rod assembly, a screw positioning sleeve and a magnetic member. The screw positioning sleeve is axially defined with a slide hole for insertion of an end of the connecting rod assembly, the magnetic member is installed on inner peripheral surface of a front end of the screw positioning sleeve, the screw positioning sleeve is axially positioned at the end of the connecting rod assembly, and the positioning sleeve can move back and forth a predetermined distance with respective to the connecting rod assembly.

Abstract: A screw and a screwdriver of the present invention provide an easy insertion of screwdriver bits and the screwdriver conveys a large torque when fastening so that the screwdriver does not rise up from the screw and does not damage recesses to fasten and loosen the screw. The screw has a high strength structure for shear force. A plurality of recesses for the insertion of the bits of the screwdriver are disposed on a top face of a screw head of the screw. Engaging walls are disposed to engage with the bits between the recesses. The whole shape of the recesses has a tapered cross section. Vertical engaging faces are formed inside the recesses near an outer circumference in a fastening direction of the screw and extend to a thickness direction of the screw head. The vertical engaging faces are parallel to bisectors of the width of the engaging walls through a central axis. The screwdriver has the bits having the same shape as the recesses of the screw head with respect to the central axis.

Abstract: A screw having a screw-threaded shank and a circular head, the head being provided with three radially extending screwdriver tip receiving portions defined between three first, off central integrally formed projections designed to become shaved-off the screw head by a pre-set force applied during tightening of the screw, and three second, integrally formed projections designed to withstand a shear force greater than the pre-set force applied during slackening of the screw.

Abstract: The present invention provides a screw, comprising a screw head having a drive recess and a screw shank having threads and being integrally formed with the screw head, wherein the drive recess includes a plurality of engaging grooves equiangularly radiating from an axis of the screw in plan view, a bottom face of each engaging groove having a steep slope, which is near to the screw shank, and a gentle slope, which is far from the screw shank, for enlarging the engaging area of the engaging grooves.

Abstract: The present invention provides a fastener that can be used with a variety of bits as well as a fastener with several security features that can be used only with a very specialized bit and, also, a fastener/bit combination that can be used in conjunction with high-torque power tools. Specifically, this invention allows the use of a straight blade, a three-blade or a five-blade driver with the same fastener head.

Abstract: A key for operating a security fastener having a lock pattern includes a retractable key pattern. The key pattern has an operational extension position in which the key pattern is enabled for substantial engagement with a security fastener having a matching lock pattern, thereby allowing operation of the matching security fastener. The key pattern is also capable of retreating a non-operational retraction position in which the key pattern is not capable of substantial engagement with a security fastener having a non-matching lock pattern, thereby preventing operation of the non-matching security fastener.

Abstract: A fastener impact driver device 10 includes a fastener engagement member 12 having a plurality of projections 14 disposed about a lower portion 16 that engages a corresponding peripheral portion 18 of a fastener 20. The device 10 further includes a positioning member 22 having an upper portion 24 that ultimately receives a force thereupon, and a lower portion 26 that engages a cooperating upper portion 28 of the fastener engagement member 12 whereby a force such a hammer strike is imparted upon the upper portion 24 of the positioning member 22 to drive the projections 14 of the fastener engagement member 12 into the head 44 of the fastener 20 without damage of the fastener engagement member 12, whereupon the positioning member 22 is removed from the fastener engagement member 12 and a hand tool is removably secured to the fastener engagement member 12 to impart rotary motion to the member 12 and the fastener 20 thereby removing the fastener 20 from or urging the fastener 20 into a workpiece.

Abstract: System comprising a crew and a tool (6) therefore, in which the screw head (1) with a slot (2), the slot (2) having a first recess (3) with an approximately straight-walled cross section, and the tool being provided with an engagement section (16) that is complementary to the first recess (3). The slot has a second recess (11) at the bottom of the first recess (3), with a smaller diameter than that of the recess (3), and the tool (6) is provided with a central point (17) that complements the second recess (11). The second recess (11) has a circular cross section and the central point (17) has a circular cross section.

Abstract: A combination of a screw and a screw driver bit and a header punch for its manufacture capable of effectively preventing a come-out phenomenon of the screw driver bit by improving the structure of a groove part in a cross groove part in a cross groove of a screw to prevent a conventional damage.

Abstract: The invention provides a bit (10) for use with a rotatable tool, said bit including: a shaft (12) having a rearward end adapted to be held by a chuck of the rotatable tool, and a forward end (18) having cutting tips formed thereon; a reaming head (14) including a body having a bore (16) adapted to receive the shaft therethrough in a sliding fit, the body having a plurality of cutting blades (26) formed on at least one peripheral surface thereof; the bore and/or the shaft having formations thereon such that when the rearing head has the shaft operatively located in the bore the reaming head is rotationally locked into the shaft; the reaming head and the shaft being separable from each other to allow either component to be replaced independently of the other.

Abstract: A device for use in a torque transmitting system including a driver having a specially configured driver end and a fastener having a specially configured recess for receiving the end of the driver, wherein the respective externally configured and internally configured components include a body having an axis in which the body has an outer polygonal cross section defined by a perimeter wall, an inner polygonal central portion positioned within the perimeter wall and having an area less than the area of the outer polygonal cross section; a drive wall which forms a portion of the perimeter wall and 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 which may be less than 90° and a distal end terminating on the perimeter wall.

Abstract: A bicycle crank arm apparatus includes an axle having a first end portion and a second end portion, wherein the first end portion has an outer peripheral surface and a threaded inner peripheral surface; an axle bolt having a threaded outer peripheral surface screwed into the threaded inner peripheral surface of the first end portion of the axle; a crank arm having an axle mounting boss defining an opening for receiving the first end portion of the axle therein, wherein the axle mounting boss includes a first fastener for tightening the crank arm mounting boss around the first end portion of the axle; and wherein the crank arm boss is positioned axially inwardly of the axle bolt.

Abstract: The invention pertains to a screwdriver bit with a drive section (14) and a front section (1) that contains a profiled penetrating section (2) and is manufactured by compression molding and subsequently sintering a hard metal powder, where the front section is connected to the drive section. Thus, according to the invention, the length of the front section (1) is not greater than 2.5-times the length of the penetrating section (2) and/or the ratio of the length of the front section (1) to the diameter or the width across corners of the penetrating section (2) is not greater than 2.2 (FIG. 7).

Abstract: A screwing tool having a torque-introduction part (2) with a cavity (4) in which a profile body (3) is inserted in a rotationally fixed manner, the profile body forming, by its section which projects out of the cavity (4), an operating end (1) for torque-transmitting insertion into a screwing-tool entry opening of a screw head, wherein the torque-introduction part (2) forms a polygonal section for inserting the screwing tool into a screwdriver mount or a bit holder, and the operating tip (1) is rotable, counter to a restoring force, in relation to the cavity-opening edge (4′) as a result of the profile body (3) being secured in the cavity (4) such that it is capable of torsion, having a torsion section (16) formed as a torsion bar. The profile body (3), which is produced from a hardened steel, forms the torsion section (16), which is fitted, by a securing section (18), in the base (4′″) of the cavity, the base being coordinated to polygonal section (17).

Abstract: The present invention provides a fastener, such as a screw or nut and tool designed in particular for use with an orthopedic implant system wherein the fastener has a multi-lobed torque driving recess. The recess has a central area bounded by equally spaced hemicircular grooves separated by internally projecting land having two sharp edges. The tool has a corresponding male shape, which in conjugation with the recess, is designed to achieve a controlled torque load with a minimized possibility of stripping the recess or of shearing the torque-driving tip from the tool.

Abstract: An anti-skip fastener tightening and/or extraction device 10 includes a tool bit end 12 having a plurality of flutes or crossing members 13-16, each crossing member having at least one recess 18 and 26 positioned in a side wall 20,21,28 and 29. The recesses 18 and 26 form edges 36 and 42 that engage corresponding portions of a fastener 17 to maintain engagement between the tool bit end 12 and the fastener 17 when forcibly rotating the fastener 17 to drive the fastener 17 into a workpiece or forcibly rotating the fastener 17 to extract the fastener 17 from a workpiece.

Abstract: A fastener is described having a head formed with a recess which accommodates a square head driver, symmetrical drivers, such as PHILLIPS™ style drivers, asymmetrical style cross head drivers, such as POZIDRIV® style drivers, and combination square and cross drivers without compromising performance of the drivers.

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: An anti-skip fastener tightening and/or extraction device 10 includes a tool bit end 12 having a plurality of flutes or crossing members 13-16, each crossing member having at least one recess 18 and 26 positioned in a side wall 20,21,28 and 29. The recesses 18 and 26 form edges 36 and 42 that engage corresponding portions of a fastener 17 to maintain engagement between the tool bit end 12 and the fastener 17 when forcibly rotating the fastener 17 to drive the fastener 17 into a workpiece or forcibly rotating the fastener 17 to extract the fastener 17 from a workpiece.

Abstract: A driver bit and a header punch for manufacture of screws comprising a screw comprising substantially vertical end wall portions of predetermined depth formed on an end edge portion of a bit fitting groove on a screw head, non-planar bottom portions raised from lower edge portions of the vertical end wall portions toward a center of the screw head, inclined groove portions extending from raised portions of the non-planar bottom portions toward a center of a screw neck, a substantially conical-shaped bottom surface formed on a bottom of the groove, the bit fitting groove being adapted to a driver bit, which has a blade adapted to be fitted into the bit fitting groove and has a lower edge portion of the blade adapted to abut against the non-planar bottom portions.

Abstract: An accommodating head for a tool which has an actuating tip and is intended for turning fastening elements, the tool having a drive element and an output element, it being possible for a torque to be introduced into the drive element and the tool being arranged in a rotationally fixed and pivotably mounted manner in the output element. In torque transmission from the actuating tip to the fastening element, the distance between the pivot axis of the actuating tip of the tool and the fastening element is small enough for the line of action of a force running along a longitudinal center axis of the output element to intersect the fastening element even in each pivoting end position of the tool and the actuating tip thereof.

Abstract: A device for use in a torque transmitting system including a driver having a specially configured driver end and a fastener having a specially configured recess for receiving the end of the driver, wherein the respective externally configured and internally configured components include a body having an axis in which the body has an outer polygonal cross section defined by a perimeter wall, an inner polygonal central portion positioned within the perimeter wall and having an area less than the area of the outer polygonal cross section; a drive wall which forms a portion of the perimeter wall and 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 which may be less than 90° and a distal end terminating on the perimeter wall.

Abstract: A screw has a head portion and a threaded portion. The head portion has an undercut slot extending across it. The slot has a flat floor and sloping sides and the width of the floor of the slot is greater than the width at the top opening of the slot. A matching bit has a shank portion and a flat portion. The flat portion of the bit is not as wide as the top opening of the slot. The flat portion has a foot extending from each end.

Abstract: The invention relates to a screwdriver or screwdriver attachment (S) comprising one input and one output end (1 and 2) and a shank (4) located in between the two. The output end has at least three, preferably four, ribs (7) which radiate outwards from a central section (8) located around the axis of rotation (x—x). The ribs (7) on each end side have a face, which is placed at an angle to the axis of rotation, and flanks on the front and back side (13, 14) which run substantially parallel to each other in the area next to the frontal face (11). In this area the flank (13) on the front side is located on a diametrical surface (diameter D—D) in relation to the axis of rotation (x—x), whereby the flanks (13, 14) of adjoining ribs (7) form a groove (9) which runs lengthways and whose root (16) ends in the outer surface of a section of the shank.

Abstract: New system for holding and fastening screws comprising a screw head provided with a mortise hole (1) having a tapered configuration along the screw longitudinal axis, said mortise hole (1) having a number of lugs (2) and the corresponding circular sections (3); and comprising a suitable screwdriver o fastening tool head tip (4) having a definite shape and wings (5), both according to the corresponding number of lugs (2) in order to match said screw head mortise hole (1); and comprising the required punching mortise die tool for the definite conformation of said screw head mortise hole (1) and said screwdriver or fastening tool head tip (4).

Abstract: The invention pertains to a screwdriver bit with a drive section (14) and a front section (1) that contains a profiled penetrating section (2) and is manufactured by compression molding and subsequently sintering a hard metal powder, where the front section is connected to the drive section. Thus, according to the invention, the length of the front section (1) is not greater than 2.5-times the length of the penetrating section (2) and/or the ratio of the length of the front section (1) to the diameter or the width across corners of the penetrating section (2) is not greater than 2.2 (FIG. 7).

Abstract: A cross-point shaped screwdriver has a cylindrical metal shaft with an axis coaxial with an insertion direction for driving a screw having a socket. A bit section, formed on the end of the shaft, has four blades. A circumferential groove is formed in the exterior of each of the blades. The grooves are in a single plane extending across a width of each plane. When the screwdriver engages the screw socket, the grooves substantially align with a top portion of the socket. The grooves provide a clearance between the bit section and upper end of the socket top, thereby reducing wear on the screw socket and permit the driver to engage and drive the screw at a depth that the standard driver can not engage and drive upon. Often the screw is rounded out by a standard driver.

Abstract: A screw with a polygonal hole (30) formed with a polygonal hole (32) disposed in the center of a screw head (30a) and comprising a vertical wall (33) with a preset depth, and with a cone base oriented from the lower edge of the vertical wall toward the center of a screw neck, wherein a vertical step forming an inscribed circle of the polygon is provided at the lower edge (33a) of the vertical wall (33) of the polygonal hole (32) formed in the screw head (30a), the cone base (35) oriented from the lower edge (34a) of the vertical step (34) toward the center of the screw neck is formed, and a driver bit (40) or wrench (41) to be fitted to this screw is provided at the tip of a peak edge (42) with a cylindrical projection (44) forming the inscribed circle of the polygon.

Abstract: A screwdriver bit (50) fitted to a screw wherein generally vertical end wall parts of a specified depth are formed in the bit fitting grooves of a screw head part at the end edge parts, a generally flat bottom part is formed directing from the lower edge part of the vertical end wall parts to the center part of a screw neck part, and a conical bottom surface is so formed at its center part, comprising flat blade parts (52) forming, at the top end parts, generally vertical end edge parts fitted into the bit fitting grooves of the screw head part along the vertical end wall parts, the top end surfaces of the flat blade parts being formed in a conical protruded part (54) having an inclination angle &thgr; of approx.

Abstract: A spiral drive system for threaded fasteners includes driver-engageable surfaces on the head end of the fastener in which at least some of the driver-engageable surfaces are defined by a spiral segment configured to maximize torque transmission while spreading the driving load over a broad driver-fastener interface to reduce the risk of development of high stress regions. Drivers and related tooling also are disclosed.

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 driver bit and a header punch for manufacture of screws comprising a screw comprising substantially vertical end wall portions of predetermined depth formed on an end edge portion of a bit fitting groove on a screw head, non-planar bottom portions raised from lower edge portions of the vertical end wall portions toward a center of the screw head, inclined groove portions extending from raised portions of the non-planar bottom portions toward a center of a screw neck, a substantially conical-shaped bottom surface formed on a bottom of the groove, the bit fitting groove being adapted to a driver bit, which has a blade adapted to be fitted into the bit fitting groove and has a lower edge portion of the blade adapted to abut against the non-planar bottom portions.

Abstract: A screw device, an assembly for theft-proofing vehicle wheels, and a motor vehicle with theft-proofed vehicle wheels is disclosed. The screw device has a screw with a head and a threaded portion intended to be screwed into a thread of a wheel hub, a sleeve and a lock member. The threaded portion is intended to be screw into the thread of the wheel hub via a recess arranged in a central portion of a vehicle wheel. The lock member is an endless, smoothly undulating or curved lock member. The dimensions of the sleeve are adapted to the dimensions of the recess so that regions of the central portion adjacent to the recess encompass substantially entirely and closely a circumference of the sleeve when the threaded portion has been screwed into the thread. The invention can be applied to all types of vehicle wheels, and is particularly advantageous for exclusive private cars with special rims.

Abstract: A driver bit and a header punch for manufacture of screws comprising a screw comprising substantially vertical end wall portions of predetermined depth formed on an end edge portion of a bit fitting groove on a screw head, non-planar bottom portions raised from lower edge portions of the vertical end wall portions toward a center of the screw head, inclined groove portions extending from raised portions of the non-planar bottom portions toward a center of a screw neck, a substantially conical-shaped bottom surface formed on a bottom of the groove, the bit fitting groove being adapted to a driver bit, which has a blade adapted to be fitted into the bit fitting groove and has a lower edge portion of the blade adapted to abut against the non-planar bottom portions.

Abstract: An accommodating head for a tool which has an actuating tip and is intended for turning fastening elements, the tool having a drive element and an output element, it being possible for a torque to be introduced into the drive element and the tool being arranged in a rotationally fixed and pivotably mounted manner in the output element. In torque transmission from the actuating tip to the fastening element, the distance between the pivot axis of the actuating tip of the tool and the fastening element is small enough for the line of action of a force running along a longitudinal center axis of the output element to intersect the fastening element even in each pivoting end position of the tool and the actuating tip thereof.

Abstract: At least one of two components (1, 3) of a coupling includes a profile with four splines (5) having more or less radial edges (11). Four straight-line segments (6) on the inside of the profile are joined with the splines. The four straight-line segments (6) are designed to circumscribe a standardized square drive (14). This profile can be used for driving sockets and accessories for screwing and unscrewing.

Abstract: A screw driver exclusively applied to drive a particular screw having compound drive recesses that can be driven by various conventional drivers, i.e., slot, cross, square-cross, square, and double-cross. The screw driver enables its drive bit to supply sufficiently large driving torques to the compound drive recesses of the screw and the screw driver lodges securely within the compound drive recesses of the screw as the drive bit of the driver turns.