COUPLING ARRANGEMENT AND TOOLS FOR SAME

• US 3,584,667 A
• Filed: 10/26/1969
• Issued: 06/15/1971
• Est. Priority Date: 09/19/1966
• Status: Expired due to Term

• Current Assignee: Bernard F. Reiland
• Original Assignee: Bernard F. Reiland
• Inventors: Reiland, Bernard F.
• Application Number:
  US04/872,180
• Time in Patent Office: 597 Days
• US Class Current: 81/460
• CPC Class Codes: B25B 13/065 characterised by the cross-section of the socket
• CPC Class Codes: B25B 23/0035 Connection means between socket or screwdriver bit and tool
• CPC Class Codes: F16B 21/18 with circlips or like resilient retaining devices, i.e. resilient in the plane of the ring or the like; Details spring-washers for locking nuts F16B39/24; adjusting rings F16B43/00
• CPC Class Codes: F16B 23/003 star-shaped or multi-lobular, e.g. Torx-type, twelve-point star
• CPC Class Codes: F16D 1/101 without axial retaining means rotating with the coupling
• CPC Class Codes: Y10S 411/919 Screw having driving contacts

Abstract

A torque-transmitting or coupling arrangement and tools for same consists of a body portion having a first series of similar arcuately curved surfaces with their centers of curvature located at the corners of a regular hexagon and which surfaces are disposed outwardly of such centers with respect to the axis of the body. A second series of surfaces curved oppositely to those of the first series and alternating therewith extend substantially to the sides of said hexagon midway between the corners thereof while the ends of the second series merge tangentially with adjacent ends of the first series. The radius of curvature of the second series is from two to three times that of the first series whereby the midpoint of said second series is closer to the axis of said body than the midpoint of said first series by an amount equal approximately to 50 percent more than the length of the radii of said first series. Moreover, each of the first series of surfaces has an angular extent of the order of 20 to 25* whereby the resultant shear area provided outwardly of the second series of surfaces is approximately double the shear area formed inwardly of the first series of surfaces. Also, contiguous surface portions of said two series of surfaces are formed defining a driving area of 10 to 20* whereby higher torques than heretofore possible can readily be transmitted from a driving unit to a driven unit of mating configuration without damaging either.

Claims

1. In an article of manufacture of the class described comprising a body including a portion having a first series of spaced apart, semicylindrical surfaces and a second series of semicylindrical surfaces alternating with the surfaces of said first series and merging tangentially therewith, the axes of curvature of said two series of surfaces extending substantially parallel with each other and with the central axis of said body;

the axes of curvature of said first series of surfaces being disposed between the respective corresponding surface and said central axis; and

the axes of curvature of said second series of surfaces being disposed on the opposite side of the respective corresponding surface with respect to said central axis;

the cross section of said surFaces of said portion being of symmetrical, generally hex-lobular configuration;

the axes of curvature of said first series of surfaces being coextensive with the apices of a regular hexagon;

the invention being characterized in that;

a. the radius of curvature of said first series being approximately 5 to 10 percent of the major diameter across said first series of surfaces;

b. the radius of curvature of said second series of surfaces being more than twice as great as that of said first series of surfaces whereby the angular extent of said second series of surfaces is materially greater than the angular extent of said first series of surfaces, the latter being of the order of 20* to 25*. c. the difference between the maximum radial dimension of said first series of surfaces and the minimum radial dimension of said second series of surfaces being approximately 50 percent greater than the radius of said first series of surfaces; and

d. contiguous surface portions of said first and second series of surfaces defining a driving surface with a drive angle of from 10* to 20*, the drive angle being defined as the angle between a line tangent to the point of contiguity of said surface portions and the radius of said body bisecting the semicylindrical surface of said first series of surfaces immediately adjacent said driving surface.

2. An article of manufacture according to claim 1 in which the difference between the maximum radial dimension of said first series of surfaces and the minimum radial dimension of said second series of surfaces is between 25 and 30 percent of said maximum radial dimension.

3. An article of manufacture according to claim 1 in which said first series of surfaces define convex ridges and said second series of surfaces define concave flutes on the outside perimeter of a driven unit.

4. An article of manufacture according to claim 1 in which said first series of surfaces define concave flutes and said second series of surfaces define inwardly extending convex ribs forming the internal sidewalls of a recess in a driven member.

5. An article of manufacture according to claim 1 in which said first and second series of surfaces define the internal sidewall surfaces of an extrusion punch.

6. An article of manufacture according to claim 1 in which said first and second series of surfaces define the external surface of a punch nib, said nib including a conically tapered point, said nib being disposed within a recess at one end of the punch body.

7. An article of manufacture according to claim 1 in which an enlarged bearing washer is provided between said two series of curved surfaces and the remainder of said body.

8. An article of manufacture according to claim 1 in which said first series of surfaces define convex ridges and said second series of surfaces define concave flutes, and a shoulder extending from the inner ends of said ridges and converging within said flutes toward the central axis of said body and in the direction toward the free end of said ridges, said shoulders creating a dome-shaped zone of stressed metal spaced toward said free end and away from the juncture between said hex-lobular surfaced portion and the remainder of said body portion.

9. A tool comprising a body including a portion having a first series of spaced apart, semicylindrical surfaces and a second series of semicylindrical surfaces alternating with the surfaces of said first series and merging tangentially therewith, the axes of curvature of said two series of surfaces extending substantially parallel with each other and with the central axis of said body;

the axes of curvature of said first series of surfaces being disposed between the respective corresponding surface and said central axis; and

the axes of curvature of said second series of surfaces being disposed on the opposite side of the respective corresponding surface with respect to said centrAl axis;

the cross section of said surfaces of said portion being of symmetrical, generally hex-lobular configuration;

the axes of curvature of said first series of surfaces being coextensive with the apices of a regular hexagon;

the invention being characterized in that;

a. the first series of surfaces being convex surfaces and having a radius of curvature of approximately 5 to 10 percent of the major diameter across said first series of surfaces;

b. said second series of surfaces defining concave flutes and having a radius of curvature more than twice as great as that of said first series of surfaces;

c. contiguous surface portions of said first and second series of surfaces defining a driving surface with a drive angle of from 10* to 20*, d. and a shoulder extending angularly outwardly from the bottom of each of the flutes defined by said second series of surfaces to the outermost points of said first series of surfaces where they merge with the remainder of said body.

10. A tool as defined in claim 9 in which the free end of the portion defined by said first and second series of semicylindrical surfaces is provided with a relatively flat, conical point and in which the corner between said conical surface and said semicylindrical surfaces is rounded.

11. A tool as described in claim 9 and in which each of said shoulders extend at an angle approximately 30* with respect to the central axis.

12. A tool for fluted hex-lobular heads comprising a body including a recessed portion having a first series of spaced apart, internal semicylindrical surfaces and a second series of internal semicylindrical surfaces alternating with the surfaces of said first series and merging tangentially therewith, the axes of curvature of said two series of surfaces extending substantially parallel with each other and with the central axis of said body;

the axes of curvature of said first series of surfaces being disposed between the respective corresponding surface and said central axis; and

the axes of curvature of said second series of surfaces being disposed on the opposite side of the respective corresponding surface with respect to said central axis;

the cross section of said surfaces of said portion being of symmetrical, generally hex-lobular configuration;

the axes of curvature of said first series of surfaces being coextensive with the apices of a regular hexagon;

the invention being characterized in that;

a. the first series of surfaces being concave surfaces and having a radius of curvature of approximately 5 to 10 percent of the major diameter across said first series of surfaces;

b. said second series of surfaces forming convex ribs having a radius of curvature more than twice as great as that of said first series of surfaces;

c. contiguous surface portions of said first and second series of surfaces defining a driving surface with a drive angle of from 10* to 20*;

d. and a shoulder extending angularly outwardly on the ribs defined by said second series of surfaces to the outermost ends of said ribs.

13. A fastener device comprising a shank portion, and a torque-transmitting head provided with a lateral surface at the end thereof opposite said shank portion comprising a plurality of outwardly extending equal-sized, equispaced, semicylindrical lobes disposed in circular array about said head with the circumferential extent of each such lobe being of the order of 20* to 25*;

wherein the centers of said lobes are defined by the apices of a regular hexagon in a plane perpendicular to the axis of said device, and wherein the lateral surface of said head between each of said lobes comprises an inwardly directed semicylindrical curved surface extending at least substantially to the side of said regular hexagon midway between the said lobes, the radius of curvature of said lobes being between 5 and 10 percent of the major diameter across said lobes, said inwardly directed, semicylindrical, curved surface having a radius at least twice as great as the radius of said lobes, and joining said lobes approximately tangentially and defining a substantial area of driving surface at the sides of said lobes with a driving angle of from 10* to 20*, said driving surface providing for deep torque engagement of said lobes over said substantial area for minimizing force concentration thereon when said device is driven, said driving surface including contiguous surface portions of both said lobes and said inwardly directed curved surfaces and said driving angle being defined as the angle between a line tangent to a point of contiguity of said surface portions and the radius of said head bisecting the lobe immediately adjacent said driving surface.

14. A fastener driver device comprising a torque-transmitting head, the lateral surface of said torque-transmitting head describing a plurality of equal-sized, equispaced, semicylindrical lobes having a radius of curvature between 5 and 10 percent of the major diameter across said lobes, said lobes being disposed in circular array with the circumferential extent of each such lobe being of the order of 20* to 25* and adapted to drive a complementally shaped fastener device, wherein the centers of said lobes are defined by the apices of a regular hexagon located in a plane perpendicular to the longitudinal axis of said device, said lobes being disposed on the opposite sides of said apices with respect to said axis, and wherein the lateral surface of said body between each of said lobes comprises a curved surface oppositely directed from the said lobes and extending at least substantially to a side of said regular hexagon midway between the apices thereof, said oppositely directed curved surface extending between points on respective lobes for including an appreciable cylindrical portion at the sides of said lobes forming a driving surface at a side thereof having a driving angle of from 10* to 20*, said driving surface including contiguous surface portions of both said lobes and said oppositely directed curved surfaces and said driving angle being defined as the angle between a line tangent to a point of contiguity of said surface portions and the radius of said torque-transmitting head bisecting the lobe immediately adjacent said driving surface, the difference between the maximum radial dimension of said lobes from the axis of said head and the minimum radial dimension of said oppositely directed surfaces from said axis being approximately 50 percent greater than the radius of said semicylindrical lobes.

15. The device according to claim 14 wherein said oppositely directed surface comprises a semicylindrical surface of larger radius of curvature than said lobes and which tangentially intersects said lobes at said driving surface, said oppositely directed semicylindrical surface extending at least substantially to the side of said hexagon midway between said lobes.

16. A fastener device comprising a threaded shank portion and a torque-transmitting head including a washer portion adjoining said shank portion, said torque-transmitting head where it extends beyond said washer portion having a lateral driving surface defining a plurality of outwardly extending equal-sized, equispaced, semicylindrical lobes disposed in circular array about the axis of said head with the circumferential extent of each such lobe being of the order of 20* to 25*, said lobes extending longitudinally of said head and parallel to the axis thereof, wherein the centers of said lobes are defined by the apices of a regular hexagon in a plane perpendicular to the axis of said device, and wherein the lateral surface of said head between each of said lobes comprises an inwardly directed semicylindrical curved surfAce extending at least substantially to the side of said regular hexagon midway between the said lobes, said inwardly directed, semicylindrical, curved surface having a radius greater than twice the radius of said lobes, and joining said lobes approximately tangentially, and retaining a substantial area of driving surface at the sides of said lobes with a driving angle of from 10* to 20*, and a shoulder extending angularly inwardly from said washer portion to a point approximately halfway up said curved surface from said washer portion, said driving surface including contiguous surface portions of both said lobes and said inwardly directed curved surfaces, and said driving angle being defined as the angle between a line tangent to a point of contiguity of said surface portions and the radius of said torque-transmitting head bisecting the lobe immediately adjacent said driving surface.

17. An article of manufacture as described in claim 1 in which the area of the cross section outwardly of the second series of surfaces and between the midpoints of adjacent ones of said first series of surfaces is approximately double the area of the cross section inwardly of said first series of surfaces between adjacent midpoints of said second series of surfaces.