Claims
- 1. A driver for applying torque to a fastener having a standard Phillips cross-shaped recess formed in the head of the fastener, the standard Phillips cross-shaped recess comprising four equally radially spaced recess wings having side surfaces and outer radial surfaces, the outer radial surfaces thereof converging toward a common point at a predefined standard wing angle relative to the axis of the fastener, the side surfaces of adjoining recess wings defining a predefined standard included angle that remains substantially constant from the bottom of said recess wings to the top of said recess, and wherein the sidewalls of said recess wings are angled at a predefined standard root angle relative to said axis;
- the driver having associated therewith an axis and including a bit portion symmetrical about any plane containing the axis of the driver and adapted for insertion into said recess comprising:
- four bit wings having side surfaces and radially outward facing surfaces, the radially outward facing surfaces converging at an angle relative to the axis of said bit portion substantially equal to said predefined standard wing angle, and wherein the side surfaces of adjoining bit wings define a root that is oriented relative to said axis at an angle substantially equal to said standard root angle, and further wherein said side surfaces of adjoining bit wings define an included angle that increases progressively in the axial direction from a first angle at least as great as said standard included angle adjacent the base of said bit wings to a second greater included angle at an axially spaced distance therefrom, such that when said bit portion is inserted into the recess of a standard Phillips-head fastener, initial contact is created between the recess and said bit portion on the side surfaces of said bit wings.
- 2. The driver of claim 1 wherein the contact area between the recess and said bit portion expands progressively radially outwardly from the initial area of contact as the torque levels applied by said driver to said fastener increase.
- 3. The driver of claim 1 wherein said radially outward facing surfaces of said bit wings have a substantially uniform width from the base of said bit wings to the end of said taper.
- 4. The driver of claim 1 wherein a gap exists radially inward from the initial area of contact between the roots of said bit portion and the opposing surfaces of said recess when said bit portion is fully inserted into said recess.
- 5. The driver of claim 1 wherein the base of said bit portion is truncated.
- 6. The driver of claim 1 wherein said bit portion is symmetrical about any plane containing the axis of the river.
- 7. The driver of claim 3 wherein a gap exists between said radially outward facing surfaces of said bit wings and the opposing outer radial surfaces of said recess wings when said bit portion is fully inserted into said recess.
- 8. A driver for a standard Phillips-head fastener having a cross-shaped recess formed in the head thereof in accordance with the Phillips-standard wing angle, root angle, and included angle dimensions, the driver including a bit portion adapted for insertion into said recess and comprising four bit wings having radially outwardly facing surfaces converging toward a common point at approximately the Phillips-standard wing angle, the bit portion comprising:
- generated side surfaces on said bit wings such that the side surfaces of adjoining bit wings define an included angle in a plane substantially normal to the axis of said bit portion that decreases in the axial direction from a first angle greater than the Phillips-standard included angle adjacent the base of said bit wings to a second angle greater than the Phillips-standard included angle adjacent the radially outer tip of said bit wings.
- 9. The driver of claim 8 wherein the included angle between the side surfaces of adjoining bit wings decreases progressively from said first angle to said second angle.
- 10. The driver of claim 7 wherein said driver has four bit wings and said bit wings are radially symmetrical such that equal levels of torque can be applied from said driver to the fastener in both rotational directions by all four bit wings.
- 11. The driver of claim 8 wherein said first angle is approximately equal to 119 degrees and said second angle is approximately equal to 110 degrees.
- 12. The driver of claim 8 wherein said bit wings define roots therebetween that are oriented relative to the axis of said bit at an angle substantially equal to the Phillips-standard root angle.
- 13. The driver of claim 12 wherein said bit portion is adapted to initially engage said recess at the side surfaces of said bit wings along lines of contact adjacent and substantially parallel to said roots.
- 14. The driver of claim 13 wherein a progressively increasing gap exists between the generated side surfaces of said bit wings and the corresponding side surfaces of said recess in a radially outward direction from said lines of contact when said bit portion is inserted into said recess.
- 15. The driver of claim 14 wherein the base of said bit portion is truncated.
- 16. The driver of claim 14 wherein said radially outward facing surfaces of said bit wings have a substantially uniform width.
- 17. The driver of claim 14 wherein the area of engagement between the recess and said bit expands progressively radially outwardly from said lines of contact as the torque levels applied by said driver to said fastener increases.
- 18. The driver of claim 14 wherein a gap exists between said radially outward facing surfaces of said bit wings and said opposing outer radial surfaces of said recess wings when said bit portion is fully inserted into said recess.
- 19. The driver of claim 14 wherein a gap exists radially inward from said lines of contact between the roots of said bit portion and the opposing surfaces of said recess when said bit portion is fully inserted into said recess.
- 20. A driver for a standard Phillips-head fastener having a cross-shaped recess formed in the head thereof defining recess wings having outer radial surfaces that are tapered toward a common point at a predefined standard wing angle relative to the axis of the fastener and sidewalls oriented at a predefined standard root angle relative to said axis such that the thickness of said recess wings expands in the axial direction from the bottom of the recess to the top of the recess; said driver including a bit portion adapted for insertion into said recess comprising:
- four bit wings having radially outward facing surfaces that are tapered toward a common point at an angle substantially equal to said standard wing angle relative to the axis of said bit portion and wherein the thickness of said bit wings adjacent the roots of said bit wings increases gradually in the axial direction at an angle approximately equal to said standard root angle but remains substantially constant along said tapered radially outward facing surfaces.
- 21. The driver of claim 20 wherein a gap exists between said radially outward facing surfaces of said bit wings and said opposing outer radial surfaces of said recess wings when said bit portion is fully inserted into said recess.
- 22. The driver of claim 20 wherein a gap exists radially inward from said lines of contact between the roots of said bit portion and the opposing surfaces of said recess when said bit portion is fully inserted into said recess.
- 23. The driver of claim 20 wherein the base of said bit portion is truncated.
- 24. The driver of claim 20 wherein said bit wings are radially symmetrical such that equal levels of torque can be applied by said driver to the fastener in both rotational directions by all four bit wings.
- 25. The driver of claim 20 wherein said bit wings define roots therebetween that are oriented relative to the axis of said bit portion at an angle substantially equal to said standard root angle.
- 26. The driver of claim 25 wherein the side surfaces of adjoining recess wings in the standard Phillips-head fastener define a predefined Phillips-standard included angle that remains substantially constant from the bottom of said recess to the top of said recess, and further wherein the side surfaces of said bit wings of the driver comprise generated surfaces that define an included angle in a plane substantially normal to said bit portion axis that progressively decreases in the axial direction from a first angle greater than said Phillips-standard included angle adjacent the base of said bit wings to a second angle smaller than said first angle but still greater than said Phillips-standard included angle adjacent the radially outer tips of said bit wings.
- 27. The driver of claim 26 wherein said bit portion is adapted to engage said recess when said bit portion is inserted into said recess at the generated side surfaces of said bit wings along lines of contact adjacent and substantially parallel to said roots.
- 28. The driver of claim 27 wherein the area of engagement between the recess and said bit portion expands progressively radially outwardly from said lines of contact as the torque levels applied by said driver to said fastener increase.
- 29. The driver of claim 26 wherein said first angle is approximately equal to 119 degrees and said second angle is approximately equal to 110 degrees.
- 30. A driver for a standard Phillips-head fastener having a cross-shaped recess formed to a defined depth in the head thereof, the driver having associated therewith an axis and including a bit portion adapted for insertion into said recess comprising:
- wing means symmetrical about any plane containing the axis of the river and having side surfaces defining roots therebetween for rotationally driving said fastener initially adjacent said roots along substantially the entire depth of said recess and progressively radially outward therefrom along said side surfaces as the torque levels applied by said driver to said fastener increase.
- 31. The driver of claim 30 wherein said wing means initially drive said fastener along lines of contact with said recess that are substantially parallel to said roots.
- 32. The driver of claim 30 wherein said wing means comprises four equally radially spaced bit wings defined by generated side surfaces that in turn define an included angle between adjoining bit wings that progressively increases in the axial direction from a first angle at least as great as the Phillips-standard included angle adjacent the base of the bit wings to a second greater included angle adjacent the radially outer tips of said bit wings.
- 33. The driver of claim 30 wherein said wing means comprises four equally radially spaced bit wings defined by generated side surfaces that in turn define an included angle between adjoining bit wings that progressively decreases in the axial direction from a first angle greater than the Phillips-standard included angle adjacent the base of said bit wings to a second angle smaller than said first angle but still greater than the Phillips-standard included angle adjacent the radially outer tips of said bit wings.
- 34. The driver of claim 33 wherein said first angle is approximately equal to 119 degrees and said second angle is approximately equal to 110 degrees.
- 35. The driver of claim 33 wherein the radially outwardly facing surfaces of said bit wings are tapered toward a common point at an angle relative to the axis of said bit portion substantially equal to the Phillips-standard wing angle.
- 36. The driver of claim 35 wherein said radially outward facing surfaces of said bit wings have a substantially uniform width.
- 37. The driver of claim 35 wherein the roots of said bit portion are oriented relative to said bit axis at an angle substantially equal to the Phillips-standard root angle.
- 38. The driver of claim 37 wherein the base of said bit portion is truncated.
- 39. The driver of claim 37 wherein a gap is exists between said radially outward facing surfaces of said bit wings and the opposing outer radial surfaces of said recess when said bit portion is fully inserted into said recess.
- 40. The driver of claim 37 wherein a gap exists between the root areas of said bit portion and the opposing surfaces of said recess when said bit portion is inserted into said recess.
- 41. A driver for a standard Phillips-head fastener having a cross-shaped recess formed in the head thereof, the driver having associated therewith an axis and including a bit portion symmetrical about any plane containing the axis of the driver and adapted for insertion into said recess comprising:
- wing means having generated side surfaces and defining roots therebetween for rotationally driving said fastener on said side surfaces in the same manner in both rotational directions.
- 42. The driver of claim 41 wherein said wing means is adapted to rotationally drive said fastener in both rotational directions initially adjacent said roots and progressively radially outward therefrom along said side surfaces as torque levels applied by said driver to said fastener increase.
- 43. The driver of claim 42 wherein said wing means initially engages said recess and drives said fastener along lines of contact adjacent and substantially parallel to said roots.
- 44. The driver of claim 43 wherein said wing means comprises four equally radially spaced bit wings defined by generated side surfaces that in turn define an included angle between adjoining bit wings that progressively decreases from a first angle greater than the Phillips-standard included angle adjacent the base of said bit wings to a second angle smaller than said first angle but still greater than the Phillips-standard included angle adjacent the radially outer tips of said bit wings.
- 45. The driver of claim 44 wherein said first angle is approximately equal to 119 degrees and said second angle is approximately equal to 110 degrees.
- 46. The driver of claim 44 wherein said bit wings have radially outwardly facing surfaces that are tapered toward a common point at an angle relative to the axis of said driver substantially equal to the Phillips-standard wing angle.
- 47. The driver of claim 46 wherein said radially outward facing surfaces of said bit wings have a substantially uniform width.
- 48. The driver of claim 47 wherein the roots of said bit portion are oriented relative to said driver axis at an angle substantially equal to the Phillips-standard root angle.
- 49. The driver of claim 48 wherein a gap exists between said radially outward facing surfaces of said bit wings and the opposing outer radial surfaces of said recess when said bit portion is fully inserted into said recess.
- 50. The driver of claim 48 wherein a gap exists between the root areas of said bit portion and the opposing surfaces of said recess when said bit portion is inserted into said recess.
- 51. The driver of claim 48 wherein the base of said bit portion is truncated.
- 52. A driver for applying torque to a fastener having a standard Phillips cross-shaped recess formed in the head of the fastener, the standard Phillips cross-shaped recess comprising four equally radially spaced recess wings having side surfaces and outer radial surfaces, the outer radial surfaces thereof converging toward a common point at a predefined standard wing angle relative to the axis of the fastener, the side surfaces of adjoining recess wings defining a predefined standard included angle that remains substantially constant from the bottom of said recess wings to the top of said recess, and wherein the sidewalls of said recess wings are angled at a predefined standard root angle relative to said axis;
- the driver having associated therewith an axis and including a bit portion symmetrical about any plane containing the axis of the driver and adapted for insertion into said recess comprising:
- four bit wings having side surfaces and radially outward facing surfaces, the radially outward facing surface converging at an angle relative to the axis of said bit portion substantially equal to said predefined standard wing angle, and wherein the side surfaces of adjoining bit wings define a root that is oriented relative to said axis at an angle substantially equal to said standard root angle, and further wherein said bit wings are configured such that when said bit portion is inserted into the recess of a standard Phillips-head fastener, initial contact is created between the recess and said bit portion on the side surfaces of each of said bit wings along lines of contact adjacent and substantially parallel to said roots with a gradually increasing gap formed between the side surfaces of said bit wings and the corresponding side surfaces of said recess wings in a radially outward direction from said lines of contact.
- 53. The driver of claim 52 wherein the side surfaces of adjoining bit wings define an included angle that progressively decreases in the axial direction from a first angle greater than said predefined standard included angle adjacent the base of said bit wings to a second angle smaller than said first angle but still greater than said predefined standard included angle adjacent the radially outer tips of said bit wings.
- 54. The driver of claim 52 wherein the contact area between the recess and said bit portion expands progressively radially outwardly from said lines of contact as the torque levels applied by said driver to said fastener increase.
- 55. The driver of claim 52 wherein said radially outward facing surfaces of said bit wings have a substantially uniform width from the base of said bit wings to the end of said taper.
- 56. The driver of claim 52 wherein a gap exists radially inward from said lines of contact between the roots of said bit portion and the opposing surfaces of said recess when said bit portion is fully inserted into said recess.
- 57. The driver of claim 54 wherein said bit wings are configured so that all four bit wings rotationally drive the fastener in the same manner in both rotational direction.
- 58. The driver of claim 55 wherein a gap exists between said radially outward facing surfaces of said bit wings and said opposing outer radial surfaces of said recess wings when said bit portion is fully inserted into said recess.
- 59. The driver of claim 52 wherein the base of said bit portion is truncated.
- 60. A driver for a standard Phillips-head fastener having a cross-shaped recess formed in the head thereof, the driver having associated therewith an axis and including a bit portion symmetrical about any plane containing the axis of the driver and adapted for insertion into said recess comprising:
- wing means having side surfaces and defining roots therebetween for rotationally driving said fastener in both rotational directions initially along lines of contact on said side surfaces adjacent and substantially parallel to said roots and over progressively radially outwardly expanding areas on said side surfaces as the torque levels applied by said driver to said fastener increase.
- 61. The driver of claim 60 wherein said wing means comprises four bit wings that are configured to rotationally drive the fastener in the same manner in both rotational directions.
- 62. The driver of claim 60 wherein said wing means comprises four equally radially spaced bit wings defined by generated side surfaces that in turn define an included angle between adjoining bit wings that progressively decreases from a first angle greater than the Phillips-standard included angle at the base of said bit wings to a second angle less than said first angle but still greater than the Phillips-standard included angle adjacent the radially outer tips of said bit wings.
- 63. The driver of claim 62 wherein said first angle is approximately equal to 119 degrees and said second angle is approximately equal to 110 degrees.
- 64. The driver of claim 62 wherein said wing means further has radially outwardly facing surfaces that are tapered toward a common point at an angle relative to the axis of said bit portion substantially equal to the Phillips-standard wing angle.
- 65. The driver of claim 64 wherein the roots of said bit portion are oriented relative to said bit axis at an angle substantially equal to the Phillips-standard root angle.
- 66. The driver of claim 65 wherein said cross-shaped recess has radially outward facing surfaces and further wherein a gap exists between said radially outward facing surfaces of said bit wings and the opposing outer radial surfaces of said recess when said bit portion is fully inserted into said recess.
- 67. The driver of claim 65 wherein a gap exists between the root areas of said bit portion and the opposing surfaces of said recess when said bit portion is inserted into said recess.
- 68. The driver of claim 65 wherein the base of said bit portion is truncated.
- 69. The method of applying torque to a standard Phillips-head fastener having a standard Phillips cross-shaped recess formed in the head thereof, including the steps of:
- inserting into said standard Phillips-head recess the bit portion of a driver having four radially symmetrical bit wings that are adapted to engage said recess along lines of contact on the side surfaces of said bit wings adjacent and substantially parallel to the roots of said adjoining bit wings, and
- rotating said driver so that torque is initially applied to said fastener along said lines of contact.
- 70. The method of claim 69 wherein each of said four bit wings drives the fastener in the same manner in both rotational directions.
- 71. The method of claim 69 further including the step of progressively expanding the areas of contact between said bit portion and said recess in a radially outward direction over said side surfaces of said bit wings as the level of torque applied by said driver to said fastener in a first rotational direction increases.
- 72. The method of claim 71 further including the step of progressively expanding the areas of contact between said bit portion and said recess in a radially outward direction over said side surfaces of said bit wings as the level of torque applied by said driver to said fastener in a second opposite rotational direction increases.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. application Ser. No. 270,000, filed Nov. 14, 1988, now abandoned.
The present invention relates to screwdriver bits and in particular to an improved screwdriver bit for Phillips-head fasteners that significantly reduces the "cam-out" experienced with a conventional screwdriver bit for Phillips-head fasteners.
Conventional Phillips-head fasteners and screwdrivers were originally developed to provide a fastening system that would facilitate efficient installation of fasteners on an assembly line. In particular, as compared to conventional slotted screws, the Phillips screw was designed to center quickly and easily on the screwdriver and permit more torque to be applied to the screw so that it would hold tighter than conventional slotted screws. In addition, it was expressly contemplated that, when applied by automated screwdrivers on an assembly line, the increasing torque applied to the Phillips screw would eventually cause the driver to pop out of the recess in the screw. In other words, the original Phillips-head design was intended to cause cam-out of the driver without damaging the screw head. It is, of course, this tendency of the Phillips-head design to cause cam-out of the driver, that is a principal source of irritation for craftsmen and ordinary consumers alike.
It is, therefore, the primary object of the present invention to provide an improved screwdriver bit that is compatible with the standard Phillips-head geometry and, therefore, is useable with standard Phillips-head fasteners and yet is designed to significantly reduce the tendency of the driver to cam-out of the recess in the screw head.
In addition, it is an object of the present invention to provide an improved driver for Phillips-head screws that enables the application of significantly greater torque loads to a standard Phillips-head screw with minimum distortion of the shape of the recess in the screw head.
Furthermore, it is an object of the present invention to provide an improved driver for Phillips-head screws that enables the application of significantly greater torque loads to a standard Phillips-head screw equally in both rotational directions.
It is also an object of the present invention to provide such an improved Phillips-type screwdriver bit that retains the other benefits of the standard Phillips system, namely the automatic centering of the bit on the fastener, the "fit" of bit to the fastener, and the ability to hold a fastener on the end of the bit prior to installation.
Additional objects and advantages of the present invention will become apparent from a reading of the following detailed description of the preferred embodiment which makes reference to the drawings in which:
US Referenced Citations (27)
Foreign Referenced Citations (8)
| Number |
Date |
Country |
| 8021734 |
|
DEX |
| 1330358 |
May 1962 |
FRX |
| 2383350 |
Jun 1978 |
FRX |
| 2469250 |
Dec 1979 |
FRX |
| 813571 |
|
GBX |
| 901417 |
|
GBX |
| 1065348 |
|
GBX |
| 1102404 |
|
GBX |
Non-Patent Literature Citations (1)
| Entry |
| The Wall Street Journal, article "Does Henry Phillips, Bane of Handymen, Really Rest in Peace", Sep. 15, 1988. |
Continuation in Parts (1)
|
Number |
Date |
Country |
| Parent |
270000 |
Nov 1988 |
|
Patent Grant
4998454
