Patent Description:
Fasteners are used in numerous applications to attach various components together. Typically, a fastener has at least a threaded portion and one or more bearing surfaces attached thereto. The bearing surfaces are designed to receive torque from a tool, such as a socket or wrench, which is used to tighten or loosen the fastener. In a conventional fastener, such as a nut, the fastener may have internal threads and six bearing surfaces oriented in a hexagon shape around the internal threads. However, other fasteners may have external threads, such as bolts and screws.

Document <CIT> discloses an assembly improving, lower mass fastener head that is easier to handle and reduces the amount of material that is required in manufacturing the fastener comprises three lugs at multiples of <NUM> degrees around an axis of a threaded body. Those portions of a hex head that are not necessary for application and transmission of torque, nor necessary to resist axial loading, nor necessary to axially stabilize the fastener head within current driving tooling may be removed. Compatibility with existing hex head tools is maintained while improving handling of the fastener by an assembler and reducing material used in the fastener head.

The most common shape of a tool to apply torque to threaded fasteners is a hexagon or hexagon-like geometry socket. Accordingly, many fasteners have a hexagon shape. Applying torque with a hexagon or hexagon-like geometry socket to fasteners creates contact between the socket and fastener at six places, namely, at or near each corner of the hexagon fastener. In contrast, a standard open-end wrench applies torque to fasteners at two places, namely, at opposite corners of the hexagon fastener. This common usage of open-end wrenches with hexagon fasteners demonstrates the strength that exists in hexagon fasteners at the torque bearing surfaces.

To meet ever increasing global demands for energy efficiency, automobile manufacturers have expressed the need to reduce the mass of vehicles to help meet government requirements for increasing fuel efficiency. The inventor believes the design of fasteners can be improved to lower weight, while maintaining the highest industry standards for durability and function.

A fastener according to the invention is set out in the appended set of claims.

A standard hexagon shaped fastener includes a torque bearing surface with six sides that intersect at the six corners of the hexagon to create six edges between the six sides. The angle at each corner is approximately <NUM> degrees.

Referring now to the figures, <FIG> shows an embodiment of an improved fastener. Fastener <NUM> has a threaded portion <NUM>. Threaded portion <NUM> may surround an opening extending along the axial length of fastener <NUM> (into the page of <FIG>). Fastener <NUM> may be a nut or any other fastener with internal threads. Alternatively, fastener <NUM> may be a bolt or any other fastener with external threads (not shown). Threaded portion <NUM> may include internal threads with a major diameter <NUM> shown with a dotted line.

Fastener <NUM> may include a torque bearing portion <NUM>. The torque bearing portion <NUM> may extend the entire axial length of fastener <NUM> or may only extend along part of the axial length of fastener <NUM>. Bearing portion <NUM> may include three torque bearing surfaces <NUM>, <NUM>, <NUM> that may be designed to receive torque from a tool, such as a socket or wrench, and transmit torque to the threaded portion <NUM>.

Each torque bearing surface <NUM>, <NUM>, <NUM> may include two torque bearing sides with an edge <NUM>, <NUM>, <NUM> between the sides. Torque bearing surface <NUM> may include torque bearing sides 108a and 108b with edge <NUM> between the sides. Torque bearing surface <NUM> may include torque bearing sides 110a and 110b with edge <NUM> between the sides. Torque bearing surface <NUM> may include torque bearing sides 112a and 112b with edge <NUM> between the sides. The height of each torque bearing side 108a, 108b, 110a, 110b, 112a, 112b may be the height of the bearing portion <NUM> in an axial direction. Each torque bearing side 108a, 108b, 110a, 110b, 112a, 112b may be designed to receive torque from a tool, such as a socket or wrench, and transmit torque to the threaded portion <NUM> depending if the tool is tightening or loosening fastener <NUM>. For example, if the tool is tightening fastener <NUM>, torque bearing sides 108a, 110a, 112a may receive torque from the tool and transfer the torque to the threaded portion <NUM>. Whereas if the tool is loosening fastener <NUM>, torque bearing sides 108b, 110b, 112b may receive torque from the tool and transfer the torque to the threaded portion <NUM>. The torque bearing side that receives and transfers torque when fastener <NUM> is being tightened or loosened may be switched depending on the direction of the threads in threaded portion <NUM>.

Edges <NUM>, <NUM>, <NUM> may extend the entire axial length of bearing portion <NUM>. Edges <NUM>, <NUM>, <NUM> may be located at the mid-point of torque bearing surface <NUM>, <NUM>, <NUM>, respectively, such that the widths of each corresponding torque bearing side 108a, 108b, 110a, 110b, 112a, 112b are the same. For example, the widths of torque bearing sides 108a and 108b may be the same. Alternatively, the widths of any or all of the torque bearing sides may be different than any or all of the other torque bearing sides.

Fastener <NUM> may be designed and shaped to be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. Accordingly, the angle at edges <NUM>, <NUM>, <NUM> where the torque bearing sides intersect may be approximately <NUM> degrees to match the angle of a standard hexagon shaped socket. Additionally, the edges <NUM>, <NUM>, <NUM> may be equally spaced around the longitudinal axis of fastener <NUM> to match a standard hexagon shaped socket.

Bearing portion <NUM> may also include three non-torque bearing surfaces <NUM>, <NUM>, <NUM>. The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may not be intended to receive and transfer torque from a tool to the threaded portion <NUM>. The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may, however, incidentally receive and transfer torque from a tool to the threaded portion <NUM> even if the non-torque bearing surfaces <NUM>, <NUM>, <NUM> are not intended to do so.

The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be located adjacent to and between the torque bearing surface <NUM>, <NUM>, <NUM> such that torque bearing surface <NUM>, <NUM>, <NUM> are not adjacent to each other. The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be flat. The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may extend the entire axial length of bearing portion <NUM>.

Fastener <NUM> may have a reduced mass compared to a standard fastener of similar size designed for the same application as fastener <NUM>. The reduce mass of fastener <NUM> may be due to the presence of the non-torque bearing surfaces <NUM>, <NUM>, <NUM> in place of torque bearing corners that would be located on standard fasteners. For example, the mass reduction of fastener <NUM> over an M12 x <NUM> thread x <NUM> across flats x <NUM> high standard hexagon nut would be between <NUM>-<NUM>%, and preferable approximately <NUM>% plus or minus <NUM>%. In grams mass, this is a reduction from <NUM> to <NUM> grams.

<FIG> shows another embodiment of an improved fastener. Fastener <NUM> may have the same features and components as fastener <NUM>. Fastener <NUM> may include angles at edges <NUM>, <NUM>, <NUM> that are different than <NUM> degrees, but fastener <NUM> may still be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. For example, the angles at edges <NUM>, <NUM>, <NUM> of fastener <NUM> may be <NUM> to <NUM> degrees.

The increased angles at edges <NUM>, <NUM>, <NUM> of fastener <NUM>, in comparison to the angles of fastener <NUM>, may be caused by recessed regions 208a_r, 208b_r, 210a_r, 210b_r, 212a_r, 212b_r of the torque bearing sides 208a, 208b, 210a, 210b, 212a, 212b adjacent to edges <NUM>, <NUM>, <NUM>, as shown by the space within the dotted line in <FIG>. The recessed regions 208a_r, 208b_r, 210a_r, 210b_r, 212a_r, 212b_r of the torque bearing sides are disposed inwardly from an imaginary plane defined by the remainder of the torque bearing sides 208a, 208b, 210a, 210b, 212a, 212b. The recessed bearing surfaces and increased angle at edges <NUM>, <NUM>, <NUM> may reduce deformation of the torque bearing surface <NUM>, <NUM>, <NUM> at edges <NUM>, <NUM>, <NUM> compared to fastener <NUM> because the initial contact between a standard socket tool and the recessed regions 208a_r, 208b_r, 210a_r, 210b_r, 212a_r, 212b_r of the torque bearing sides occurs along a generally parallel plane to the initial contact area, which is significantly larger than the initial contact area with fastener <NUM>. As a result, the initial pressure generated by the applied torque is less and may cause less deformation of the fastener <NUM>. The recessed bearing surfaces and increased angle at edges <NUM>, <NUM>, <NUM> are described in <CIT>.

<FIG> shows another embodiment of an improved fastener. Fastener <NUM> may have the same features and components as fasteners <NUM> and <NUM>. Fastener <NUM> may include modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>, as compared to fasteners <NUM> and <NUM>. Fastener <NUM> may still be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. In fastener <NUM>, torque bearing surfaces <NUM>, <NUM>, <NUM> and non-torque bearing surfaces <NUM>, <NUM>, <NUM> are curved and are smoothly contoured into each other in order to reduce the mass of fastener <NUM>. As shown in <FIG>, the torque bearing surfaces <NUM>, <NUM>, <NUM> adjacent to non-torque bearing surfaces <NUM>, <NUM>, <NUM> have been reduced in size such that there is a smooth transition to the non-torque bearing surfaces <NUM>, <NUM>, <NUM> instead of a sharp corner, as in <FIG>. Similarly, non-torque bearing surfaces <NUM>, <NUM>, <NUM> have been curved to smoothly transition to the torque bearing surfaces <NUM>, <NUM>, <NUM>.

Fastener <NUM> may have a reduced mass compared to a standard fastener of similar size due to the modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>. For example, the mass reduction of fastener <NUM> may be approximately <NUM>% compared to a standard fastener of similar size designed for the same application as fastener <NUM>. The size reduction and/or curvature of torque bearing surfaces <NUM>, <NUM>, <NUM> and non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be adjusted to increase or decrease the mass reduction of fastener <NUM>.

<FIG> shows another embodiment of an improved fastener. Fastener <NUM> may have the same features and components as fasteners <NUM>, <NUM>, and <NUM>. Similar to fastener <NUM>, fastener <NUM> may include modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>, as compared to fasteners <NUM> and <NUM>. Fastener <NUM> may still be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. In fastener <NUM>, torque bearing surfaces <NUM>, <NUM>, <NUM> and non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be angled toward each other in order to reduce the mass of fastener <NUM>. As shown in <FIG>, the torque bearing surfaces <NUM>, <NUM>, <NUM> adjacent to non-torque bearing surfaces <NUM>, <NUM>, <NUM> have been reduced in size and angled such that there is a smooth transition to the non-torque bearing surfaces <NUM>, <NUM>, <NUM> instead of a sharp corner, as in <FIG>. Similarly, non-torque bearing surfaces <NUM>, <NUM>, <NUM> have been angled to smoothly transition to the torque bearing surfaces <NUM>, <NUM>, <NUM>. Non-torque bearing surfaces <NUM>, <NUM>, <NUM> may include edges <NUM>, <NUM>, <NUM> as a result of the angles of non-torque bearing surfaces <NUM>, <NUM>, <NUM>.

Fastener <NUM> may have a reduced mass compared to a standard fastener of similar size due to the modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>. The mass reduction of fastener <NUM> may be less than the mass reduction of fastener <NUM> due to the angles of torque bearing surfaces <NUM>, <NUM>, <NUM> and non-torque bearing surfaces <NUM>, <NUM>, <NUM>. The angles of torque bearing surfaces <NUM>, <NUM>, <NUM> and non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be adjusted to increase or decrease the mass reduction of fastener <NUM>.

<FIG> shows another embodiment of an improved fastener. <FIG> includes different views of fastener <NUM>. <FIG> is a top view of fastener <NUM>. <FIG> are side views of fastener <NUM>. <FIG> is an elevation view of fastener <NUM>. Fastener <NUM> may have the same features and components as fasteners <NUM>, <NUM>, and <NUM>. The dimensions shown in <FIG> are exemplary and may be adjusted to meet the design requirements of the application of fastener <NUM>. Fastener <NUM> may include a threaded portion <NUM> with internal threads with a major diameter <NUM> shown with a dotted line in <FIG>. Fastener <NUM> may include a bearing portion <NUM> with three torque bearing surfaces <NUM>, <NUM>, <NUM> that may be designed to receive torque from a tool, such as a socket or wrench, and transmit torque to the threaded portion <NUM>. Similar to fastener <NUM>, fastener <NUM> may include modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>, as compared to fasteners <NUM> and <NUM>.

Similar to fastener <NUM>, each torque bearing surface <NUM>, <NUM>, <NUM> may include two torque bearing sides with an edge <NUM>, <NUM>, <NUM> between the sides. Fastener <NUM> may be designed and shaped to be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. Accordingly, the angle at edges <NUM>, <NUM>, <NUM> where the torque bearing sides intersect may be approximately <NUM> degrees to match the angle of a standard hexagon shaped socket. Additionally, the edges <NUM>, <NUM>, <NUM> may be equally spaced around the longitudinal axis of fastener <NUM> to match a standard hexagon shaped socket.

Fastener <NUM> may have a reduced mass compared to a standard fastener of similar size due to the presence of the non-torque bearing surfaces <NUM>, <NUM>, <NUM> in place of torque bearing corners that would be located on standard fasteners. For example, the mass reduction of fastener <NUM> over an M12 x <NUM> thread x <NUM> across flats x <NUM> high standard hexagon nut would be approximately <NUM>%. In grams mass, this is a reduction from <NUM> to <NUM> grams.

<FIG> shows opening <NUM> extending through the axial length of fastener <NUM>. <FIG> shows threaded portion <NUM> with internal threads with a major diameter <NUM> shown with a dotted line. <FIG> show that fastener <NUM> may include an abutment portion <NUM> with an abutment surface <NUM> designed to make contact with the surface of another component to be fastened, such as a washer or a wheel, depending on the application of fastener <NUM>. <FIG> shows edges <NUM>, <NUM> on bearing portion <NUM>.

<FIG> shows another embodiment of an improved fastener. Fastener <NUM> includes nut <NUM> and cap <NUM>. Nut <NUM> may have the same features and components as fasteners <NUM>, <NUM>, and <NUM>. Nut <NUM> may include a threaded portion <NUM> with internal threads with a major diameter <NUM> shown with a dotted line in <FIG>. Nut <NUM> may include a bearing portion <NUM> with three torque bearing surfaces <NUM>, <NUM>, <NUM>, as shown in <FIG>, that may be designed to receive torque from a tool, such as a socket or wrench, and transmit torque to the threaded portion <NUM>. Nut <NUM> may also include three non-torque bearing surfaces <NUM>, <NUM>, <NUM>. The non-torque bearing surfaces <NUM>, <NUM>, <NUM> may be located adjacent to and between the torque bearing surface <NUM>, <NUM>, <NUM> such that torque bearing surface <NUM>, <NUM>, <NUM> are not adjacent to each other. Similar to fastener <NUM>, nut <NUM> may include modified torque bearing surfaces <NUM>, <NUM>, <NUM> and modified non-torque bearing surfaces <NUM>, <NUM>, <NUM>, as compared to fasteners <NUM> and <NUM>.

Cap <NUM> may surround the upper portion of nut <NUM>, including bearing portion <NUM> and the torque bearing surface <NUM>, <NUM>, <NUM> and the non-torque bearing surfaces <NUM>, <NUM>, <NUM>. Cap <NUM> may fit tightly around nut <NUM>. Accordingly, cap <NUM> may include similar torque bearing surfaces and non-torque bearing surfaces. Cap <NUM> may be crimped around nut <NUM>. Cap <NUM> and its attachment to nut <NUM> is described in <CIT>.

Similar to fasteners <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, fastener <NUM> may be driven by standard socket tools, such as a hexagon socket or a <NUM> point configuration socket. Fastener <NUM> may have a reduced mass compared to a standard fastener of similar size due to the presence of the non-torque bearing surfaces <NUM>, <NUM>, <NUM> in place of torque bearing corners that would be located on standard fasteners.

Claim 1:
A fastener comprising
a threaded portion; and
a bearing portion, wherein the bearing portion comprises:
exactly three bearing surfaces designed to receive torque from a tool and transmit torque to the threaded portion, wherein each bearing surface includes two adjacent sides with an edge disposed therebetween, the two adjacent sides being substantially planar and intersecting at the edge at an angle to form a point at each of the three bearing surfaces; and
three non-bearing surfaces (<NUM>, <NUM>, <NUM>), wherein each of the three non-bearing surfaces (<NUM>, <NUM>, <NUM>) has a convex curve extending continuously between two of the three bearing surfaces