Drive spike

Abstract

A fastener includes an elongated shank having a head formed at the first end of the shank, where the head has an outer surface and the head extends radially outwardly. The fastener also includes at least one helical thread portion extending along at least a portion of the shank and a substrate gripping portion extending along at least a portion of the shank between the head and the at least one helical thread portion. The substrate gripping portion includes at least one gripping member extending radially outwardly from the longitudinal axis.

Description

FIELD OF THE INVENTION

The present invention relates to fasteners. In particular, the present invention relates to a drive spike for driving into a substrate and preventing inadvertent removal of the drive spike from the substrate.

BACKGROUND

Many types of fasteners are known in the art for firmly holding a variety of components together. For example, railroad drive spikes are used to hold steel rails to wooden ties. Drive spikes may also be used to hold together bridges, trestles, wooden piers, and docks.

Typically, for railways, the steel rails have mounting flanges adapted to mate with metallic plates. The metallic plates also contact the wooden ties and are adapted receive drive spikes to secure the rails to the ties. The spikes are inserted through openings or recesses in the metal plate and driven into the wooden ties. Thus, the steel rails are secured to the wooden ties via the metal plates and the drive spikes.

In use, the drive spikes eventually loosen from the wooden ties as a result of events such as repeated train crossings and environmental conditions. The weight and vibrations from the passing trains cause the spikes to loosen and enlarge the entry holes within the wooden ties. Environmental conditions such as humidity, temperature changes, rain, snow, etc. may also cause the drive spikes to become loosed within the wooden ties. Additionally, vandals may purposely loosen or remove the drive spikes. As the drive spikes become loose, the holes into which the drive spikes are inserted in the wooden ties enlarge. The enlarged holes then become further exposed to environmental conditions, causing the wood to decay more quickly.

Tightening or replacement of the drive spikes is often difficult and costly. Removal of a drive spike may cause further destruction to the wooden tie making the replacement of the drive spike nearly impossible. Once the drive spike is loosened and or the wood becomes damaged, the entire wooden tie often requires replacement in order to provide a steel rail that is securely fastened to the wooden tie.

Similar to the railway example, the bridge, trestle, pier and dock drive spike connections are also subject to vibrational and environmental stresses, as well as vandalism, that cause unwanted loosening of the drive spikes within the substrate. Once the drive spike loosens, the substrate into which the spike is driven usually must be replaced in order to securely fasten the bridge, trestle, etc. to the substrate. Replacement of the drive spike itself is generally insufficient to securely fasten objects to the substrate. The enlarged hole in the substrate causes the substrate to become more quickly degraded and thus prevents the drive spike from securely gripping the substrate.

Therefore, it is an object of the present invention to provide a drive spike that securely fastens an object to a substrate, such as wood, and prevents inadvertent loosening or removal of the drive spike from the substrate, thus further reducing the requirement for replacement of the substrate due to damage caused by the insecure fastening of an object to a substrate.

BRIEF SUMMARY

In order to alleviate one or more shortcomings of the prior art, a drive spike is provided herein.

In one aspect of the present invention, a fastener is provided. The fastener includes an elongated shank extending along a longitudinal axis, a first end and a second end; a head formed at the first end of the shank, where the head extends radially outwardly from the longitudinal axis. The fastener also includes at least one helical thread portion extending along at least a portion of the shank; and a substrate gripping portion extending along at least a portion of the shank, the substrate gripping portion being between the head and the at least one helical thread portion, the substrate gripping portion including at least one gripping member extending radially outwardly from the longitudinal axis.

In another aspect of the present invention, a fastener is provided. The fastener includes an elongated shank having a longitudinal axis and a head formed at a first end of the shank, the head including a polygonally shaped outer surface. The fastener also includes a substrate gripping portion extending along at least a portion of the shank between the head and a second end of the shank where the substrate gripping portion includes at least one gripping member extending radially outwardly from the longitudinal axis. The at least one gripping member is polygonally shaped.

In another aspect of the present invention, a fastener is provided. The fastener includes an elongated shank having a head portion formed at a first end of the shank, where the head portion is adapted to be gripped by a tool. A plurality of protrusions extend radially outwardly from the shank, the plurality of protrusions extending between the head portion and a second end of the shank. The fastener also includes a helical thread portion extending axially along at least a portion of the shank, extending between the plurality of protrusions and the second end.

Advantages of the present invention will become more apparent to those skilled in the art from the following description of the preferred embodiments of the invention which have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a first embodiment of a drive spike in accordance with the present invention;

FIG. 2 is a top plan view of FIG. 1;

FIG. 3 is a partial view of FIG. 1;

FIG. 4 is a side elevational view of another embodiment in accordance with the present invention;

FIG. 5A is a side elevational view of a second embodiment in accordance with the present invention;

FIG. 5B is a side elevation view of FIG. 5A;

FIG. 6 is a top plan view of FIG. 5A;

FIG. 7 is a sectional view through line A-A of FIG. 5A; and

FIG. 8 is a sectional view through line B-B of FIG. 5A.

DETAILED DESCRIPTION OF THE DRAWINGS AND THE PRESENTLY PREFERRED EMBODIMENTS

A first embodiment of the present invention is shown in FIG. 1 as a drive spike 10 having an elongated shank 20, a head 22 at a first end 24 of the shank 20 and a tip 26 at a second end 28 of the shank 20. The shank 20 further comprises a longitudinal axis 30.

The head 22 further comprises an annular flange 32 that extends radially from the shank 20. As shown in FIG. 1, the flange 32 is slightly tapered in a countersunk formation, the flange 32 being widest toward the first end 24 and tapering inward in the direction of the second end 28. The head 22 further comprises a protrusion 36 that extends from the first end 24 of the shank 20. The protrusion 36 may be hemispherical in shape and adapted to be engaged by a striking tool to drive the fastener 10 into a substrate (not shown). The protrusion 36 is adapted to receive significant force and is further adapted to deform as a result of the striking force.

The head 22 also comprises an outer surface 38 adapted to be engaged by a gripping tool such as a wrench or a socket that may be used to apply torque to the fastener 10 to drive the fastener into the substrate. Preferably, the outer surface 38 may be polygonally shaped. However, the outer surface 38 may be any shape that may be used with a variety of tools. Alternatively, the outer surface 38 does not need to be engaged to drive the fastener 10 into the substrate. For example, a hole may be pre-drilled in the substrate and the fastener 10 may be driven into the substrate using a striking tool to strike the protrusion 36 of the head 22 and thereby insert the fastener 10 into the substrate.

As shown in FIG. 2, the annular flange 32 extends radially from the longitudinal axis 30 of the fastener 10. In a preferred embodiment, the annular flange 32 extends beyond the circumference of the shank 20. The flange 32 may provide further protection from loosening by providing a seal over the insertion hole in the substrate. The flange 32 may remain above and abut the top surface of the substrate. When the flange 32 abuts the top surface of the substrate, the drive spike 10 may be removed from the substrate, for example using a crowbar. Alternatively, the flange 32 may be countersunk into the substrate and the inward taper may be adapted to inhibit moisture from entering the hole in the substrate once the flange 32 has been sunk into the substrate. As shown in the embodiment in FIG. 2, the protrusion 36 comprises a ring on the first end 24 and the outer surface 38 comprises a square.

In the embodiment of the present invention shown in FIG. 1, the shank 20 further comprises a smooth cylindrical section 40, having a circumference 41, extending from the flange 32 toward the second end 28.

The shank 20 further comprises a plurality of annular grooves 42 cut into the shank 20 defining a plurality of annular rings 44. The plurality of annular rings extends from the cylindrical section 40 toward the second end 28 of the shank 20. The plurality of annular rings 44 taper inwardly as defined by the plurality of grooves 42. As shown, the plurality of annular rings 44 extend radially from the longitudinal axis 30 and the plurality of annular rings 44 extend to a circumference 46 preferably to the same extent as the circumference 41 of the cylindrical section 40. In the embodiments shown in FIGS. 1 and 3, the plurality of annular rings 44 comprises five annular rings and five grooves 42 being equally dimensioned. However, one skilled in the art will recognize that the number and dimension of the plurality of annular rings 44 may vary. For example, the plurality of annular rings 44 may have one or more of the plurality of annular rings 44 having a circumference 46 extending further from the longitudinal axis than the circumference 41 of the cylindrical section 40.

The plurality of annular rings 44 are adapted to secure the fastener 10 within the substrate. For example, when the shank 20 is inserted into a wooden substrate, the plurality of annular rings 44 is adapted to bite into the wooden substrate thus inhibiting the loosening or purposeful removal of the shank 20 from the wooden substrate once the annular rings 44 have bitten into the wood. The specific dimensions, as shown in the embodiments in FIGS. 1 and 3, preferably include the diameter of each ring 44 tapering from about 15/16 inches to about 13/16 inches. 15/16 inches is also the maximum diameter of the helical thread 48 at points 50a and 50b. The diameter of the flange 32 is about 2 inches. The overall dimensions of the preferred embodiment shown in FIG. 3 are 7/8 inches by 6½ inches. Of course, other dimensions for each of the dimensions described herein may be used and remain within the scope of the invention.

The shank 20 further comprises at least one helical flute thread 48. The at least one thread 48 extends from the plurality of annular rings to the tip 26. The angle at the end of the at least one thread 48 of the tip 26 may be about 20° to about 35°, more preferably about 25° to about 30°. In a preferred embodiment, the at least one thread 48 comprises a circumference 50 that is coplanar with the circumference 41 of the cylindrical section 40. The at least one thread 48 may be any type of thread commonly known to one of skill in the art. In the preferred embodiment, this is a 4-flute thread.

A second embodiment is shown in FIG. 4 as a drive spike 110 having an alternative head 122. A shank 120 and a cylindrical section 140 of the drive spike 110 are similar to the shank 20 and the cylindrical section 40, respectively, described above.

The head 122 further comprises an annular flange 133 that extends radially from the shank 120. The flange 133 includes a beveled annular surface 134. Preferably the diameter of the flange 133 is about 1½ inches. The head 122 further includes a protrusion 136 similar to the protrusion 36 described above.

The head 122 also comprises an axial extension 137 having an outer surface 138 adapted to be engaged by a gripping tool. The extension 137 includes a recessed annular section 139, preferably having a diameter of about 5/8 inches. The drive spike 110 may be driven into the substrate as described above.

A third embodiment is shown in FIGS. 5-8 as drive spike 210. The drive spike 210 includes an elongated shank 220, a head 222 at a first end 224 of the shank 220 and a tip 226 at a second end 228 of the shank 220. The shank 220 further comprises a longitudinal axis 230. The length and diameter of the drive spike 210 are not critical and may be varied as will be understood by one of skill in the art. Preferred lengths and diameters are included in the discussion below and are not meant to limit the present invention.

The head 222 includes a protrusion 236 that extends from the first end 224 of the shank 220. The protrusion 236 may be hemispherical in shape and adapted to be engaged by a striking tool to drive the drive spike 210 into a substrate (not shown). The protrusion 236 is adapted to receive significant force and is further adapted to deform as a result of the striking force. Preferably, the protrusion 236 is centered on the first end 224 of the head 220 and extends out from the first end 224 about 1/8 inch.

The head 222 includes an outer surface 238 adapted to be engaged by a gripping tool such as a wrench or a socket that may be used to apply torque to the drive spike 210 to drive the fastener into the substrate. As shown in FIG. 6, the shape of the outer surface 238 of the head 222 is preferably a polygon, more preferably a square such that a tool may engage the outer surface 238. For example, as shown in FIG. 6, the head 222 may have a square cross sectional shape having sides extending radially outwardly from the longitudinal axis about 1⅜ inches. One of skill in the art will understand that any shape and size of the head may be used and the shape and size of the outer surface 238 may be adapted for engagement with a tool. Alternatively, the outer surface 238 does not need to be engaged to drive the drive spike 210 into the substrate. For example, a hole may be pre-drilled in the substrate and the drive spike 210 may be driven into the substrate using a striking tool to strike the protrusion 236 of the head 222 and thereby insert the drive spike 210 into the substrate. As shown in FIG. 5, the head 222 may include a recess 235 necked in and defined around the perimeter of the head 222.

The head 222 extends radially outwardly from the longitudinal axis 230 of the drive spike 210. In a preferred embodiment, the head 222 extends beyond the circumference of the shank 220. The head 222 may provide further protection from loosening by providing a seal over the insertion hole in the substrate. A portion of the head 222 may remain above and abut the top surface of the substrate. When the head 222 abuts the top surface of the substrate and the recess 235 is exposed, the drive spike 210 may be removed from the substrate, for example using a crowbar. Alternatively, the head 222 may be countersunk into the substrate and be adapted to inhibit moisture from entering the hole in the substrate once the head 222 has been sunk into the substrate.

In the embodiment of the present invention shown in FIG. 5, the shank 220 further comprises a smooth cylindrical section 240, having a first reduced diameter 241, extending from the head 222 toward the second end 228. The shank 220 further includes a portion 244 having at least one elongated protrusion 245 extending outwardly from the portion 244 and adapted for gripping the substrate into which the drive spike 210 is inserted. The portion 244, including the protrusions 245 has a second reduced diameter 261 as shown in FIG. 7. Preferably, the protrusions 245 form elongated rectangular protrusions extending along the longitudinal axis 230 and around a circumference 247 of the shank 220. Each protrusion also may have a slightly rounded cross-sectional profile as shown in FIG. 7. For example, the protrusions 245 may have a width of about 1/8 inch and a length of about ½ inch. As shown in FIG. 7, a plurality of protrusions 245 may extend from the portion 244 and the protrusions 245 may be equidistantly spaced apart around the circumference of the portion 244 or alternatively, non-uniformly spaced apart. Alternative shapes and sizes for the protrusions 245 may also be used as will be understood by one of skill in the art. Preferably, the diameter 261 of the portion 244 has essentially the same length as the diameter 241 of the cylindrical section 240 and a diameter 250 of a helical thread discussed below. Additional diameters 241, 250, 261 are possible within the scope of the present invention and the diameters 241, 250, 261 need not be the same length.

The shank 220 may further include at least one helical flute thread 248 extending from the portion 244 towards the second end 228. A sectional view of the shank 220 through the line B-B is shown in FIG. 8. Preferably, the at least one thread 248 has the outer diameter 250 that is coextensive with the diameter 241 of the cylindrical section 240 and the diameter extending across the protrusions 245 of the portion 244 as shown in FIG. 7. For example, the diameters 241, 250 and 261 may be about 5/16 inch. Of course, other diameters for the sections of the shank 220 are possible. The at least one thread 48 may be any type of thread commonly known to one of skill in the art. In the preferred embodiment, this is a 4-flute thread. An end portion 266 of the shank 220 extends from the at least one helical flute thread 248. Preferably the end portion 266 has a diameter 268 that is smaller than the diameter 250 of the helical flute thread 248. The tip 226 may be any shape, including blunt and pointed. As shown in FIG. 8, and similar to the embodiments shown in FIGS. 1-4, each helical turn 270 of the thread 248 is preferably about ½ inch, although any width may be used. The depth 272 of the thread protruding from the shank 220 is preferably about 1/8 inch, although any depth may be used with the present invention.

As discussed above, the specific dimensions are exemplary and are not intended to be limiting. As will be understood by one of skill in the art, other dimensions for each of the dimensions described herein may be used and remain within the scope of the invention. The overall dimensions of the drive spike 210 are preferably 5/16×7½ inches where the head 222 is about 1 inch in length and may include a recess 235 extending about ⅜ in length and the recess 235 being located about 3/8 inch from the first end 224 of the drive spike 210 and below which recess 235 the head extends about 1/8 inch. The shank 220 extending from below the head 222 to the second end 226 of the drive spike 210 extends longitudinally about 6½ inches total. Preferably, the cylindrical section 240 extends longitudinally about 1⅛ inches, the portion 244 extends about 7/8 inch, the at least one helical flute 248 extends about 3¾ inches and the end portion 266 extends about ¾ inch. The diameter of the end portion 266 is about ¾ inch and the diameter of the cylindrical section 240, the portion 244 and the at least one helical flute 248 are all about 5/16 inch.

Preferably, the fastener of the present invention comprises a metal, more preferably iron or steel, most preferably carbon steel, for example C1045. Any material suitable for forming and having sufficient strength for the fastener of the present invention may be used as will be understood by one of skill in the art.

Although the invention herein has been described in connection with a preferred embodiment thereof, it will be appreciated by those skilled in the art that additions, modifications, substitutions, and deletions not specifically described may be made without departing from the spirit and scope of the invention as defined in the appended claims. It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.

Claims

1. A fastener comprising: an elongated shank extending along a longitudinal axis, a first end and a second end; a head formed at said first end of said shank, said head extending radially outwardly from said longitudinal axis; at least one helical thread portion extending along at least a portion of said shank; and a substrate gripping portion extending along at least a portion of said shank between said head and said at least one helical thread portion, said substrate gripping portion comprising at least one gripping member extending radially outwardly from said longitudinal axis.

2. The fastener of claim 1, wherein said at least one helical thread portion is different from said substrate gripping portion.

3. The fastener of claim 1, wherein said at least one gripping member comprises a plurality of gripping members.

4. The fastener of claim 1, wherein said at least one gripping member comprises at least one elongated protrusion extending substantially parallel to said longitudinal axis.

5. The fastener of claim 4, wherein said at least one protrusion is generally rectangularly shaped.

6. The fastener of claim 5 wherein said at least one protrusion comprises a plurality of rectangularly shaped protrusions distributed around a circumference of said shank.

7. The fastener of claim 1 wherein said at least one gripping member comprises an annular ring extending around said shank.

8. The fastener of claim 1, wherein said head comprises a polygonally shaped outer surface.

9. The fastener of claim 1, further comprising a flange extending radially outwardly from said longitudinal axis.

10. The fastener of claim 1, further comprising a protrusion extending axially from said head.

11. The fastener of claim 1, wherein said fastener comprises metal.

12. The fastener of claim 1, wherein said second end is blunt.

13. The fastener of claim 1 further comprising a smooth cylindrical section extending between said head and said substrate gripping portion.

14. The fastener of claim 1 wherein said helical thread portion further comprises at least four flutes.

15. A fastener comprising: an elongated shank having a longitudinal axis; a head formed at a first end of said shank, said head comprising a polygonally shaped outer surface; a substrate gripping portion extending along at least a portion of said shank between said head and a second end of said shank, said substrate gripping portion comprising at least one gripping member extending radially outwardly from said longitudinal axis, said at least one gripping member being polygonally shaped.

16. The fastener of claim 15 further comprising a helical threaded portion extending axially from said gripping portion toward said second end.

17. The fastener of claim 15 wherein said at least one gripping member comprises a plurality of gripping members.

18. The fastener of claim 17 wherein said at least one gripping member further comprises a plurality of protrusions extending from said shank.

19. A fastener comprising: an elongated shank having a head portion formed at a first end of said shank, said head portion adapted to be gripped by a tool; a plurality of protrusions extending radially outwardly from said shank, said plurality of protrusions extending between said head portion and a second end of said shank; and a helical thread portion extending axially along at least a portion of said shank, extending between said plurality of protrusions and said second end.

20. The fastener of claim 19 wherein said plurality of protrusions extend along a longitudinal axis between said head portion and said second end of said shank.