Fastener for cementitious materials

• US 8,556,558 B1
• Filed: 07/31/2006
• Issued: 10/15/2013
• Est. Priority Date: 07/31/2006
• Status: Expired due to Fees

• Current Assignee: Hunt, Christopher M.
• Original Assignee: Hunt, Christopher M.
• Inventors: Hunt, Christopher M.
• Primary Examiner(s): DELISLE, ROBERTA S
• Application Number:
  US11/497,653
• Time in Patent Office: 2,633 Days
• Field of Search: 411/82, 411/82.1, 411/258, 411/386, 411/387.1, 411/387.8, 411/395, 411/512, 411/930
• US Class Current: 411/82.1
• CPC Class Codes: F16B 13/002 self-cutting
• CPC Class Codes: F16B 13/141 Fixing plugs in holes by the use of settable material
• CPC Class Codes: F16B 25/00 Screws that cut thread in the body into which they are screwed, e.g. wood screws F16B35/065 takes precedence; joining sheets or plates using screws with two separate threads F16B5/0275, using screws with adjustment sleeves F16B5/0283
• CPC Class Codes: F16B 39/021 by injecting a settable material after the screwing down

Abstract

An apparatus and method for fastening cementitious components together or for fastening a cementitious component to a non-cementitious component to form a structure. In a preferred embodiment, the apparatus is a screw having a hollow shaft from which threads protrude and a tip comprising a plurality of drilling teeth or a plurality of thread members that surround said central space, each of said thread members forming a two-dimensional spiral. In use, the invention is operated by screwing it into the cementitious components and then injecting an adhesive into the void created by the screwing step.

Claims

1. A fastener for use in a cementitious material, said fastener comprising:

a shaft comprising a first portion having a first shaft outer surface, a first shaft inner surface and a first shaft outside diameter and a second portion having a second shaft outer surface, a second shaft inner surface and a second shaft outside diameter, said shaft having a longitudinal void therein, a longitudinal axis and two ends;

a shaft thread that is attached to said first shaft outer surface and said second shaft outer surface, said shaft thread having a variable shaft thread outer diameter with a maximum extent;

a tip that is attached to one end of said shaft, said tip having an upper tip outside diameter that is greater than said second shaft outside diameter, said tip comprising tip threads that are self-centering and self-setting, said tip threads comprising a plurality of thread members that are substantially triangular in cross section and that surround a substantially conical space that is in communication with said longitudinal void; and

a head that is attached to the other end of said shaft.

2. The fastener of claim 1 wherein said second shaft inner surface is rifled.

3. The fastener of claim 1 wherein said head comprises grinding teeth and has a head outer diameter that is less than or equal to the maximum extent of said shaft thread outer diameter.

4. The fastener of claim 1 wherein said shaft thread has holes therein that are aligned parallel with said longitudinal axis.

5. The fastener of claim 1 wherein said second shaft inner surface is provided with a plurality of spiraling ridges that extend from said second end to said first shaft inner surface.

6. The fastener of claim 1 wherein said first portion has radial holes therein.

7. The fastener of claim 1 wherein said second portion has radial holes therein.

8. The fastener of claim 1 wherein said head has a receiver for a bit, said receiver being in communication with said longitudinal void, said receiver having slots therein.

9. A fastener for use in a cementitious material, said fastener comprising:

a shaft comprising a first portion having a first shaft outer surface and a first shaft inner surface and a second portion having a second shaft outer surface and a second shaft inner surface, said shaft having a longitudinal void therein and two ends;

a shaft thread that is attached to said first shaft outer surface and said second shaft outer surface;

a tip that is attached to one end of said shaft, said tip comprising tip threads, said tip threads comprising a plurality of thread members that surround a space that is in communication with said longitudinal void; and

a head that is attached to the other end of said shaft.

10. A fastener comprising:

a shaft having two ends, an outer surface and a longitudinal bore;

a screw thread having a base that is attached to said outer surface along a curve traced on said outer surface by its rotation past a point crossing a right section of said shaft at an oblique angle; and

a tip that is attached to one end of said shaft, said tip having a central space that is in communication with said longitudinal bore, said tip comprising a plurality of thread members that surround said central space, each of said thread members forming a two-dimensional spiral having a maximum outer diameter.

11. The fastener of claim 10 further comprising a head that is attached to the other end of said shaft.

12. The fastener of claim 11 wherein said head has a receiver that is capable of accepting a screwdriver or drill bit of polygonal cross section.

13. The fastener of claim 10 wherein said screw thread is perforated by a plurality of aligned holes.

14. The fastener of claim 10 wherein said shaft comprises a first portion and a second portion, said first portion being cylindrical in shape and having a cylinder diameter and said second portion having the shape of a truncated cone with a base having a base diameter, and wherein said base diameter is greater than said cylinder diameter and approximately equal to said maximum outer diameter.

15. The fastener of claim 10 wherein said longitudinal bore is rifled.

16. The fastener of claim 10 wherein a plurality of holes extend from said longitudinal bore to said outer surface.

17. The fastener of claim 10 wherein said head has a hole through which an adhesive is injectable.

18. A fastener comprising:

a shaft having two ends, an outer surface and a longitudinal bore; and

wherein said shaft comprises a first portion and a second portion, said first portion being cylindrical in shape and having a cylinder diameter and said second portion having the shape of a truncated cone with a base having a base diameter, and wherein said base diameter is greater than said cylinder diameter and approximately equal to said maximum outer diameter;

a screw thread having a base that is attached to said outer surface along a curve traced on said outer surface by its rotation past a point crossing a right section of said shaft at an oblique angle;

a tip that is attached to one end of said shaft, said tip having a central space that is in communication with said longitudinal bore, said tip having a plurality of drilling teeth protruding from it that surround said central space, said tip having a maximum outer diameter.

19. The fastener of claim 18 further comprising a head that is attached to the other end of said shaft.

20. The fastener of claim 19 wherein said head has a receiver that is capable of accepting a screwdriver or drill bit of polygonal cross section.

21. The fastener of claim 18 wherein said screw thread is perforated by a plurality of aligned holes.

22. The fastener of claim 18 wherein said longitudinal bore is rifled.

23. The fastener of claim 18 wherein a plurality of holes extend from said longitudinal bore to said outer surface.

24. The fastener of claim 18 wherein said head has a hole through which an adhesive is injectable.

25. A fastener for joining two separate cementitious items without pre-drilling of a hole into the two separate cementitious items in which to insert the fastener, said fastener comprising:

a shaft having two ends, an outer surface and a longitudinal bore;

a screw thread having a base that is attached to said outer surface along a curve traced on said outer surface by its rotation past a point crossing a right section of said shaft at an oblique angle; and

a tip that is attached to one end of said shaft, said tip having a central space that is in communication with said longitudinal bore, said tip comprising a plurality of thread members that surround said central space, each of said thread members forming a two-dimensional spiral having a maximum outer diameter;

wherein said tip, said screw thread and said tip constitute a single component and said fastener is operative to join the two separate cementitious items to produce an adhered and reinforced single object.