Weldless building structures

Patent metadata

Field	Value
Publication number	US-10371192-B2
Application number	US-201715722509-A
Country	US
Kind code	B2
Filing date	Oct 2, 2017
Priority date	Feb 19, 2010
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

Abstract

A building structure including a first building member and a second building member may be connected by a plurality of fasteners, each fastener having a head, a threaded portion having a through hardness of between HRB 70 and HRC 40, a thread-forming portion of at least HRC 50 hardness enabling the fastener to form threads in at least the second steel building member, and a fluted lead portion of at least HRC 50 hardness with a nominal diameter between 70 and 95% of major diameter, such that the fastener is capable of providing a ratio of strip torque to thread-forming torque of at least 3.0 and a ratio of strip torque to drive torque greater than 6.0 when the second steel building member having a thickness of 0.25 inch and the fluted lead portion having at least one diameter within nominal diameter between 80 and 98% of major diameter.

First claim

What is claimed is:

1. A fastener comprising:
a head,
a threaded portion adjacent the head,
a thread-forming portion of at least HRC 50 hardness adjacent the threaded portion, and
a fluted lead portion of at least HRC 50 hardness adjacent the thread-forming portion with a nominal diameter in a range from 60% to 95% of major diameter of the threaded portion adapted to form a fastener opening,
the thread-forming portion having a series of lobes with recesses between said lobes and said lobes positioned about the rotational axis where each lobe having a lead portion and a tailing portion, the lead portion and first adjacent recess is at a first angle in a range from 50° to 100° from a plane tangent to the lobe adjacent the leading portion, and the tailing portion and second adjacent recess is at a second angle in a range from 25° to 50° from a plane tangent to the lobe adjacent the tailing portion, where the first angle is greater than the second angle.

2. The fastener of claim 1 where the head is capable of clamping a first steel building member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to thread-forming torque of at least 3.0 and a ratio of strip torque to drive torque greater than 8.0 over a range of combined thickness of the first and the second steel building members from about 0.036 inch to 0.084 inch.

3. The fastener of claim 1 where the head is capable of clamping a first steel building member to a second steel building member with the fastener installed and the thread forming portion having a ratio of strip torque to thread-forming torque of at least 3.0 and a ratio of strip torque to drive torque greater than 6.0 over a range of combined thickness of the first and the second steel building members from about 0.036 inch to 0.108 inch.

4. The fastener of claim 1 , where the threaded portion adjacent the head has a through hardness in a range from HRB 70 and HRC 40.

5. The fastener claimed in claim 4 , where the fasteners have up to five threads between the threaded portion and the thread-forming portion hardened to at least HRC 50 hardness.

6. The fastener claimed in claim 1 , where the fasteners are nutable.

7. The fastener claimed in claim 1 , where the head is capable of clamping a first steel building member to a second steel building member with the fastener installed and the thread forming portion and a combined thickness of the first steel building member and the second steel building member at the fastener is no more than 0.125 inch in thickness.

8. The fastener claimed in claim 1 , where the fluted lead portion has a nominal diameter in a range from 62% to 85% of major diameter.

9. The fastener claimed in claim 1 , where the thread-forming portion has a shape selected from a group consisting of quadlobular and pentalobular.

10. The fastener claimed in claim 1 , where the lead portion of the fluted lead portion has a milled point.

11. The fastener claimed in claim 1 , where the fluted lead portion has at least HRC 50 induction hardness.

12. The fastener claimed in claim 1 , where the threaded portion has less than 60° thread angle and back-tapered threads.

13. The fastener claimed in claim 1 , where the threaded portion has from 45 to 50° thread angle and back-tapered threads.

14. The fastener claimed in claim 1 , where the thread-forming portion is from 3 to 7 thread pitch in length.

15. The fastener claimed in claim 1 , the threaded portion comprising a major diameter extending to within 1.5 of the thread pitch of the head.

16. The fastener claimed in claim 15 , where the head of the fasteners are undercut and adapted to deform the first steel building member on tightening of the fasteners.

17. The fastener claimed in claim 1 , where a sealing member is positioned between the head and the threaded portion.

18. The fastener claimed in claim 1 , where serrations are provided in the underside of the head.

19. The fastener claimed in claim 1 where the head is capable of clamping a first steel member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to tread-forming torque of at least 3.0 and a ratio of strip torque to drive torque is greater than 6.0 over a range of combined thickness of first and second steel building members from about 0.036 inch to 0.084 inch.

20. The fastener claimed in claim 1 where the head is capable of clamping a first steel member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to tread-forming torque of at least 4.0 and a ratio of strip torque to drive torque is greater than 8.0 over a range of combined thickness of first and second steel building members from about 0.036 inch to 0.084 inch.

21. The fastener claimed in claim 1 where the head is capable of clamping a first steel member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to tread-forming torque of at least 4.0 and a ratio of strip torque to drive torque is greater than 10.0 over a range of combined thickness of first and second steel building members from about 0.036 inch to 0.084 inch.

22. The fastener claimed in claim 1 where the head is capable of clamping a first steel member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to tread-forming torque of at least 3.5 and a ratio of strip torque to drive torque is greater than 6.0 over a range of combined thickness of first and second steel building members from about 0.036 inch to 0.084 inch.

23. The fastener claimed in claim 1 where the head is capable of clamping a first steel member to a second steel building member with the fastener installed and the series of lobes are structured having a ratio of strip torque to tread-forming torque of at least 3.0 and a ratio of strip torque to drive torque is greater than 4.0 over a range of combined thickness of first and second steel building members from about 0.036 inch to 0.108 inch.

Assignees

• Nucor Corp
• Asia Fastening Us Inc

Inventors

• Dayton Lionel E
• Lukes Richard W

Classifications

• F16B25/0021

  the material being metal, e.g. sheet-metal or aluminium (F16B25/0031 takes precedence) · CPC title

• F16B25/0063

  with a non-threaded portion on the shaft of the screw · CPC title

• E04B2001/2454

  Connections between open and closed section profiles · CPC title

• F16B25/10

  Screws performing an additional function to thread-forming, e.g. drill screws {or self-piercing screws} · CPC title

• E04B2001/2418

  Details of bolting · CPC title