Fastener for stucco or hard board substrates

• US 20090269164A1
• Filed: 04/28/2008
• Published: 10/29/2009
• Est. Priority Date: 04/28/2008
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Broomfield, Donald J., Gonciarz, Mark Edward, Latz, Mark D.
• Granted Patent: US 8,511,957 B2
• Time in Patent Office: Days
• US Class Current: 411/416
• CPC Class Codes: F16B 25/0026 the material being a hard non-organic material, e.g. stone, concrete or drywall F16B25/0031 takes precedence
• CPC Class Codes: F16B 25/0068 with multiple-threads, e.g. a double thread screws
• CPC Class Codes: F16B 25/0078 with a shaft of non-circular cross-section or other special geometric features of the shaft

Abstract

A self-tapping fastener, which has been especially constructed for use in connection with the insertion and installation thereof into stucco, gypsum, wallboard, or other hard board substrates, wherein the forward end portion of the shank portion of the self-tapping fastener is provided with a pair of diametrically opposed flat sections which effectively form at least one pair of diametrically opposed tapping threads so as to effectively perform the thread tapping process despite exhibiting some abrasion of the forwardmost threads. In addition, the flat sections also effectively define recessed pockets for accommodating any dust, particles, debris, or the like, which will be generated during the thread tapping process.

Claims

1. A self-tapping fastener for forming threads within a substrate, comprising:

a head portion;

an axially oppositely disposed forward end tip portion;

a shank portion extending from said head portion to said forward end tip portion;

thread means defined upon said shank portion for self-tapping female threads within a substrate; and

at least one flat formed upon an external surface portion of said shank portion of said self-tapping fastener for defining at least one self-tapping thread upon said shank portion of said self-tapping fastener, from said thread means defined upon said shank portion and within the vicinity of said forward end tip portion, so as to form female threads within the substrate.

2. The self-tapping fastener as set forth in claim 1, wherein:

said at least one flat, formed upon said external surface portion of said shank portion of said self-tapping fastener, effectively interrupts the circumferential continuity of said thread means so as to effectively define said at least one self-tapping thread disposed upon said shank portion of said self-tapping fastener.

3. The self-tapping fastener as set forth in claim 2, wherein:

said thread means has a predetermined thread pitch as defined between successive threads of said thread means; and

said at least one flat has a predetermined axial length dimension such that the circumferential continuity of at least two successive threads of said thread means are effectively interrupted by said at least one flat so as to effectively define a pair of axially spaced self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

4. The self-tapping fastener as set forth in claim 1, wherein:

said at least one flat formed upon said external surface portion of said shank portion of said self-tapping fastener also defines a recessed pocket for physically accommodating any dust particles generated during the self-tapping of said self-tapping fastener into the substrate such that the dust particles do not interfere with and retard the self-tapping process of said self-tapping fastener.

5. The self-tapping fastener as set forth in claim 1, wherein:

said thread means comprises a dual thread lead comprising a first primary thread lead and a second secondary thread lead wherein the crest-to-crest diametrical extent of said first primary thread lead is greater than the crest-to-crest diametrical extent of said second secondary thread lead.

6. The self-tapping fastener as set forth in claim 5, wherein:

successive threads of said first primary thread lead are interposed between successive threads of said second secondary thread lead, and successive threads of said second secondary thread lead are interposed between successive threads of said first primary thread lead.

7. The self-tapping fastener as set forth in claim 1, wherein:

said at least one flat formed upon said external surface portion of said shank portion of said self-tapping fastener comprises a pair of diametrically opposed flats formed upon diametrically opposed external side surface portions of said shank portion of said self-tapping fastener for defining at least one pair of diametrically opposed self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

8. The self-tapping fastener as set forth in claim 7, wherein:

said pair of diametrically opposed flats, formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener, effectively interrupt the circumferential continuity of said thread means so as to effectively define said at least one pair of diametrically opposed self-tapping threads disposed upon said shank portion of said self-tapping fastener.

9. The self-tapping fastener as set forth in claim 8, wherein:

said thread means has a predetermined thread pitch as defined between successive threads of said thread means; and

said pair of diametrically opposed flats have predetermined axial length dimensions such that said circumferential continuity of at least two successive threads of said thread means are effectively interrupted by said pair of diametrically opposed flats so as to effectively define two pairs of axially spaced and diametrically opposed self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

10. The self-tapping fastener as set forth in claim 7, wherein:

said pair of diametrically opposed flats formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener also define a pair of diametrically opposed recessed pockets for physically accommodating any dust particles generated during the self-tapping of said self-tapping fastener into the substrate such that the dust particles do not interfere with and retard the self-tapping process of said self-tapping fastener.

11. The self-tapping fastener as set forth in claim 10, wherein:

said thread means has a predetermined crest-to-crest diametrical extent; and

the diametrical spacing between said pair of diametrically opposed flats, formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener, is within the range of 35-65% of said predetermined crest-to-crest diametrical extent of said thread means.

12. A self-tapping fastener for forming threads within a substrate, comprising:

a head portion;

an axially oppositely disposed forward end tip portion;

a shank portion extending from said head portion to said forward end tip portion;

thread means defined upon said shank portion for self-tapping female threads within a substrate; and

at least one flat formed upon an external surface portion of said shank portion of said self-tapping fastener for defining at least one recessed pocket for physically accommodating any dust particles generated during the self-tapping of said self-tapping fastener into the substrate such that the dust particles do not interfere with and retard the self-tapping process of said self-tapping fastener.

13. The self-tapping fastener as set forth in claim 12, wherein:

said at least one flat, formed upon said external surface portion of said shank portion of said self-tapping fastener, effectively interrupts the circumferential continuity of said thread means so as to also effectively define at least one self-tapping thread disposed upon said shank portion of said self-tapping fastener.

14. The self-tapping fastener as set forth in claim 13, wherein:

said thread means has a predetermined thread pitch as defined between successive threads of said thread means; and

said at least one flat extends rearwardly for a predetermined axial length from said forward end tip portion toward said head portion such that the circumferential continuity of at least two successive threads of said thread means are effectively interrupted by said at least one flat so as to effectively define a pair of axially spaced self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

15. The self-tapping fastener as set forth in claim 12, wherein:

said at least one flat formed upon said external surface portion of said shank portion of said self-tapping fastener comprises a pair of diametrically opposed flats formed upon diametrically opposed external side surface portions of said shank portion of said self-tapping fastener for defining a pair of diametrically opposed recessed pockets upon said shank portion of said self-tapping fastener for physically accommodating any dust particles generated during the self-tapping of said self-tapping fastener into the substrate such that the dust particles do not interfere with and retard the self-tapping process of said self-tapping fastener.

16. The self-tapping fastener as set forth in claim 15, wherein:

said pair of diametrically opposed flats, formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener, effectively interrupts the circumferential continuity of said thread means so as to effectively define a pair of diametrically opposed self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

17. The self-tapping fastener as set forth in claim 15, wherein:

said thread means has a predetermined thread pitch as defined between successive threads of said thread means; and

said pair of diametrically opposed flats formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener extend rearwardly for a predetermined axial length from said forward end tip portion toward said head portion such that the circumferential continuity of at least two successive threads of said thread means are effectively interrupted by said pair of flats so as to effectively define two pairs of axially spaced and diametrically opposed self-tapping threads upon said shank portion of said self-tapping fastener so as to form the female threads within the substrate.

18. The self-tapping fastener as set forth in claim 15, wherein:

said thread means has a predetermined crest-to-crest diametrical extent; and

the diametrical spacing between said pair of diametrically opposed flats, formed upon said diametrically opposed external side surface portions of said shank portion of said self-tapping fastener, is within the range of 35-65% of said predetermined crest-to-crest diametrical extent of said thread means.

19. The self-tapping fastener as set forth in claim 12, wherein:

said thread means comprises a dual thread lead comprising a first primary thread lead and a second secondary thread lead wherein the crest-to-crest diametrical extent of said first primary thread lead is greater than the crest-to-crest diametrical extent of said second secondary thread lead.

20. The self-tapping fastener as set forth in claim 19, wherein:

successive threads of said first primary thread lead are interposed between successive threads of said second secondary thread lead, and successive threads of said second secondary thread lead are interposed between successive threads of said first primary thread lead.