Drywall fastener

Abstract

A drive-in expansion fastener is provided having a generally cylindrical, hollow body with a tapered end formed from an angular truncation of the body. The body is reinforced by at least one longitudinal rib so as to permit drive-in penetration from the tapered end even if the fastener is formed from plastic materials. The fastener is retained within the wall by at least one pair of hinged flanges which expand .Iadd.or move .Iaddend.circumferentially .Iadd.apart .Iaddend.in response to the threaded insertion of an ordinary screw within the hollow portion of the body. That screw engages an inclined surface within the body to cam the flanges outwardly. The flanges engage the back surface of the wall while a longitudinally .[.slit portion.]. .Iadd.split length .Iaddend.of the body expands within the hole created by drive-in penetration.

What is claimed is: 
     
       1. An expansion fastener .Iadd.capable of being directly hammered, punched or screwed into a drywall board .Iaddend.for securing a retaining member, comprising: a generally cylindrical, longitudinally extending .Iadd.hollow .Iaddend.body portion .Iadd.having a tip at one end for penetrating the drywall board and a base portion at the other end with a passageway extending therethrough between said tip end and base portion.Iaddend.;   said body portion including a .Iadd.longitudinally extending .Iaddend.tapered portion .[.at one end thereof.]. .Iadd.extending from the tip end towards the base portion for effecting a clean and gradual cut through the drywall board.Iaddend.;   said body portion including a flange portion .[.which expands circumferentially.]. .Iadd.extending in the longitudinal direction of the body portion, said flange portion expands radially outwardly .Iaddend.in response to insertion of said retaining member into said body portion .Iadd.and at least a portion of said flange portion is displaced circumferentially.Iaddend.; .[.and.].   .Iadd.said flange portion includes means facing toward said tip end for cutting through the drywall board as the fastener is inserted; and .Iaddend.   prior to said expansion of said flange portion, said flange portion projects radially outward from said body portion.   
     
     
       2. The fastener according to claim 1 wherein said tapered portion is formed by an angular truncation .[.of one end.]. of said body portion .Iadd.extending longitudinally from said tip end toward said base portion.Iaddend.. 
     
     
       3. The fastener according to claim 1 wherein said tapered portion includes a cavity for receiving debris caused by insertion of said fastener into .[.a.]. .Iadd.said drywall .Iaddend.board .[.member.].. 
     
     
       4. The fastener according to claim 3 wherein .[.said body portion includes a generally longitudinal passageway therethrough and.]. said cavity includes a portion of said passageway. 
     
     
       5. The fastener according to claim 4 wherein said passageway includes a longitudinal restriction having an inclined face for initial engagement with said retaining member. .[.6. The fastener according to claim 1 wherein said flange portion extends longitudinally with said body 
     
     
        portion..].7. The fastener according to claim 1 wherein said body portion includes an exterior surface, and further including a tapered longitudinal rib for reinforcing said body portion, said rib being disposed adjacent 
     
     
        said exterior surface and radially extending from said body portion. 8. The fastener according to claim 1 wherein said body portion includes an exterior surface, and further including means connected to said exterior 
     
     
        surface for preventing rotation of said body portion. 9. An expansion fastener .Iadd.capable of being directly hammered, punched or screwed into a drywall board .Iaddend.for securing a retention member to .[.a.]. .Iadd.said .Iaddend.board, comprising: a generally cylindrical, longitudinally extending .Iadd.hollow .Iaddend.body portion having .Iadd.a tip end at one end for penetrating the drywall board and a base portion at the other end and .Iaddend.a substantially longitudinal passageway therethrough;   said body portion including a tapered means .Iadd.extending from the tip end towards the base portion .Iaddend.for facilitating penetration of said board by said body portion;   said tapered means being formed by an angular truncation of .[.one end of.]. said body portion .Iadd.extending from said tip end towards said base portion.Iaddend.;   said body portion including a retaining portion for preventing removal of said body portion from said board;   said retaining portion including a flange .[.member.]. .Iadd.portion .Iaddend.radially projecting .Iadd.outwardly .Iaddend.from said body portion and extending longitudinally therewith; .[.and.]. said .[.retaining.]. .Iadd.flange .Iaddend.portion expands .[.circumferentially.]. .Iadd.radially .Iaddend.in response to insertion of said retention member into said passageway .Iadd.and moves circumferentially; and   said flange portion includes means facing towards said tip end for cutting   
     
     
        through the drywall board as the fastener is inserted.Iaddend.. 10. The fastener according to claim 9 wherein said angular truncation exposes a portion of said passageway to receive board debris caused by said 
     
     
        penetration of said board by said body portion. 11. The fastener according to claim 9 wherein said .[.retaining.]. .Iadd.flange .Iaddend.portion expands .Iadd.radially and moves .Iaddend.circumferentially adjacent and exterior of said board in said response to insertion of said retention 
     
     
        member into said passageway. 12. The fastener according to claim 9 wherein said tapered means includes internal and external surfaces and board-cutting edges at said internal surface to facilitate said 
     
     
        penetration of said board. 13. The fastener according to claim 9 wherein the angle of said truncation with respect to said body portion is established for a particular board composition such that drive-in penetration of said board by said body portion does not result in 
     
     
        formation of a blow out region on said board. 14. The fastener according to claim 9 wherein the angle of said truncation with respect to the 
     
     
        longitudinal axis of said body portion is less than 45 degrees. 15. The fastener according to claim 9 wherein .[.said board comprises drywall material and.]. the angle of said truncation with respect to the 
     
     
        longitudinal axis of said body portion is less than 10 degrees. 16. The fastener according to claim 9 wherein said .[.body.]. .Iadd.base .Iaddend.portion includes a base shoulder opposite said tapered means, said shoulder including second flange means for preventing rotation of 
     
     
        said body portion. 17. The fastener according to claim 16 wherein said second flange means includes a plurality of radially projecting elements which extend longitudinally along said body portion from said shoulder. 
     
     
            The fastener according to claim 9 further including expansion means disposed within said passageway for moving said .[.retaining.]. .Iadd.flange .Iaddend.portion in response to said insertion of said 
     
     
        retention member into said passageway. 19. The fastener according to claim 18 wherein said expansion means is formed as a longitudinal restriction in said passageway having a ramped end for engaging said retention member. 
     
     
            The fastener according to claim 19 wherein said expansion means includes longitudinal slot means for defining .[.the.]. .Iadd.a 
     
     
        .Iaddend.base of said .[.retaining.]. .Iadd.flange .Iaddend.portion. 21. The fastener according to claim 20 wherein said .Iadd.means of said .Iaddend.flange .[.member.]. .Iadd.portion .Iaddend.includes a forward cutting edge having an angle of inclination at least as steep as the angle of said truncation with respect to the longitudinal axis of said body 
     
     
        portion. 22. The fastener according to claim 9 wherein said flange .[.member.]. .Iadd.portion .Iaddend.includes at least one pair of initially adjacent, parallel .[.projection.]. .Iadd.body and flange .Iaddend.elements .Iadd.before being expanded .Iaddend.which move .Iadd.radially outwardly and .Iaddend.circumferentially apart in response 
     
     
        to said insertion of said retention member into said passageway. 23. The fastener according to claim 22 wherein said flange .[.member.]. .Iadd.portion .Iaddend.includes a plurality of pairs of .[.projection.]. .Iadd.said body and flange .Iaddend.elements spaced apart longitudinally 
     
     
        along said body portion. 24. The fastener according to claim 23 wherein said plurality of pairs of .[.projection.]. .Iadd.body and flange .Iaddend.elements are sequentially moved apart by said insertion of said 
     
     
        retention member into said passageway. 25. The fastener according to claim 24 wherein said body portion includes a longitudinal split, said split being aligned between said pairs of .[.projection.]. .Iadd.body and flange .Iaddend.elements .[.and providing means for said body portion to expand circumferentially in response to said insertion of said retention member into said passageway.]. .Iadd.wherein as said body portion expands radially said body and flange elements of at least one of said pairs of 
     
     
        body and flange elements move circumferentially apart.Iaddend.. 26. The fastener according to claim 9 wherein said body portion is formed from a 
     
     
        moldable, plastic material. 27. A drive-in expansion fastener .Iadd.capable of being directly hammered, punched or screwed into a drywall or plaster board .Iaddend.for securing a retention element to .[.a.]. .Iadd.said .Iaddend.drywall or plaster board, comprising: a generally cylindrical, longitudinally extending .Iadd.hollow .Iaddend.body portion having .Iadd.a tip end at one end for penetrating the drywall or plaster board and a base portion at the other end with .Iaddend.a longitudinal passageway .Iadd.extending .Iaddend.therethrough .Iadd.between said tip end and said base portion.Iaddend.;   said body portion including a tapered means .Iadd.extending longitudinally and .Iaddend.having board-cutting edges for facilitating drive-in penetration of said board by said body portion;   said tapered means being formed as an angular truncation of .[.one.]. .Iadd.said tip .Iaddend.end of said body portion;   the angle of said truncation with respect to said body portion being established such that penetration of said board by said body portion does not result in formation of a blow out region on said board;   .[.a base portion formed on said body portion at an end opposite said tapered means;.].   said base portion including a radially .Iadd.outwardly .Iaddend.extending shoulder;   said body portion including a retaining means longitudinally spaced apart from said shoulder for preventing removal of said body portion from said board;   said retaining means including a flange portion radially projecting .Iadd.outwardly .Iaddend.from said body portion; .[.and.].   .Iadd.said flange portion includes means facing toward said tip end for cutting through the board as the fastener is inserted, and .Iaddend.   an expansion means disposed within said passageway for .[.circumferentially.]. .Iadd.radially .Iaddend.expanding said flange portion outwardly with respect to said body portion in response to insertion of said retention element into said passageway .Iadd.and for   
     
     
        circumferentially displacing said flange portion.Iaddend.. 28. The fastener according to claim 27 wherein said fastener is molded from a 
     
     
        nylon material. 29. The fastener according to claim 27 wherein said retention element is threaded for rotatable insertion into said passageway 
     
     
        and said passageway is formed from a self-lubricating material. 30. The fastener according to claim 27 wherein said passageway is longitudinally exposed by said angular truncation such that board material is received therein during said drive-in penetration of said board by said body 
     
     
        portion. 31. The fastener according to claim 30 wherein said .[.retaining means.]. .Iadd.flange portion .Iaddend.includes a plurality of pairs of spaced apart hinged members, at least one of said pairs .[.including said flanged portion.]. .Iadd.being circumferentially displaceable apart as 
     
     
        said flange portion is radially expanded.Iaddend.. 32. A drive-in expansion fastener .Iadd.capable of being directly hammered, punched or screwed into a drywall or plaster board .Iaddend.for securing a retention element to .[.a.]. .Iadd.said .Iaddend.drywall or plaster board, comprising: a generally cylindrical, longitudinally extending .Iadd.hollow .Iaddend.body portion having .Iadd.a tip end at one end for penetrating the drywall or plaster board and a base portion at the other end and with .Iaddend.a longitudinal passageway .Iadd.extending .Iaddend.therethrough;   said body portion including a .Iadd.longitudinally extending .Iaddend.tapered means having board-cutting edges for facilitating drive-in penetration of said board by said body portion;   said tapered means being formed as an angular truncation of .[.one.]. .Iadd.said tip .Iaddend.end of said body portion;   the angle of said truncation with respect to said body portion being established such that penetration of said board by said body portion does not result in formation of a blow out region on said board;   said passageway is longitudinally exposed by said angular truncation such that board material is received therein during said drive-in penetration of said board by said body portion;   .[.a base portion formed on said body portion at an end opposite said tapered means;.].   said base portion including a radially .Iadd.outwardly .Iaddend.extending shoulder;   said body portion including a retaining means longitudinally spaced apart from said shoulder for preventing removal of said body portion from said board;   said retaining means includes a plurality of pairs of spaced apart hinged members, at least one of said pairs including a flange portion radially projecting from said body portion;   the hinge base of said hinged members is formed by .Iadd.a .Iaddend.longitudinal .[.slits.]. .Iadd.split length .Iaddend.in said body portion; and   an expansion means disposed within said passageway for moving said flange portion .Iadd.circumferentially and radially .Iaddend.outwardly with respect to the circumference of said body portion in response to insertion   
     
     
        of said retention element into said passageway. 33. The fastener according to claim 32 wherein said .[.body.]. .Iadd.base .Iaddend.portion includes a circumferential base shoulder for receiving the impact of means for 
     
     
        causing said drive-in penetration of said board by said body portion. 34. The fastener according to claim 33 wherein said shoulder includes visible indicia thereon for indicating the orientation of said fastener 
     
     
        within said board. 35. The fastener according to claim 33 wherein said shoulder includes longitudinally extending projections for preventing rotation of said body portion with respect to said board after said 
     
     
        drive-in penetration and during insertion of said retention element. 36. An expansion fastener .Iadd.capable of being directly hammered, punched or screwed into a drywall board .Iaddend.for securing a retaining member .Iadd.thereto.Iaddend., comprising: a generally cylindrical, longitudinally extending .Iadd.hollow .Iaddend.body portion .Iadd.having a tip end at one end for penetrating the drywall board and a base portion at the other end with a passageway extending therethrough between said tip and and base portion.Iaddend.;   said body portion including a .Iadd.longitudinally extending .Iaddend.tapered portion .[.at one end thereof.]. .Iadd.extending from the tip end towards the base portion for effecting a clean and gradual cut through the drywall board.Iaddend.;   said body portion including a flange portion which expands .Iadd.radially and is displaced .Iaddend.circumferentially in response to insertion of said retaining member into said body portion;   said tapered portion includes a cavity for receiving debris caused by insertion of said fastener into .[.a.]. .Iadd.said drywall .Iaddend.board .[.member.].;   .[.said body portion includes a generally longitudinal passageway therethrough;.].   said cavity includes a portion of said passageway; and   said passageway includes a longitudinal restriction having an inclined face for initial engagement with said retaining member.Iadd.;   said flange portion includes means facing towards said tip end for cutting through the drywall board as the fastener is inserted; and   prior to said expansion of said flange portion, said flange portion   
     
     
        projects radially outwardly from said body portion.Iaddend.. 37. The fastener according to claim 36 wherein said tapered portion is formed by 
     
     
        an angular truncation of one end of said body portion. 38. The fastener according to claim 36 wherein said body portion includes an exterior surface, and further including a tapered longitudinal rib for reinforcing said body portion, said rib being disposed adjacent said exterior surface and radially extending .Iadd.outwardly .Iaddend.from said body portion. 
     
     
            The fastener according to claim 36 wherein said body portion includes an exterior surface, and further including means connected to said exterior surface .Iadd.adjacent said base portion .Iaddend.for preventing rotation of said body portion.