Helical coil fastener

Claim 2

A fastener for attaching insulation to a roof deck, said fastener comprising a retaining member having a top portion with an upper surface and a lower surface, an elongated hub integral with said top portion and extending downwardly from the lower surface of said top portion, said hub having a helical groove formed therein extending throughout a substantial portion of its length, the upper end of said helical groove having means to create a tensile load on said hub by a helical coil having at least the uppermost loop located in said helical groove on said hub, a helical coil having a plurality of loops, at least the uppermost loop of said helical coil located in said helical groove formed in said hub, the end portion of at least the uppermost loops of said helical coil contacting said means to create a tensile load on said hub to firmly mount said helical coil on said hub and the lower loops of said helical coil extending downwardly below the end of said hub, the lower end of the lowermost loop of said helical coil being formed with a point lying on the center line of said helical coil, said lower end being substantially parallel to the center line of said helical coil and self-tapping threads are formed along said lower end, whereby said helical coil is adapted to be screwed through insulation into a roof deck to hold insulation onto the roof deck and said self-tapping threads are adapted to penetrate the roof deck to attach said fastener to said roof deck.

Claim 3

A fastener as set forth in claim 1 wherein said helical groove formed in said hub has substantially the same pitch as said helical coil except for said means to create a tensile force on said hub.

Claim 4

A fastener as set forth in claim 1 wherein the lower end of the lowermost loop of said helical coil is formed with a point lying on the center line of said helical coil and is substantially parallel to the center line of said helical coil, whereby said pointed end is adapted to pass through a pilot hole in a light gauge sheet metal roof deck to attach said fastener to said roof deck.

Claim 5

A fastener as set forth in claim 1 wherein the lowermost loops of said helical coil are formed with a smaller diameter than the other loops in said helical coil and the lower end of the lowermost loop of said helical coil has a portion lying on the center line of said helical coil and parallel to the center line of said helical coil, whereby said lower end cooperates with a pilot hole formed in a light gauge metal roof deck to attach said fastener to said roof deck.

Claim 6

A fastener as set forth in claim 1 wherein said upper surface of said top portion of said plastic retaining member is formed with connecting means adapted to receive a fastener driving tool to drive said fastener.

Claim 7

A fastener as set forth in claim 5 including a recess formed in said top portion of said retaining member and said connecting means is a hexagonal hub located within said recess.

Claim 8

A fastener as set forth in claim 6 wherein said recess has a cylindrical transverse cross section.

Claim 9

A fastener as set forth in claim 6 wherein said recess has a hexagonal transverse cross section adapted to be driven by a fastener driving tool having a hexagonal exterior shape.

Claim 10

A fastener as set forth in claim 6 wherein said connecting means is a bore for receiving the driving tool.

Claim 11

A fastener as set forth in claim 1 wherein said hub has stop means formed therein at the upper end of said helical groove, whereby said stop means contacts the free end of the uppermost loop of said helical coil to prevent the end of said helical coil from contacting said lower surface of said top portion of said retaining member.

Claim 12

A fastener as set forth in claim 1 wherein said means to create a tensile force on said hub is a flat ramp formed on the upper surface of the upper end of said helical groove.

Claim 13

A fastener as set forth in claim 1 wherein said means to create a tensile force on said hub is the upper groove of said helical groove being formed perpendicular to the axis of said hub.

Claim 14

A fastener as set forth in claim 1 wherein said means to create a tensile force on said hub is at least the upper two threads of said helical groove having a smaller pitch than the remaining threads of said helical groove.

Claim 15

A fastener for attaching insulation to a roof deck, said fastener comprising a retaining member having a top portion with an upper surface and a lower surface, an elongated hub integral with said top portion and extending downwardly from the lower surface of said top portion, said hub having a helical groove formed therein extending throughout a substantial portion of its length, the upper end of said helical groove formed in said hub having means changing the lead between the upper end of said helical groove and at least the uppermost loop of a helical coil adapted to be mounted in said helical groove to create a tensile load on said hub by a helical coil having at least the uppermost loop located in said helical groove formed in said hub, stop means formed on said hub at the upper end of said helical groove, a helical coil having a plurality of loops, the uppermost loop of said helical coil having a free end and at least the uppermost loop of said helical coil being located in said helical groove formed in said hub and the end portion of at least the uppermost loop of said helical coil contacting said means to change the lead to create a tensile load on said hub to firmly mount said helical coil on said hub, said stop means on said hub contacting the free end of the uppermost loop of said helical coil to prevent the end of said helical coil from contacting said lower surface of said top portion of said retaining member and the lower loops of said helical coil extending downwardly below the end of said hub, whereby said helical coil is adapted to be screwed through insulation into a roof deck to hold insulation onto the roof deck.

Claim 16

A fastener for attaching insulation to a roof deck, said fastener comprising a retaining member having a top portion with an upper surface and a lower surface, an elongated hub integral with said top portion and extending downwardly from the lower surface of said top portion, said hub having a helical groove formed therein extending throughout a substantial portion of its length, the upper end of said helical groove formed in said hub having means changing the lead between the upper end of said helical groove and at least the uppermost loop of a helical coil adapted to be mounted in said helical groove to create a tensile load on said hub by a helical coil having at least the uppermost loop located in said helical groove formed in said hub, stop means formed on said hub at the upper end of said helical groove, a helical coil having a plurality of loops, the uppermost loop of said helical coil having a free end and at least the uppermost loop of said helical coil being located in said helical groove formed in said hub and the end portion of at least the uppermost loop of said helical coil contacting said means to change the lead to create a tensile load on said hub to firmly mount said helical coil on said hub, said stop means on said hub contacting the free end of the uppermost loop of said helical coil to prevent the end of said helical coil from contacting said lower surface of said top portion of said retaining member and the lower loops of said helical coil extending downwardly below the end of said hub, whereby said helical coil is adapted to be screwed through insulation into a roof deck to hold insulation onto the roof deck.

Claim 17

A fastener as set forth in claim 14 wherein said means changing the lead is a flat ramp formed on the upper surface of the upper end of said helical groove.

Claim 18

A fastener as set forth in claim 14 wherein said means changing the lead is the upper groove of said helical groove being formed perpendicular to the axis of said hub.

Claim 19

A fastener as set forth in claim 14 wherein said means changing the lead is at least the upper two threads of said helical groove having a smaller pitch than the remaining threads of said helical groove.

Claim 20

A fastener for attaching insulation to a roof deck, said fastener comprising a plastic retaining member having a top portion with an upper surface and a lower surface, a hub integral with said top portion and extending downwardly from the lower surface of said top portion and a helical coil having a plurality of loops extending downwardly from said hub having a helical groove formed therein having substantially the same pitch as said helical coil and at least the uppermost loops of said helical coil being located in said helical groove, the lower end of the lowermost loop of said helical coil being formed with a point lying on the center line of said helical coil and said lower end being substantially parallel to the center line of said helical coil and self-tapping threads formed along said lower end, whereby said helical coil is adapted to be screwed through the insulation into the roof deck and said self-tapping threads are adapted to pass through a pilot hole in a light gauge sheet metal roof deck to attach said fastener to the roof deck to hold the insulation onto the roof deck.

Claim 21

A fastener for attaching insulation to a roof deck, said fastener comprising a plastic retaining member having a top portion with an upper surface and a lower surface, a hub integral with said top portion and extending downwardly from the lower surface of said top portion and a helical coil having a plurality of loops extending downwardly from said hub having a helical groove formed therein having substantially the same pitch as said helical coil and at least the uppermost loops of said helical coil being located in said helical groove, the lower end of the lowermost loop of said helical coil being formed with a point lying on the center line of said helical coil and said lower end being substantially parallel to the center line of said helical coil and self-tapping threads formed along said lower end, whereby said helical coil is adapted to be screwed through the insulation into the roof deck and said self-tapping threads are adapted to pass through a pilot hole in a light gauge sheet metal roof deck to attach said fastener to the roof deck to hold the insulation onto the roof deck.

Claim 22

A fastener as set forth in claim 18 wherein said helical coil is substantially with a high spring rate and the lowermost loops of said helical coil are formed with a smaller diameter than the other loops of said helical coil.