Self-locking composite-composite joints
A fastener free joining system includes a first tubular shell component having a first plurality of teeth defined in a first free end, each tooth extending along a respective tooth axis oblique to an axis of the first component by an angle α. The first plurality of teeth is configured to engage with a plurality of complimentary teeth defined in a second free end of a second tubular shell component, such that, when engaged, the first plurality of teeth is configured to remain engaged with the plurality of complimentary teeth under axial load.
1. A fastener free joining system, comprising:
a first polymer-based tubular component defining a first axis and having a first plurality of teeth defined in a first free end thereof, each tooth extending along a respective tooth axis angled oblique to the first axis by an angle α;
a second polymer-based tubular component defining a second axis and having a second plurality of teeth defined in a second free end thereof, each tooth extending along a respective tooth axis angled oblique to the second axis by the angle α,
wherein the second plurality of teeth are complementary to the first plurality of teeth and configured to engage with the first plurality of teeth to join the first component and the second components coaxially to form a joint therebetween such that, when engaged, the first component and second component remain engaged under tensile axial load; and
an external ring configured to interface with an outer surface of a portion of the first tubular component and an outer surface of a portion of the second tubular component at a location over the joint;
wherein at least the first component further includes a first wedge portion defined on the outer surface, the first wedge portion defined by a linearly non-uniform diameter, and wherein the ring includes a generally complementary inner diameter profile configured to interface with the first wedge portion to provide contact pressure to the joint.
2. The system of claim 1 , wherein the first component and/or the second component is a fiber-reinforced polymer-matrix composite.
3. The system of claim 2 , wherein contact surfaces of the first plurality of teeth and the second plurality of teeth are joined by one or more of: adhesive, co-curing, and welding.
4. The system of claim 3 , wherein the first component and second component are configured to form an aircraft water collector.
5. The system of claim 1 , wherein the second component further comprises a second wedge portion defined in the outer surface, the second wedge portion defined by a linearly non-uniform diameter and axially aligned with the first wedge portion of the first component to form a contiguous wedge structure, wherein the ring includes a generally complementary inner diameter profile configured to interface with the contiguous wedge structure to provide contact pressure to the joint.
6. The system of claim 1 , wherein the second component further includes a second wedge portion defined in the outer surface thereof, the second wedge portion defined by a linearly non-uniform diameter and facing opposite the first wedge portion to form a peak therebetween, wherein the ring includes first ring portion having a complementary inner diameter profile configured to interface with the first wedge portion and a second ring portion having a complementary inner diameter profile configured to interface with the second wedge portion, the first and second ring portions configured to meet at the peak to provide contact pressure to the joint.
7. The system of claim 1 , wherein the angle a between the respective tooth axis and first axis and between the respective tooth axis and the second axis constant along a length of a respective tooth.
8. The system of claim 1 , wherein the angle a between the respective tooth axis and first axis and between the respective tooth axis and the second axis is variable along a length of a respective tooth.
9. The system of claim 1 , wherein each tooth has a thickness equal to or less than a thickness of the respective first component and second component and a width that is uniform along the respective tooth axis from a base of the tooth to a tip of the tooth.
10. The system of claim 1 , wherein a geometry of each tooth is non-uniform along the respective tooth axis from a base of the tooth to a tip of the tooth.
11. The system of claim 1 , wherein each tooth of the first plurality of teeth is defined through an entire radial thickness of the first component and each tooth of the second plurality of teeth is defined through an entire radial thickness of the second component.
12. The system of claim 1 , wherein each tooth of the first plurality of teeth is defined through a portion of a radial thickness of the first component and each tooth of the second plurality of teeth is defined through a portion of a radial thickness of the second component.
13. A method of forming a component, comprising, forming a first polymer-based tubular component defining a first axis and having a first plurality of teeth defined in a first free end thereof, each tooth extending along a respective tooth axis angled oblique to the first axis by an angle α;
forming a second polymer-based tubular component defining a second axis and having a second plurality of teeth defined in a second free end thereof, each tooth extending along a respective tooth axis angled oblique to the second axis by the angle α, the second plurality of teeth complementary to the first plurality of teeth;
engaging the first plurality of teeth with the second plurality of teeth to join the first component and the second component coaxially to form a joint therebetween such that, when engaged, the first component and second component remain engaged under tensile axial load; and
installing a ring on an outer surface of a portion of the first component and the second component at the joint to provide contact pressure to the joint;
wherein installing the ring includes installing the ring on a wedge structure defined on at least one of the first and or second component.
14. The method of claim 13 , wherein installing the ring includes thermally shrinking the first and second components before installing the ring and allowing the first and second components to thermally expand into the ring such that the ring provides contact pressure to the joint.
15. The method of claim 13 , wherein installing the ring includes installing a first ring portion over a first wedge structure defined in the first component and a second ring portion over a second wedge structure defined on the second component.
16. A method, comprising, forming a first tubular component defining a first axis and having a first plurality of teeth defined in a first free end thereof, each tooth extending along a respective tooth axis angled oblique to the first axis by an angle α;
forming a second tubular component defining a second axis and having a second plurality of teeth defined in a second free end thereof, each tooth extending along a respective tooth axis angled oblique to the second axis by the angle α, the second plurality of teeth complementary to the first plurality of teeth;
engaging contact surfaces of the first plurality of teeth with contact surfaces of the second plurality of teeth to join the first component and the second component coaxially to form a joint therebetween such that, when engaged, the first component and second component remain engaged under tensile axial load; and
installing a ring on an outer surface of a portion of the first component and the second component at the joint to provide contact pressure to the joint, wherein installing the ring includes thermally shrinking the first and second components before installing the ring and allowing the first and second components to thermally expand into the ring such that the ring provides contact pressure to the joint.