In-situ molded fastener
View Patent ↗A method forming a fastener in-situ for fastening two parts at abutting surfaces. A through hole may be formed on each of the first and second parts such that the diameters of the through holes at the abutting surfaces are smaller than the diameters at opposing surfaces. The first and second parts are abutted with the through hole on the first part in fluid communication with the through hole on the second part. A flowable and hardenable material is injected into the first through hole while closing flow out of the second through hole. The flowable and hardenable material contained within the through holes is allowed to harden, thus forming a unitary fastener that fastens the parts.
1. A method, comprising:
selecting two parts to be fastened;
forming a through hole on each part between a first surface and an opposing second surface such that a dimension of each through hole at the first surface is larger than a dimension of the through hole at the opposing second surface;
abutting the two parts at the respective second surfaces with the through holes in fluid communication with each other;
injecting a flowable and hardenable material into the through holes of the two parts while preventing flow of the material out of the through holes; and
allowing the flowable and hardenable material to harden within the through holes.
2. The method of claim 1 , further comprising:
forcibly abutting the two parts by engaging a first platen with the first surface of one of the parts and simultaneously engaging a second platen with the first surface of the other part until the flowable and hardenable material has substantially hardened.
3. The method of claim 2 , further comprising:
positioning the first platen directly over the through hole on the part engaged by the first platen; and
flowing the flowable and hardenable material through a flow passage in the first platen and into the through holes.
4. The method of claim 3 , further comprising:
applying pressure to the flowable and hardenable material while the flowable and hardenable material hardens.
5. The method of claim 4 , further comprising:
applying a back pressure to the through hole on the part engaged by the second platen.
6. The method of claim 1 , further comprising:
forming the through holes along sheet-metal portions of the parts.
7. The method of claim 1 , wherein forming each through hole comprises tapering the through hole radially inwardly from the first surface to the second surface.
8. The method of claim 1 , further comprising:
forming the through holes on sheet metal portions of the parts.
9. The method of claim 1 , further comprising:
applying pressure to the flowable and hardenable material to up to thirty pounds per square inch while hardening.
10. The method of claim 1 , wherein the flowable and hardenable material is selected from the group consisting of a metal alloy and a thermoplastic material, wherein the flowable and hardenable material can be made flowable by heating and is hardenable by cooling.