Superelastic washer
AssigneeNitilock Ltd.
InventorsDvir Keren, Hadar Better
Life of this patent
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Abstract
Fastening apparatus includes a fastener (30, 64, 120), including a threaded shaft (34, 126) having a thread diameter and a fastening element (36, 68, 124) having a head diameter, greater than the thread diameter. An annular washer (38, 40, 66, 70, 90, 100, 110, 122), including a shape memory material, is configured to fit over and surround the shaft and has an outer diameter no greater than the head diameter.
Claims24
Fastening apparatus, comprising:
- a fastener comprising a threaded shaft having a thread diameter and a fastening element having a head diameter, greater than the thread diameter;
- and
- an annular washer, comprising a shape memory material, which is configured to fit over and surround the shaft so as to be compressed by the fastening element as the fastener is screwed into a socket and which has an outer diameter no greater than the head diameter.
A fastening device, comprising:
- a central ring made from a shape memory material and having a central axis;
- and
- an annular ancillary structure coupled to the ring and configured to engender a circumferential deformation of the central ring in response to an axial force exerted on the structure.
Apparatus for fixation, comprising:
- an implant, which is configured to be inserted into a bone and which comprises a threaded receptacle having a thread diameter;
- a fixture, which is configured to protrude outside the bone and comprises a socket for alignment with the threaded receptacle, the socket having a socket diameter greater than the thread diameter;
- a fastener comprising a threaded shaft, which is configured to be screwed into the threaded receptacle, and a head, which is sized so as to fit closely inside the socket;
- and
- an annular washer, comprising a shape memory material, which is configured and sized to fit inside the socket while surrounding the shaft of the fastener so as to be compressed by the head as the fastener is screwed into the socket.
A method for closing a fastener that includes a threaded shaft having a thread diameter and a fastening element having a head diameter, greater than the thread diameter, the method comprising:
- fitting an annular washer, which comprises a shape memory material and has an outer diameter no greater than the head diameter, over the threaded shaft of the fastener;
- and
- turning the fastening element so that the fastening element compresses the washer as the fastener is closed.
A fastening device, including an annular structure, which includes an elastic element and which is configured to fit over a shaft of a threaded fastener and to create a tension in the elastic element in response to an axial force exerted on the device as the fastener is tightened.
Dependencies are inferred from the claim text.