1. A locking spring screw, comprising:
a cylindrical screw body;
a flexible spring member; and,
a screw head attached to the cylindrical screw body, wherein the screw head comprises
a tool slot adapted for receipt of the spring member,
at least one outlet adjacent to the tool slot adapted for passage therethrough of a tongue of the spring member, and,
a ridge located opposite the at least one outlet from the cylindrical screw body and at least partially around the circumference of the screw head.
2. A spring screw according to claim 1, wherein the cylindrical screw body is threaded.
3. A spring screw according to claim 1, wherein the tongue of the spring member and the ridge form a slot when the tongue is passed through the outlet.
4. A spring screw according to claim 1, wherein the length of the spring member is correlated to the amount of spring member flex allowed by a floor of the tool slot such that upon maximum flex of the spring member towards the floor, the tongue retracts at least partially into outlet.
5. A spring screw according to claim 4, wherein maximum flex is no more than 20 thousandths of an inch.
6. A spring screw according to claim 1, wherein the tool slot and the spring member are formed as counterparts.
7. A spring screw according to claim 1, wherein the tongue and outlet diameter are narrower than the spring member.
8. A spring screw according to claim 1, wherein the ridge is sloped, increasing in size moving away from the cylindrical screw body.
9. A spring screw according to claim 1, wherein at least one of the flexible spring member, cylindrical screw body and screw head are constructed of at least one of titanium, stainless steel, cobalt chrome, ceramic, polymer, or PEEK Optima.
10. A spring screw according to claim 1, wherein the screw length along its central axis is 8.0 mm-60.0 mm.
11. A spring screw according to claim 1, wherein the screw head is 3.5 mm-9.0 mm in diameter.
12. A system for interlocking a screw and an implant wherein the screw has motion in only one degree of freedom, comprising:
an implant provided with at least one screw hole provided with a flange; and,
a spring screw comprising a flexible spring member, and, a screw head attached to the cylindrical screw body, wherein the screw head comprises a tool slot adapted for receipt of the spring member, at least one outlet adjacent to the tool slot adapted for passage therethrough of a tongue of the spring member, and, a ridge located opposite the at least one outlet from the cylindrical screw body and at least partially around the circumference of the screw head,
wherein when the spring member is un-flexed the tongue and the ridge form a flange slot adapted for receipt of the flange therein.
13. A system according to claim 12, further comprising a tool adapted to be a counterpart to the tool slot.
14. A system according to claim 13, wherein the tool is provided with a tool hub for flexing the spring member upon insertion of the tool into the tool slot.
15. A system according to claim 13, wherein the tool is provided with at least one ridge for providing torque to the spring screw for attaching the spring screw to the implantation site.
16. A system according to claim 12, wherein the length of the spring member is correlated to the amount of spring member flex allowed by a floor of the tool slot such that upon maximum flex of the spring member towards the floor, the tongue retracts at least partially into outlet allowing tongue to pass flange.
17. A system according to claim 12, wherein the one degree of freedom is around a central axis of the spring screw.
18. A method of using a spring screw provided with a spring member to secure an implantable device to an implantation site, comprising:
inserting the spring screw in a screw hole located on the implantable device while the spring member is flexed towards the floor of a tool slot in the screw head using a tool;
advancing the spring screw until a ridge of the screw head abuts a flange of the screw hole;
driving the spring screw into the implantation site;
retracting the tool from the spring screw, resulting in expansion of the spring member such that a tongue portion of the spring member extends out of an outlet in the screw head, trapping the flange of the screw hole in a flange slot formed in between the tongue portion of the spring member and the ridge of the screw head.
19. A method according to claim 18, further comprising repeating inserting, advancing, driving and retracting for a plurality of spring screws.
20. A method according to claim 18, wherein trapping the flange of the screw in the flange slot substantially restricts the spring screw to movement in only one degree of freedom, around its central axis.
21. A method according to claim 18, wherein the implantation site is at least one of a vertebra, a pedicle of the vertebra, a facet of the vertebra, or a lateral mass of the vertebra.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A propeller for an outboard motor fixed to a rear portion of a propeller shaft pivotally supported in an anteroposterior direction of a hull to which the outboard motor is mounted on a lower portion of the outboard motor, comprising:
a cylindrically formed propeller hub; and
a plurality of blades provided radially on an outer side of the propeller hub, and having surfaces of the blades to which a shot-peening treatment is applied.
2. The propeller for an outboard motor according to claim 1, wherein the each of blades has a blade body having a surface of which the shot-peening treatment is applied.
3. The propeller for an outboard motor according to claim 1, wherein the each of blades has a blade root portion having a surface of which the shot-peening treatment is applied.
4. The propeller for an outboard motor according to claim 1, wherein the shot-peening treatment for mirror finishing is applied.
5. The propeller for an outboard motor according to claim 1, wherein the propeller is formed of a metal material having a surface on which an oxide coating is formed by heating the metal material forming the propeller.
6. The propeller for an outboard motor according to claim 5, wherein the metal member forming the propeller contains at least one material of titanium, stainless steel and copper.
7. The propeller for an outboard motor according to claim 5, wherein the metal member forming the propeller is subjected to mirror finishing by a shot-peening treatment before the oxide coating is formed.