# US 2014/0150580 A1 · Rotary to linear transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150580 A1 - Document ID: US20140150580A1 - Status: Published application - Kind: A1 - Application number: 14/082,160 - Filed: 2013-11-17 - Published: 2014-06-05 - Earliest claimed: 2012-12-01 - Inventors: John McEntee - Web page: https://patentgrep.com/patent/US20140150580A1 ## CPC - F16H 25/2233: {with cages or means to hold the balls in position} - F16H 25/2204: {with balls} - F16H 25/2228: {the device for circulation forming a part of the screw member} - Y10T 74/18664: Shaft moves through rotary drive means - F16H: GEARING - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An apparatus for converting rotary motion to linear motion comprising: a cylindrical bore; a plurality of balls of uniform radius. The apparatus further comprises a rotor element, The rotor element further comprising a helical groove on the perimeter of the rotor element, wherein the helical groove comprises two ends and a race, wherein the race is configured to hold the plurality of balls in contact with a surface of the bore and is further configured to roll the ball in a helical groove path. The apparatus further comprises a recirculation conduit joining the two ends of the helical groove, wherein the conduit is configured to create a path for the plurality of balls and is further configured to allow the plurality of balls to remain in the helical groove during rotation of the rotor element. ## Claims ### Claim 1 An apparatus for converting rotary motion to linear motion comprising: a cylindrical bore; a plurality of balls of uniform radius; a rotor element comprising a helical groove on a perimeter of the rotor element, wherein the helical groove comprises two ends and a race, wherein the race is configured to hold the plurality of balls in contact with a surface of the bore and is further configured to roll the ball in a helical groove path; and a recirculation conduit joining the two ends of the helical groove, wherein the conduit is configured to create a conduit path for the plurality of balls and is further configured to allow the plurality of balls to remain in the helical groove during rotation of the rotor element. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the helical groove is cylindrical. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the helical groove path is less than 360 degrees. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the helical groove path comprises multiple wraps without interference between individual wraps. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the helical groove is v-shaped. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein a wall of the helical groove is convex. ### Claim 7 (depends on 5) The apparatus of claim 5, wherein a wall of the helical groove is concave. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the apparatus comprises: at least two cylindrical helical grooves, wherein each of the cylindrical helical grooves is of a v-shaped profile; and at least two interconnecting recirculation conduits. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein each of the three cylindrical helical grooves is comprised of a helical bevel. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the rotor element comprises two half sections and wherein the apparatus comprises a ball spacing ring. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the surface of the bore comprises a wall groove. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the wall groove is of a spiral shape configured to maximize repeatability. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the apparatus comprises at least one region configured to hold the plurality of balls in contact with a wall of the bore within a helical bevel region and further configured to guide the plurality of balls away from the bore wall during recirculation. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the rotor element comprises a double sided half section having a helical bevel region and a conduit. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein the rotor element is coupled to a structure at a center of the rotor element. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the structure is a spindle element. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein the structure is a linear actuator. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein the apparatus is coupled to an exterior cylindrical tube. ### Claim 19 (depends on 1) The apparatus of claim 1, wherein a cross section of the helical groove is rectangular shaped. ### Claim 20 (depends on 1) The apparatus of claim 1, wherein a cross section of the helical groove is circular shaped. ### Claim 21 (depends on 1) The apparatus of claim 1, wherein the helical groove is at a right handed direction ### Claim 22 (depends on 1) The apparatus of claim 1, wherein the helical groove is at a left handed direction. ### Claim 23 (depends on 5) The apparatus of claim 5, wherein an angle of a side of the v-shaped groove is configured to increase traction of the plurality of balls against a wall of the bore upon increase in an axial force on the rotor element. ### Claim 24 An apparatus for converting rotary motion to linear motion comprising: a cylindrical bore; a plurality of balls of uniform radius; a rotor element comprising a helical groove on a perimeter of the rotor element, wherein the helical groove comprises two ends and a race, wherein the race is configured to hold the plurality of balls in contact with a surface of the bore and is further configured to roll the ball in a helical groove path, and further wherein the rotor element comprises two half sections; and a recirculation conduit joining the two ends of the helical groove, wherein the conduit is configured to create a conduit path for the plurality of balls and is further configured to allow the plurality of balls to remain in the helical groove during rotation of the rotor element. ### Claim 25 An apparatus for converting rotary motion to linear motion comprising: a cylindrical bore; a plurality of balls of uniform radius; a rotor element comprising a helical groove on a perimeter of the rotor element, wherein the helical groove comprises two ends and a race, wherein the race is configured to hold the plurality of balls in contact with a surface of the bore and is further configured to roll the ball in a helical groove path; a ball spacing ring coupled to the rotor element; and a recirculation conduit joining the two ends of the helical groove, wherein the conduit is configured to create a conduit path for the plurality of balls and is further configured to allow the plurality of balls to remain in the helical groove during rotation of the rotor element.