# US 2021/0079986 A1 · Fixed ratio traction or friction drive > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0079986 A1 - Document ID: US20210079986A1 - Status: Published application - Kind: A1 - Application number: 16/962,447 - Filed: 2019-06-03 - Published: 2021-03-18 - Earliest claimed: 2018-06-06 - Assignees: Vectis Drive Inc. - Applicants: Vectis Drive Inc. - Inventors: Philippe FAUTEUX - Web page: https://patentgrep.com/patent/US20210079986A1 ## CPC - F16H 13/06: with members having orbital motion - F16H 13/08: with balls or with rollers acting in a similar manner - F16H 13/10: Means for influencing the pressure between the members - F16H 57/082: {Planet carriers} - F16H 2057/085: {Bearings for orbital gears} - F16H: GEARING ## Abstract There is described a multistage friction/traction speed adapter. A first drive can include a plurality of free rollers orbiting around a sun element within a frame, transmitting their orbiting movement to guided rollers which do not contact the sun element or the frame. The guided rollers are driven in the orbiting movement and transmit the rotary movement to a carrier via corresponding pins which engage with the carrier. A second drive can include rollers having radial position variation which is prevented from being transmitted to the carrier by providing accommodation at the pin level, either by providing a bushing around the pins with a bore that is eccentric relative to its outer surface, either by engaging the pins into the carriers in portions thereof which are made more flexible. A friction/traction gear at an angle is also disclosed. ## Claims ### Claim 1 A speed-adapter drive to be inserted in a fixed frame and comprising: a sun element; at least three planet elements provided around the sun element and in rolling contact therewith for orbiting, and confined within the fixed frame to guide the orbiting, thus providing a fixed gear ratio for the speed-adapter drive, and in rolling contact with an inner surface of the fixed frame, wherein the at least three planet elements are in rolling contact with the sun element, the sun element and the planet elements having a smooth surface such that all rolling contacts are friction contacts or traction contacts and are toothless; and guided rollers in rolling contact with the at least three planet elements, but not in rolling contact with the sun element or the fixed frame, the orbiting of the at least three planet elements driving a corresponding orbiting of the guided rollers around the sun element to output a rotary movement with the fixed gear ratio for the speed-adapter drive, wherein the fixed frame is a cylinder concentric with the sun element, and the rolling contacts between the guided rollers and the at least three planet elements are preloaded to eliminate backlash. ### Claim 2 (depends on 1) The speed-adapter drive of claim 1, wherein the at least three planet elements in rolling contact with the sun element are free rollers in rolling contact with both the sun element and the inner surface of the fixed frame, wherein the rolling contact comprises a friction contact or a traction contact. ### Claim 3 (depends on 2) The speed-adapter drive of claim 2, wherein the free rollers comprise bores having diameters selected so that preload contact forces with the sun element, the fixed frame and the guided rollers are controlled. ### Claim 4 (depends on 3) The speed-adapter drive of claim 3, wherein the sun element defines a longitudinal axis along which it extends, further comprising pins corresponding to the guided rollers, each one of the pins extending in the longitudinal axis through each one of the guided rollers corresponding thereto, each one of the pins maintaining the guided rollers corresponding thereto in a radial position about the sun element, the pins being used, under the orbiting of the guided rollers, to output the rotary movement of the orbiting guided rollers. ### Claim 5 (depends on 4) The speed-adapter drive of claim 4, further comprising a carrier into which the pins from the guided rollers engage, the carrier acting as an output for the speed-adapter drive. ### Claim 6 A speed-adapter drive to be inserted in a fixed frame and comprising: a sun element defining a longitudinal axis along which it extends; at least three planet elements provided around the sun element and in rolling contact therewith for orbiting, and confined within the fixed frame to guide the orbiting, and in rolling contact with an inner surface of the fixed frame, wherein the at least three planet elements are in rolling contact with the sun element, the sun element and the planet elements having a smooth surface such that all rolling contacts are friction contacts or traction contacts and are toothless, the orbiting of the at least three planet elements providing a rotary movement with a fixed-ratio drive reduction; pins corresponding to the at least three planet elements, each one of the pins extending in the longitudinal axis through each one of the at least three planet elements corresponding thereto, each one of the pins maintaining the at least three planet elements corresponding thereto in a radial position about the sun element, the pins being used, under the orbiting of the at least three planet elements, to output the rotary movement of the orbiting at least three planet elements; a carrier into which the pins from the at least three planet elements engage, the carrier acting as an output for the speed-adapter drive; and an accommodation for the pins to allow for a variation of the radial position of at least one of the at least three planet elements during the orbiting thereof without transmitting the variation of the radial position to the carrier, wherein the accommodation comprises providing a bushing inside the at least three planet elements, the bushing for each of the at least three planet elements having a bore having a central bore axis which is parallel but not coincident with a central longitudinal axis of a corresponding one of the at least three planet elements, allowing a movement of the central longitudinal axis of the at least three planet elements around the bore central axis of the bushing during their orbiting, the movement not being transmitted to the pins, the bushing comprising an external cylindrical surface, a center thereof defining the central longitudinal axis with which the central bore axis is parallel but not coincident, the bushing inside each one of the at least three planet elements being therefore eccentric. ### Claim 7 A speed-adapter drive to be inserted in a fixed frame and comprising: a sun element defining a longitudinal axis along which it extends; at least three planet elements provided around the sun element and in rolling contact therewith for orbiting, and confined within the fixed frame to guide the orbiting, and in rolling contact with an inner surface of the fixed frame, wherein the at least three planet elements are in rolling contact with the sun element, the sun element and the planet elements having a smooth surface such that all rolling contacts are friction contacts or traction contacts and are toothless, the orbiting of the at least three planet elements providing a rotary movement with a fixed-ratio drive reduction; pins corresponding to the at least three planet elements, each one of the pins extending in the longitudinal axis through each one of the at least three planet elements corresponding thereto, each one of the pins maintaining the at least three planet elements corresponding thereto in a radial position about the sun element, the pins being used, under the orbiting of the at least three planet elements, to output the rotary movement of the orbiting at least three planet elements; a carrier into which the pins from the at least three planet elements engage, the carrier acting as an output for the speed-adapter drive; and an accommodation for the pins to allow for a variation of the radial position of at least one of the at least three planet elements during the orbiting thereof without transmitting the variation of the radial position to the carrier, wherein the carrier comprising a plurality of engagement portions into which the corresponding pins engage, the accommodation comprising an opening being provided about each of the plurality of engagement portions to make the engagement portions flexible and allow the variation of the radial position of the pins which is not transmitted to the carrier. ### Claim 8 (depends on 6) The speed-adapter drive of claim 6, wherein the fixed frame is a cylinder concentric with the sun element. ### Claim 9 (depends on 6) The speed-adapter drive of claim 6, wherein the carrier acts as an output for the speed-adapter drive for a multi-stage arrangement. ### Claim 10 (depends on 6) The speed-adapter drive of claim 6, wherein the sun element is hollow to provide elasticity. ### Claim 11 (depends on 1) The speed-adapter drive of claim 1, further comprising a circular groove on an internal surface of the fixed frame to increase a contact pressure between the rollers and the frame and to promote solidification of a traction fluid. ### Claim 12 (depends on 1, 6) The speed-adapter drive of claim 1, namely a first speed-adapter drive, in combination with: a fixed frame; and a second speed-adapter drive according to claim 6; wherein the first speed-adapter drive and the second speed-adapter drive are connected in series within the fixed frame. ### Claim 13 (depends on 1) The speed-adapter drive of claim 1, further comprising an elbow speed-adapter drive comprising: a first traction or friction gear element comprising a revolution surface and a first traction or friction gear axis; a second traction or friction gear element, with its rotation axis at an angle relative to the first traction or friction gear axis in a range between 45° and 135° and comprising a revolution surface; wherein the first traction or friction gear and the second traction or friction gear are urged together at their respective revolution surface by a biasing device to provide a rolling contact surface which is toothless. ### Claim 14 (depends on 13) The speed-adapter drive of claim 13, wherein at least one of: the revolution surface of the first traction or friction gear element; and the revolution surface of the second traction or friction gear element is convex at the rolling contact surface in a plane that includes the first traction or friction gear axis and the rotation axis of the second traction or friction gear element. ### Claim 15 (depends on 14) The speed-adapter drive of claim 14, wherein the rolling contact surface defines a plane which is tangent with the at least one revolution surface which is convex, wherein the plane coincides with an intersection of the first traction or friction gear axis and the second traction or friction gear axis. ### Claim 16 (depends on 15) The speed-adapter drive of claim 15, wherein the biasing device is a spring used on the first traction or friction gear element or on the second traction or friction gear element, for a longitudinal biasing thereof along the first traction or friction gear axis or the second traction or friction gear axis, respectively. ### Claim 17 (canceled) ### Claim 18 (depends on 7) The speed-adapter drive of claim 7, wherein the sun element is hollow to provide elasticity. ### Claim 19 (depends on 1, 7) The speed-adapter drive of claim 1, namely a first speed-adapter drive, in combination with: a fixed frame; and a second speed-adapter drive according to claim 7; wherein the first speed-adapter drive and the second speed-adapter drive are connected in series within the fixed frame. ### Claim 20 (depends on 6) The speed-adapter drive of claim 6, further comprising an elbow speed-adapter drive comprising: a first traction or friction gear element comprising a revolution surface and a first traction or friction gear axis; a second traction or friction gear element, with its rotation axis at an angle relative to the first traction or friction gear axis in a range between 45° and 135° and comprising a revolution surface; wherein the first traction or friction gear and the second traction or friction gear are urged together at their respective revolution surface by a biasing device to provide a rolling contact surface which is toothless. ### Claim 21 (depends on 7) The speed-adapter drive of claim 7, further comprising an elbow speed-adapter drive comprising: a first traction or friction gear element comprising a revolution surface and a first traction or friction gear axis; a second traction or friction gear element, with its rotation axis at an angle relative to the first traction or friction gear axis in a range between 45° and 135° and comprising a revolution surface; wherein the first traction or friction gear and the second traction or friction gear are urged together at their respective revolution surface by a biasing device to provide a rolling contact surface which is toothless.