# US 10,371,201 B2 · Speed reducer and method of assembling such a reducer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,201 B2 - Document ID: US10371201B2 - Status: Granted - Kind: B2 - Application number: 15/768,906 - Filed: 2016-10-18 - Published: 2019-03-14 - Granted: 2019-08-06 - Earliest claimed: 2015-10-20 - Applicants: Moteurs Leroy-Somer - Inventors: Pascal Pont - Web page: https://patentgrep.com/patent/US10371201B2 ## CPC - F16C 25/083: {with resilient means acting axially on a race ring to preload the bearing} - F16C 19/386: {in O-arrangement} - F16C 33/60: divided {or split, e.g. comprising two juxtaposed rings} - F16C 35/063: Fixing them on the shaft (with interposition of an element F16C35/07) - F16C 35/067: Fixing them in a housing (with interposition of an element F16C35/07) - F16H 1/14: comprising conical gears only - F16C 2380/26: Dynamo-electric machines or combinations therewith, e.g. electro-motors and generators - F16H 2057/0221: {Axial adjustment} - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - F16H: GEARING ## Abstract A speed reducer including a shaft extending along an axis, two rolling bearings arranged around the shaft, the two rolling bearings each including a radially outer ring, a radially inner ring and rolling elements arranged between the outer and inner rings. The speed reducer includes a preload system positioned between the two rolling bearings and which includes: two spacer elements each one resting against one of the rings of the rolling bearings, at least one elastically deformable element interposed between the two spacing elements, and configured to occupy a preloaded first state and an least partially relaxed second state, the preload system arranged such that the transition of the at least one elastically deformable element from the first to the second state causes a unidirectional rotational movement of each spacer element with respect to the other so as to use a wedge effect to generate preload in the rolling bearings. ## Claims ### Claim 1 A speed reducer comprising a shaft extending along a longitudinal axis, two rolling bearings arranged around the shaft, the two rolling bearings each comprising a radially outer ring, a radially inner ring and rolling elements arranged between the radially outer and inner rings, characterized in that it comprises a preload system positioned in the gap between the two rolling bearings, the preload system comprising: two spacer elements each in bearing engagement with one of the rings of the rolling bearings, at least one elastically deformable element interposed between the two spacer elements, said at least one elastically deformable element is configured to be able to occupy a first prestressed state and a second at least partially relaxed state, the preload system being designed such that the transition of said at least one elastically deformable element from the first state to the second state causes a unidirectional rotational movement of each spacer element with respect to the other so as to generate, by a wedge effect, a preload in the rolling bearings. ### Claim 2 (depends on 1) The reducer as claimed in claim 1, wherein each spacer element is in bearing engagement only with the radially outer ring of the associated rolling bearing. ### Claim 3 (depends on 1) The reducer as claimed in claim 1, wherein each spacer element is only in bearing engagement against the radially inner ring of the associated rolling bearing. ### Claim 4 (depends on 1) The reducer as claimed in claim 1, wherein each spacer element has an outer face for bearing engagement against one of the rolling bearings and an inner face, opposed to the outer face, in contact with said at least one elastically deformable element, the inner face having at least one housing for said elastically deformable element such that said elastically deformable element exerts, during the transition from the first state to the second state, a tangential force on the inner face. ### Claim 5 (depends on 4) The reducer as claimed in claim 4, wherein the inner face is at least partially helical, with a substantially complementary shape to that of the other spacer element apart from the housing of said at least one elastically deformable element. ### Claim 6 (depends on 4) The reducer as claimed in claim 4, wherein the inner face of each spacer element forming a smooth or notched surface. ### Claim 7 (depends on 1) The reducer as claimed in claim 1, wherein at least the inner face of each spacer element is produced from a material such as steel and has a coefficient of friction between 0.05 and 0.6. ### Claim 8 (depends on 1) The reducer as claimed in claim 1, wherein the two spacer elements are identical. ### Claim 9 (depends on 1) The reducer as claimed in claim 1, wherein said at least one elastically deformable element is a spring chosen from the group consisting of compression springs, tension springs and torsion springs. ### Claim 10 (depends on 9) The reducer as claimed in claim 9, wherein said at least one elastically deformable element is a compression spring. ### Claim 11 (depends on 1) The reducer as claimed in claim 1, wherein said at least on elastically deformable element comprises a number of elastically deformable elements number of elastically deformable elements is greater than one, said elastically deformable elements being distributed between the spacer elements. ### Claim 12 (depends on 11) The reducer as claimed in claim 11, wherein the number of elastically deformable elements is between two and eight. ### Claim 13 (depends on 11) The reducer as claimed in claim 11, wherein the number of elastically deformable elements is equal to four. ### Claim 14 (depends on 11) The reducer as claimed in claim 11, wherein the number elastically deformable elements are distributed in a uniform manner between the spacer elements. ### Claim 15 (depends on 1) The reducer as claimed in claim 1, comprising a transmission, the transmission comprising a gear. ### Claim 16 (depends on 15) The reducer as claimed in claim 15, wherein the gear is spiral-conical, the shaft bearing a conical pinion. ### Claim 17 (depends on 1) The reducer as claimed in claim 1, the two rolling bearings consisting of conical rolling bearings with a so-called X setup or a so-called O setup, the radially inner and outer rings having an axially increasing or decreasing thickness, respectively. ### Claim 18 (depends on 1) The reducer as claimed in claim 1, comprising at least one axial blocking element arranged against each rolling bearing so as to prevent any axial movement of said rolling bearing away from the other rolling bearing, each axial blocking element comprising at least one shoulder formed on the shaft, a notched nut and/or a circlip or another type of axial blocking element. ### Claim 19 (depends on 1) A method for assembling a reducer as claimed in claim 1, comprising the following steps; mounting the preload system and the rolling bearings around the shaft so as to place said at least one elastically deformable element in the first stressed state, axially blocking the assembly of the rolling bearings and of the preload system, with the aid of axial blocking elements, so as to cause said at least one elastically deformable element to pass into the second at least partially relaxed state in order to generate a preload in the rolling bearings. ### Claim 20 (depends on 1) The reducer as claimed in claim 1, wherein at least the inner face of each spacer element has a coefficient of friction between 0.1 and 0.3.