# US 11,305,837 B2 · Bicycle rear sprocket assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,305,837 B2 - Document ID: US11305837B2 - Status: Granted - Kind: B2 - Application number: 15/799,984 - Filed: 2017-10-31 - Published: 2019-05-02 - Granted: 2022-04-19 - Earliest claimed: 2017-10-31 - Assignees: Shimano Inc. - Applicants: Shimano Inc. - Inventors: Atsushi Komatsu; Koji Yuasa; Takehiko Nakajima - Web page: https://patentgrep.com/patent/US11305837B2 ## CPC - B62M 9/12: the chain, belt, or the like being laterally shiftable {, e.g. using a rear derailleur} - F16D 1/10: Quick-acting couplings in which the parts are connected by simply bringing them together axially - F16H 55/30: Chain-wheels - F16H 57/0025: {with gearing elements rigidly connected to a shaft, e.g. securing gears or pulleys by specially adapted splines, keys or methods} - F16D 2001/103: {the torque is transmitted via splined connections} - B62M: RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR {SINGLE-TRACK} CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES (arrangements or mounting of transmissions in vehicles in general B60K; transmission elements per se F16) - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16H: GEARING ## Abstract A bicycle rear sprocket assembly comprises at least one sprocket and an internal cavity. The at least one sprocket includes at least ten internal spline teeth configured to engage with a bicycle hub assembly. The at least ten internal spline teeth have an internal-spline major diameter. The internal cavity has a maximum outer diameter larger than the internal-spline major diameter. ## Claims ### Claim 1 A bicycle rear sprocket assembly comprising: at least one sprocket including at least ten internal spline teeth configured to engage with a bicycle hub assembly, the at least ten internal spline teeth having an internal-spline major diameter; and an internal cavity having a maximum outer diameter larger than the internal-spline major diameter, the at least ten internal spline teeth including a plurality of internal-spline driving surfaces to transmit a driving rotational force to the bicycle hub assembly during pedaling, the plurality of internal-spline driving surfaces each including a radially outermost edge, a radially innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge, a total of the radial lengths of the plurality of internal-spline driving surfaces being equal to or larger than 7 mm, the internal-spline driving surface having a first internal-spline-surface angle defined between the internal-spline driving surface and a radial line extending from a rotational center axis of the bicycle rear sprocket assembly, the first internal-spline-surface angle ranging from 0 degree to 6 degrees, one tooth of the at least ten internal spline teeth has a first circumferential spline size, other teeth of the at least ten internal spline teeth each have a second circumferential spline size that is smaller than the first circumferential spline size, a total number of the other teeth of the at least ten external spline teeth being equal to or larger than nine,. one space circumferentially adjacent to the one tooth of the at least ten internal spline teeth has a first circumferential space size, and other spaces circumferentially adjacent to the other teeth of the at least ten internal spline teeth each have a second circumferential space size that is smaller than the first circumferential space size. ### Claim 2 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein a total number of the at least ten internal spline teeth is equal to or larger than 20. ### Claim 3 (depends on 2) The bicycle rear sprocket assembly according to claim 2, wherein the total number of the at least ten internal spline teeth is equal to or larger than 25. ### Claim 4 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein the at least ten internal spline teeth have a first internal pitch angle and a second internal pitch angle different from the first internal pitch angle. ### Claim 5 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein at least one of the at least ten internal spline teeth has a first spline shape different from a second spline shape of another of the at least ten internal spline teeth. ### Claim 6 A bicycle rear sprocket assembly comprising: at least one sprocket including a plurality of internal spline teeth configured to engage with a bicycle hub assembly, at least two internal spline teeth of the plurality of internal spline teeth being circumferentially arranged at a first internal pitch angle with respect to a rotational center axis of the bicycle rear sprocket assembly, the first internal pitch angle ranging from 10 degrees to 20 degrees, the plurality of internal spline teeth having an internal-spline major diameter; and an internal cavity having a maximum outer diameter larger than the internal-spline major diameter, the at least two internal spline teeth including a plurality of internal-spline driving surfaces to transmit a driving rotational force to the bicycle hub assembly during pedaling, the plurality of internal-spline driving surfaces each including a radially outermost edge, a radially innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge, a total of the radial lengths of the plurality of internal-spline driving surfaces being equal to or larger than 7 mm, the internal-spline driving surface having a first internal-spline-surface angle defined between the internal-spline driving surface and a radial line extending from the rotational center axis, the first internal-spline-surface angle ranging from 0 degree to 6 degrees, one tooth of the plurality of internal spline teeth has a first circumferential spline size, other teeth of the plurality of internal spline teeth each have a second circumferential spline size that is smaller than the first circumferential spline size, a total number of the other teeth of the plurality of external spline teeth being equal to or larger than nine,. one space circumferentially adjacent to the one tooth of the plurality of internal spline teeth has a first circumferential space size, and other spaces circumferentially adjacent to the other teeth of the plurality of internal spline teeth each have a second circumferential space size that is smaller than the first circumferential space size. ### Claim 7 (depends on 6) The bicycle rear sprocket assembly according to claim 6, wherein the first internal pitch angle ranges from 12 degrees to 15 degrees. ### Claim 8 (depends on 7) The bicycle rear sprocket assembly according to claim 7, wherein the first internal pitch angle ranges from 13 degrees to 14 degrees. ### Claim 9 (depends on 6) The bicycle rear sprocket assembly according to claim 6, wherein at least two internal spline teeth of the plurality of internal spline teeth are circumferentially arranged at a second internal pitch angle with respect to the rotational center axis, and the second internal pitch angle is different from the first internal pitch angle. ### Claim 10 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein the at least one sprocket includes a first sprocket, the first sprocket includes a first sprocket body and a plurality of first sprocket teeth extending radially outwardly from the first sprocket body relative to a rotational center axis of the bicycle rear sprocket assembly, and the first sprocket includes the plurality of internal spline teeth extending radially inwardly from the first sprocket body. ### Claim 11 (depends on 10) The bicycle rear sprocket assembly according to claim 10, wherein the first sprocket has a pitch-circle diameter larger than the maximum outer diameter of the internal cavity. ### Claim 12 (depends on 11) The bicycle rear sprocket assembly according to claim 11, wherein the pitch-circle diameter of the first sprocket is the largest pitch-circle diameter in the bicycle rear sprocket assembly. ### Claim 13 (depends on 10) The bicycle rear sprocket assembly according to claim 10, wherein the at least one sprocket includes a second sprocket, the second sprocket includes a second sprocket body and a plurality of second sprocket teeth extending radially outwardly from the second sprocket body relative to the rotational center axis, and the internal cavity is provided radially inwardly of the second sprocket body. ### Claim 14 (depends on 13) The bicycle rear sprocket assembly according to claim 13, wherein the first sprocket is a separate member from the second sprocket. ### Claim 15 (depends on 14) The bicycle rear sprocket assembly according to claim 14, further comprising a coupling member coupling the first sprocket to the second sprocket. ### Claim 16 (depends on 15) The bicycle rear sprocket assembly according to claim 15, wherein the coupling member is integrally provided with at least one of the first sprocket and the second sprocket as a one-piece unitary member. ### Claim 17 (depends on 16) The bicycle rear sprocket assembly according to claim 16, wherein the coupling member includes at least one coupling pin. ### Claim 18 (depends on 13) The bicycle rear sprocket assembly according to claim 13, wherein the plurality of first sprocket teeth and the plurality of second sprocket teeth are integrally provided with each other as a one-piece unitary member. ### Claim 19 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein the at least ten internal spline teeth have an internal-spline minor diameter, and the maximum outer diameter of the internal cavity is larger than the internal-spline minor diameter. ### Claim 20 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein at least one of the at least one sprocket includes a sprocket body and a plurality of sprocket teeth extending radially outwardly from the sprocket body relative to a rotational center axis of the bicycle rear sprocket assembly, and the plurality of sprocket teeth includes at least one first tooth and at least one second tooth, the at least one first tooth has a first maximum axial width defined in an axial direction relative to the rotational center axis, the at least one second tooth has a second maximum axial width defined in the axial direction, and the first maximum axial width is larger than the second maximum axial width. ### Claim 21 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein the at least one sprocket includes a smallest sprocket including at least one sprocket tooth, and a total number of the at least one sprocket tooth of the smallest sprocket is equal to or smaller than 10. ### Claim 22 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein the at least one sprocket includes a largest sprocket including at least one sprocket tooth, and a total number of the at least one sprocket tooth of the largest sprocket is equal to or larger than 46. ### Claim 23 (depends on 22) The bicycle rear sprocket assembly according to claim 22, wherein the total number of the at least one sprocket tooth of the largest sprocket is equal to or larger than 50. ### Claim 24 (depends on 1) The bicycle rear sprocket assembly according to claim 1, wherein a total number of the at least one sprocket is equal to or larger than 11.