# US 6,296,417 B1 · Circlips > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,296,417 B1 - Document ID: US6296417B1 - Status: Granted - Kind: B1 - Application number: 09/158,096 - Filed: 1998-09-22 - Granted: 2001-10-02 - Earliest claimed: 1996-03-22 - Assignees: Sustainable Engine Systems Limited - Inventors: Richard F. Kinnersly - Web page: https://patentgrep.com/patent/US6296417B1 ## CPC - F16B 21/18: with circlips or like resilient retaining devices, {i.e. resilient in the plane of the ring or the like}; Details (spring-washers for locking nuts F16B39/24; adjusting rings F16B43/00) - Y10S 403/07: Split ring stop or abutment - Y10T 403/7049: Biased by distinct radially acting means - F16B: DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING (couplings for transmitting rotation F16D) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A circlip (8) comprises a band of material forming an incomplete ring, and has curved bearing surfaces (10, 11) at opposite ends of the major transverse dimension of the band. The major transverse dimension is generally oriented at less than 90°, and preferably a small acute angle α, to the central axis A of the ring in the unstressed state of the circlip (8). ## Claims ### Claim 1 A circlip comprising a band of material in part-conical form forming an incomplete ring, said band having a transverse major dimension along a major axis and having a central axis, and having bearing surfaces located at opposite ends of said dimension of the band, said bearing surfaces curved in transverse cross-section wherein said dimension is at an angle of less than about 45° with respect to the central axis when in an unstressed state of the circlip. ### Claim 2 (depends on 1) A circlip as claimed in claim 1 wherein the curved bearing surfaces are convex. ### Claim 3 (depends on 1) A circlip as claimed in claim 1 wherein the bearing surfaces are part-circular in transverse cross-section. ### Claim 4 (depends on 1) A circlip as claimed in claim 1 wherein the bearing surfaces have substantially the same radius of curvature. ### Claim 5 (depends on 1) A circlip as claimed in claim 1 wherein the bearing surfaces are substantially continuous around a circumferential extent of the circlip. ### Claim 6 (depends on 1) A circlip as claimed in claim 1 wherein the said major dimension is at an angle of less than about 15° to the central axis. ### Claim 7 (depends on 1) A circlip as claimed in claim 1 wherein the transverse band cross-section has substantially straight, parallel major sides and is substantially symmetrical about the major axis thereof. ### Claim 8 (depends on 1) A circlip as claimed in claim 1 wherein the band has vent apertures therein. ### Claim 9 Apparatus for connecting first and second members, the apparatus comprising: a male portion of the first member; a female portion of the second member for reception of the male portion of the first member; and a circlip comprising a band of material in part-conical form forming an incomplete ring, said band having a transverse major dimension along a major axis and having a central axis, and having bearing surfaces located at opposite ends of said dimension of the band, said bearing surfaces curved in transverse cross-section. wherein said dimension is at an anole of less than 90° with respect to the central axis when in an unstressed state of the circlip; wherein the male and female portions have respective annular regions for abutting the bearing surfaces at opposite ends of the major transverse dimension of the circlip, whereby, in use, the circlip inhibits relative axial displacement of said portions tending to compress the circlip. ### Claim 10 (depends on 9) Apparatus as claimed in claim 9, wherein the annular regions are annular recesses for receiving the respective bearing surfaces of the circlip. ### Claim 11 (depends on 9) Apparatus as claimed in claim 9 wherein at least one of the male and female portions has an abutment surface adjacent the annular region for inhibiting dislocation of the bearing surfaces of the circlip from the annular region. ### Claim 12 (depends on 9) Apparatus as claimed in claim 9 wherein the annular regions are curved in transverse cross-section. ### Claim 13 (depends on 12) Apparatus as claimed in claim 12 wherein the annular regions are part-circular in transverse cross-section. ### Claim 14 (depends on 13) Apparatus as claimed in claim 13 wherein the radius of curvature of each annular region is substantially equal to a radius of curvature of the corresponding bearing surface. ### Claim 15 (depends on 14) Apparatus as claimed in claim 14 wherein, in transverse cross-section, the angle subtended by the ends of the curved surface of each annular region is greater than the angle subtended by the ends of the corresponding bearing surface. ### Claim 16 (depends on 9) Apparatus as claimed in claim 9 wherein the angle of said major dimension to the central axis of the circlip in the unstressed state is greater than the corresponding angle when the apparatus is assembled with the bearing surfaces of the circlip abutting the annular regions of the male and female portions, whereby the circlip is biased into engagement with the male and female portions in the assembled state. ### Claim 17 (depends on 9) Apparatus as claimed in claim 9 including resilient means located between the male and female portions for inhibiting relative axial displacement of the male and female portions in the opposite direction to the relative displacement inhibited by the circlip. ### Claim 18 (depends on 9) Apparatus as claimed in claim 9 wherein the first and second members are components of a Stirling engine. ### Claim 19 (depends on 18) Apparatus as claimed in claim 18 wherein the second member comprises an engine cylinder of said Stirling engine, the female portion comprising a cylinder mouth, and wherein the first member comprises a cylinder head, and the male portion comprising a base flange of the cylinder head. ### Claim 20 Apparatus for connecting first and second members, the apparatus comprising: a male portion of the first member; a female portion of the second member for reception of the male portion of the first member; and a circlip comprising a band of material forming an incomplete ring, and having, at opposite ends of a major transverse dimension of the band, bearing surfaces which are curved in transverse cross-section, wherein said major transverse dimension is generally oriented at less than 90° to a central axis of the ring in an unstressed state; wherein the male and female portions have respective annular regions for abutting the bearing surfaces at opposite ends of the major transverse dimension of the circlip, whereby, in use, the circlip inhibits relative axial displacement of said portions tending to compress the circlip, wherein the angle of said major transverse dimension to the central axis of the circlip in the unstressed state is greater than the corresponding angle when the apparatus is assembled with the bearing surfaces of the circlip abutting the annular regions of the male and female portions, whereby the circlip is biased into engagement with the male and female portions in the assembled state. ### Claim 21 A circlip comprising a band of material in part-conical form forming an incomplete ring, said ring having two ends and a gap between said ends, said band having a transverse major dimension along a major axis and having a central axis, and having bearing surfaces located at opposite ends of said dimension of the band, said bearing surfaces curved in transverse cross-section, wherein said dimension is at an angle of less than 90° with respect to the central axis when in an unstressed state of the circlip.