# US 7,744,474 B2 · Propshaft assembly with stiffening ring and seal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,744,474 B2 - Document ID: US7744474B2 - Status: Granted - Kind: B2 - Application number: 11/386,602 - Filed: 2006-03-22 - Published: 2007-09-27 - Granted: 2010-06-29 - Earliest claimed: 2006-03-22 - Assignees: GKN Driveline North America, Inc. - Inventors: Brian Valovick - Web page: https://patentgrep.com/patent/US7744474B2 ## CPC - F16C 3/03: telescopic (axially displaceable couplings F16D3/06) - F16C 3/035: with built-in bearings - F16C 29/08: Arrangements for covering or protecting the ways {(protective coverings for parts of machine tools B23Q11/08)} - F16C 33/74: of sliding-contact bearings - F16D 1/101: {without axial retaining means rotating with the coupling} - F16D 3/845: {allowing relative movement of joint parts due to the flexing of the cover} - F16D 2001/103: {the torque is transmitted via splined connections} - Y10S 277/912: Spline connection - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A propshaft assembly has an inner tube, an outer tube having an end splined to the inner tube thereby defining an engagement area between the inner tube and the outer tube. The propshaft assembly also includes at least one stiffening ring disposed around the outer tube. At least a portion of the stiffening ring is in contact with the outer tube. ## Claims ### Claim 1 A propshaft assembly, comprising: a propshaft inner tube; a propshaft outer tube having an outer surface, an inner surface, and an end, the end splined to the inner tube thereby defining an engagement area between the inner tube and the outer tube; a first stiffening ring, wherein the first stiffening ring maintains the outer surface of the propshaft outer tube and reduces radial expansion of the propshaft outer tube, the first stiffening ring including a ring inner surface and a ring outer surface, the first stiffening ring is disposed around the propshaft outer tube, wherein at least a portion of the ring inner surface of the first stiffening ring is in direct contact with the propshaft outer tube, and at least a portion of the first stiffening ring inner surface generally circumferentially follows a contour of the propshaft outer tube outer surface; and a second stiffening ring disposed around the propshaft outer tube outer surface and axially spaced at a predetermined distance from the first stiffening ring for reducing radial expansion of the propshaft outer tube. ### Claim 2 (depends on 1) The propshaft assembly according to claim 1, wherein an outer surface of the propshaft outer tube includes a smooth portion. ### Claim 3 (depends on 1) The propshaft assembly according to claim 1, wherein at least one of the first stiffening ring and the second stiffening ring further comprises a seal portion. ### Claim 4 (depends on 3) The propshaft assembly according to claim 3, wherein the seal portion is disposed about the engagement area and is positioned against the end of the outer tube. ### Claim 5 (depends on 1) The propshaft assembly according to claim 1, wherein the propshaft outer tube and the propshaft inner tube are telescopingly arranged. ### Claim 6 (depends on 1) The propshaft assembly according to claim 1, wherein the stiffening ring is disposed about the engagement area and a portion of the stiffening ring extends beyond the end of the outer tube. ### Claim 7 (depends on 1) The propshaft assembly according to claim 1, wherein the inner tube and the outer tube have an interference fit. ### Claim 8 A propshaft assembly, comprising: a propshaft inner tube including a plurality of axially extending splines; a propshaft outer tube splined to the propshaft inner tube to define an engagement area, the propshaft outer tube including an outer surface and an inner surface; and a stiffening ring disposed around and in direct contact with the propshaft outer tube and having a stiffening portion, the propshaft outer tube outer surface and the propshaft outer tube inner surface having a corresponding contour within at least a portion of the stiffening ring, where the stiffening ring is constructed from a metal based material, and wherein the stiffening ring maintains a propshaft outer tube diameter and reduces radial expansion of the propshaft outer tube within at least a portion of the engagement area. ### Claim 9 (depends on 8) The propshaft assembly according to claim 8, wherein an outer surface of the propshaft outer tube has an indentation portion. ### Claim 10 (depends on 9) The propshaft assembly according to claim 9, wherein the stiffening ring is in contact with at least a portion of the indentation portion. ### Claim 11 (depends on 8) The propshaft assembly according to claim 8, wherein an end of the propshaft outer tube is splined to an end of the propshaft inner tube at the engagement area. ### Claim 12 (depends on 11) The propshaft assembly according to claim 11, wherein the seal portion is positioned against the end of the outer tube. ### Claim 13 (depends on 11) The propshaft assembly according to claim 11, wherein a portion of the stiffening ring extends beyond the end of the outer tube. ### Claim 14 (depends on 8) The propshaft assembly according to claim 8, wherein an outer surface of the propshaft outer tube includes a smooth portion. ### Claim 15 (depends on 14) The propshaft assembly according to claim 14, wherein the stiffening ring is in contact with at least a portion of the smooth portion. ### Claim 16 (depends on 1) The propshaft assembly according to claim 1, wherein the stiffening ring and the propshaft outer tube include an interference fit. ### Claim 17 (depends on 8) The propshaft assembly according to claim 8, further comprising a seal portion disposed around the propshaft outer tube. ### Claim 18 (depends on 8) The propshaft assembly according to claim 8, wherein at least a portion of the stiffening ring is fixedly attached to the outer surface of the propshaft outer tube. ### Claim 19 (depends on 18) The propshaft assembly according to claim 18, wherein the stiffening ring is attached by one of a weld, crimp, and a press fit.