# US 11,994,188 B2 · Viscous torsional-vibration damper and method for producing a viscous torsional-vibration damper > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,188 B2 - Document ID: US11994188B2 - Status: Granted - Kind: B2 - Application number: 17/288,295 - Filed: 2019-10-21 - Published: 2021-12-09 - Granted: 2024-05-28 - Earliest claimed: 2018-10-24 - Assignees: Hasse & Wrede GmbH - Applicants: Hasse & Wrede GmbH - Inventors: Nobert Reinsperger; Michael Steidl - Web page: https://patentgrep.com/patent/US11994188B2 ## CPC - F16F 15/173: provided within a closed housing {(F16F15/36 takes precedence)} - F16F 2222/08: Inertia - F16F 2222/12: Fluid damping - F16F 2224/0208: Alloys - F16F 2226/048: Welding - F16F 2232/02: Rotary - F16F 2234/02: cylindrical - F16F 2236/08: Torsion - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION ## Abstract A viscous torsional-vibration damper has a damper housing with an axis of rotation, an annular working chamber filled with a damping medium, an inertia ring arranged inside the working chamber, and a cover for media-tight closure of the working chamber. The cover is connected to the damper housing peripherally on one side by a sequence of a butt seam and an overlap seam. ## Claims ### Claim 1 A viscous torsional-vibration damper, comprising: a damper housing having an axis of rotation and an annular working chamber filled with a damping medium; an inertia ring arranged inside the working chamber; and a cover for medium-tight closure of the working chamber, wherein the cover is connected to the damper housing circumferentially at least on one side by a sequence of a butt seam and a lap seam, and the lap seam is arranged offset in a radial direction by 1-7 mm relative to the butt seam, wherein the viscous torsional-vibration damper has a first wall with an inner lateral surface and a second wall with an outer lateral surface, the working chamber is arranged between the inner and outer lateral surfaces and thereby also between the first and second walls, and the sequence of a lap seam and a butt seam is arranged in a radially inner edge region of the cover, wherein both weld seams connect the cover to the first wall comprising the inner lateral surface. ### Claim 2 A viscous torsional-vibration damper, comprising: a damper housing having an axis of rotation and an annular working chamber filled with a damping medium; an inertia ring arranged inside the working chamber; and a cover for medium-tight closure of the working chamber, wherein the cover is connected to the damper housing circumferentially at least on one side by a sequence of a butt seam and a lap seam, and the lap seam is arranged offset in a radial direction by 1-7 mm relative to the butt seam, wherein the viscous torsional-vibration damper has a first wall with an inner lateral surface and a second wall with an outer lateral surface, the working chamber is arranged between the inner and outer lateral surfaces and thereby also between the first and second walls, and the sequence of a lap seam and a butt seam is arranged in a radially outer edge region of the cover, wherein both weld seams connect the cover to the first wall comprising the outer lateral surface. ### Claim 3 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the cover is an annular plate with a radially outer and a radially inner edge region, and the cover is connected circumferentially to the damper housing in the outer edge region and in the inner edge region in each case by a sequence of a butt seam and a lap seam. ### Claim 4 (depends on 2) The viscous torsional-vibration damper as claimed in claim 2, wherein the cover is an annular plate with a radially outer and a radially inner edge region, and the cover is connected circumferentially to the damper housing in the outer edge region and in the inner edge region in each case by a sequence of a butt seam and a lap seam. ### Claim 5 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the damper housing has a stepped cover receptacle, the cover is of annular design with an inner surface in contact with the damping medium and an opposite outer surface without contact with the damping medium, the cover has a first and second circumferential end surface on edges of the inner and outer surface, wherein the first and second end surfaces are connected to the cover receptacle in each case by a butt seam. ### Claim 6 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the damper housing is connected to the cover mounted on top, the cover is of annular design with an inner surface in contact with the damping medium and an opposite outer surface without contact with the damping medium, and the cover is welded to the damper housing in edge regions of the inner and outer surfaces in each case by a lap seam. ### Claim 7 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the butt seam is designed as a non-welded-through weld seam, forming less than 80% of a cover height of the cover. ### Claim 8 (depends on 7) The viscous torsional-vibration damper as claimed in claim 7, wherein the lap seam extends as a welded-through weld seam over an entire cover height of the cover and extends partially into the damper housing, with a depth of at least 30% of the cover height into the damper housing. ### Claim 9 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the lap seam extends as a welded-through weld seam over an entire cover height of the cover and extends partially into the damper housing, with a depth of at least 30% of the cover height into the damper housing. ### Claim 10 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein a radial distance between the position of the lap seam on a supporting surface of a cover receptacle of the damper housing and the transition of the supporting surface to the working chamber amounts to at least 50% of the cover height. ### Claim 11 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein a radial distance between the position of the lap seam on a supporting surface of a cover receptacle of the damper housing and the transition of the supporting surface to the working chamber amounts to at least 70% of the cover height. ### Claim 12 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein a radial distance between the position of the lap seam on a supporting surface of a cover receptacle of the damper housing and the transition of the supporting surface to the working chamber amounts to at least 75% to 250% of the cover height. ### Claim 13 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the damper housing is made of cast metal. ### Claim 14 (depends on 1) The viscous torsional-vibration damper as claimed in claim 1, wherein the damper housing is made of grey cast iron. ### Claim 15 A method for producing a viscous torsional-vibration damper, the method comprising: a) providing a damper body comprising an annular working chamber for receiving an inertia ring via a chamber opening; b) inserting the inertia ring into the working chamber of the damping body; c) closing the working chamber of the damping body with a cover by at least one medium-tight circumferential welded joint; and d) filling the working chamber with a damping medium, wherein the welded joint is, at least in an edge region of the cover, carried out by a sequence of a butt seam and a lap seam, and the lap seam is arranged offset in a radial direction by 1-7 mm relative to the butt seam, the viscous torsional-vibration damper has a first wall with an inner lateral surface and a second wall with an outer lateral surface, the working chamber is arranged between the inner and outer lateral surfaces and thereby also between the first and second walls, and the sequence of a lap seam and a butt seam is arranged in a radially inner edge region of the cover, wherein both weld seams connect the cover to the first wall comprising the inner lateral surface. ### Claim 16 (depends on 15) The method as claimed in claim 15, wherein the butt seam and the lap seam are produced by laser and/or electron beam welding.