# US 2017/0288490 A1 · Breather structure of automotive motor drive unit and in-wheel motor drive unit including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0288490 A1 - Document ID: US20170288490A1 - Status: Published application - Kind: A1 - Application number: 15/503,750 - Filed: 2015-08-10 - Published: 2017-10-05 - Earliest claimed: 2014-08-20 - Assignees: Ntn Corporation - Applicants: Ntn Corporation - Inventors: Shiro TAMURA; Takanori ISHIKAWA; Shinya TAIKOU - Web page: https://patentgrep.com/patent/US20170288490A1 ## CPC - H02K 5/04: Casings or enclosures characterised by the shape, form or construction thereof - F16H 57/027: characterised by means for venting gearboxes, e.g. air breathers - H02K 5/203: {specially adapted for liquids, e.g. cooling jackets} - H02K 5/22: Auxiliary parts of casings not covered by groups H02K5/06-H02K5/20, e.g. shaped to form connection boxes or terminal boxes - H02K 9/02: by ambient air flowing through the machine - H02K 2205/09: Machines characterised by drain passages or by venting, breathing or pressure compensating means - Y02T 10/64: Electric machine technologies in electromobility - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - F16H: GEARING - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An automotive motor drive unit includes a breather passage (Q) provided in casings (21a, 21r, 22a, 22r) that form an outer shape of the automotive motor drive unit; an entrance port (48m) that is provided at an inlet side of the breather passage and that connects with an internal space (L) defined by the casings; an exit port (67) that is provided at an outlet side of the breather passage and that connects with a space outside the casings; and obstacles (24, 25, 26) standing to form an inner wall of the breather passage and preventing lubrication oil in the internal space from proceeding straight ahead via the entrance port toward the exit port. ## Claims ### Claim 1 A breather structure of an automotive motor drive unit, comprising: a breather passage provided in a casing that forms an outer shape of the automotive motor drive unit; an entrance port provided at an inlet side of the breather passage, the entrance port connecting with an internal space defined by the casing; an exit port provided at an outlet side of the breather passage, the exit port connecting with a space outside the casing; and an obstacle standing to form an inner wall of the breather passage, the obstacle preventing lubrication oil in the internal space from proceeding straight ahead via the entrance port toward the exit port. ### Claim 2 (depends on 1) The breather structure of the automotive motor drive unit according to claim 1, wherein the breather passage includes a pair of a first side surface and a second side surface facing each other, the first and second side surfaces extending from the inlet side through the outlet side, and the obstacle includes: a first barrier standing on the first side surface, the first barrier forming a gap between the first barrier and the second side surface; and a second barrier standing on the second side surface at a position closer to the outlet side than the first barrier, the second barrier forming a gap between the second barrier and the first side surface. ### Claim 3 (depends on 2) The breather structure of the automotive motor drive unit according to claim 2, wherein at least three of the first and second barriers are alternately disposed along the breather passage. ### Claim 4 (depends on 2) The breather structure of the automotive motor drive unit according to claim 2, wherein the breather passage further includes an undersurface connected to the first side surface and the second side surface, the undersurface sloping down from the outlet side to the inlet side of the breather passage. ### Claim 5 (depends on 2) The breather structure of the automotive motor drive unit according to claim 2, wherein the exit port is formed on the second side surface. ### Claim 6 (depends on 2) The breather structure of the automotive motor drive unit according to claim 2, wherein the casing includes a first casing and a second casing being joined to each other, the first side surface and the first barrier are integrated with the first casing, and the second side surface and the second barrier are integrated with the second casing. ### Claim 7 (depends on 1) The breather structure of the automotive motor drive unit according to claim 1, wherein the breather passage is disposed in a terminal box that leads a power cable into the automotive motor drive unit. ### Claim 8 (depends on 1) An in-wheel motor drive unit comprising: a motor portion; a wheel hub bearing portion; a speed reduction portion configured to decelerate rotation at the motor portion and output the rotation to the wheel hub bearing portion; and the breather structure of the automotive motor drive unit according to claim 1, the breather structure being provided in at least one of a casing for the motor portion and a casing for the speed reduction portion.