# US 10,865,873 B2 · Motor unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,865,873 B2 - Document ID: US10865873B2 - Status: Granted - Kind: B2 - Application number: 16/323,932 - Filed: 2017-08-07 - Published: 2019-06-20 - Granted: 2020-12-15 - Earliest claimed: 2016-08-09 - Assignees: Nidec Corporation - Applicants: Nidec Corporation - Inventors: Yuki Ishikawa; Yasuo Yamaguchi; Takayuki Migita - Web page: https://patentgrep.com/patent/US10865873B2 ## CPC - F16H 57/0476: {Electric machines and gearing, i.e. joint lubrication or cooling or heating thereof} - F16H 57/021: Shaft support structures, e.g. partition walls, bearing eyes, casing walls or covers with bearings - F16H 57/043: {within rotary parts, e.g. axial channels or radial openings in shafts} - H02K 7/083: {radially supporting the rotary shaft at both ends of the rotor (H02K7/086, H02K7/09 take precedence)} - H02K 7/116: with gears - H02K 9/19: for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil - B60K 6/26: characterised by the motors or the generators - B60K 6/36: characterised by the transmission gearings - B60K 6/387: Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means - B60K 6/405: Housings - B60K 17/04: characterised by arrangement, location or kind of gearing - B60Y 2200/92: Hybrid vehicles - B60Y 2306/05: Cooling - B60Y 2400/60: Electric Machines, e.g. motors or generators - B60Y 2400/70: Gearings - B60Y 2410/10: Housings - F16H 2057/02034: {Gearboxes combined or connected with electric machines} - F16H: GEARING - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY ## Abstract A motor unit includes a motor including a shaft to rotate about a motor axis, and a stator, a reduction gear, and a housing. The shaft includes a first shaft portion, a connecting shaft portion, and a second shaft portion arranged coaxially with one another, and a separating mechanism between the connecting shaft portion and the second shaft portion. The first shaft portion includes a first end portion. The connecting shaft portion includes a second end portion coupled to the first end portion, a third end portion located on a side opposite to the second end portion, and a connection flange portion extending radially outward. The second shaft portion includes a fourth end portion. The separating mechanism selectively separates the connection flange portion and the fourth end portion from each other. ## Claims ### Claim 1 A motor unit comprising: a motor including a shaft to rotate about a motor axis extending in a horizontal direction and a stator surrounding the shaft from radially outside; a reduction gear connected to the shaft; and a housing including a housing space to house the motor and the reduction gear; wherein the housing space includes: a motor chamber to house the motor; and a gear chamber to house the reduction gear; the housing includes a partition to divide the motor chamber and the gear chamber; the shaft includes: a first shaft portion, a connecting shaft portion, and a second shaft portion arranged coaxially with one another; and a separating mechanism between the connecting shaft portion and the second shaft portion; the first shaft portion includes a first end portion extending through an insert hole defined in the partition from a side on which the motor chamber lies; the connecting shaft portion includes: a second end portion coupled to the first end portion; a third end portion on a side opposite to the second end portion; and a connection flange portion extending radially outward at the third end portion; the second shaft portion includes a fourth end portion on a side closer to the third end portion of the connecting shaft portion; the separating mechanism selectively separates the connection flange portion and the fourth end portion from each other; a first bearing is in a radial gap between the third end portion and the fourth end portion; the second shaft portion includes a fifth end portion on a side opposed to the fourth end portion, the fifth end portion being rotatably supported by a second bearing which is held by the housing; and the second shaft portion is directly supported by the first bearing and the second bearing at opposing ends of the second shaft portion in the horizontal direction. ### Claim 2 (depends on 1) The motor unit according to claim 1, wherein one of the third end portion and the fourth end portion includes a first recessed portion to house another one of the third end portion and the fourth end portion. ### Claim 3 (depends on 2) The motor unit according to claim 2, wherein the first bearing is a needle bearing including a plurality of columnar members with an annular shape. ### Claim 4 (depends on 2) The motor unit according to claim 2, wherein the first shaft portion, the connecting shaft portion, and the second shaft portion include hollow portions extending in an axial direction and to be in communication with one another; and the hollow portions are structured to allow an oil to cool an inside of the motor to be fed thereinto from a side on which the second shaft portion lies toward a side on which the first shaft portion lies. ### Claim 5 (depends on 1) The motor unit according to claim 1, wherein the first end portion includes a second recessed portion, an outer circumferential surface of the second end portion being fitted to the second recessed portion. ### Claim 6 (depends on 1) The motor unit according to claim 1, wherein the first end portion of the first shaft portion is supported by a third bearing in contact with and held by a surface of the partition facing the motor chamber. ### Claim 7 (depends on 1) The motor unit according to claim 1, wherein the connecting shaft portion is supported by a fourth bearing in contact with and held by a surface of the partition facing the gear chamber. ### Claim 8 (depends on 7) The motor unit according to claim 7, wherein the fourth bearing is a ball bearing; and the connecting shaft portion includes a shoulder surface facing toward the partition and in contact with an inner race of the fourth bearing. ### Claim 9 (depends on 1) The motor unit according to claim 1, wherein the first end portion of the first shaft portion is supported by a third bearing in contact with and held by a surface of the partition facing the motor chamber; the connecting shaft portion is supported by a fourth bearing in contact with and held by a surface of the partition facing onto the gear chamber; and the fourth bearing has an outside diameter greater than an outside diameter of the third bearing. ### Claim 10 (depends on 1) The motor unit according to claim 1, wherein the second shaft portion includes a first gear between the fourth end portion and the fifth end portion to transfer power to the reduction gear. ### Claim 11 (depends on 10) The motor unit according to claim 10, wherein the reduction gear includes a second gear connected to the first gear and a third gear rotatable in synchronism with the second gear; and the third gear and the separating mechanism axially overlap with each other.