# US 11,906,034 B2 · Drive apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,034 B2 - Document ID: US11906034B2 - Status: Granted - Kind: B2 - Application number: 17/942,178 - Filed: 2022-09-12 - Published: 2023-03-16 - Granted: 2024-02-20 - Earliest claimed: 2021-09-15 - Assignees: Nidec Corporation - Applicants: Nidec Corporation - Inventors: Shuhei Nakamatsu; Keisuke Aso; Ayumi Nakagawa - Web page: https://patentgrep.com/patent/US11906034B2 ## CPC - F16H 57/0424: {Lubricant guiding means in the wall of or integrated with the casing, e.g. grooves, channels, holes} - B60K 11/02: with liquid cooling - F16H 57/021: Shaft support structures, e.g. partition walls, bearing eyes, casing walls or covers with bearings - F16H 57/031: characterised by covers or lids for gearboxes - F16H 57/0417: {Heat exchangers adapted or integrated in the gearing} - F16H 57/0426: {Means for guiding lubricant into an axial channel of a shaft} - F16H 57/043: {within rotary parts, e.g. axial channels or radial openings in shafts} - F16H 57/0435: {Pressure control for supplying lubricant; Circuits or valves therefor} - F16H 57/0471: {Bearing} - F16H 57/0476: {Electric machines and gearing, i.e. joint lubrication or cooling or heating thereof} - F16H 57/0483: {Axle or inter-axle differentials} - B60K 1/00: Arrangement or mounting of electrical propulsion units (B60K7/00 takes precedence; arrangement or mounting of plural diverse prime-movers for mutual or common propulsion B60K6/00) - B60K 2001/001: {one motor mounted on a propulsion axle for rotating right and left wheels of this axle} - B60K 2001/006: {the electric motors} - B60Y 2306/03: Lubrication - F16H 57/045: {Lubricant storage reservoirs, e.g. reservoirs in addition to a gear sump for collecting lubricant in the upper part of a gear case} - F16H 57/0457: {Splash lubrication} - F16H 2057/02034: {Gearboxes combined or connected with electric machines} - F16H: GEARING - 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 In a drive apparatus, a ring gear of a differential device is rotatable about a third axis in a direction opposite to a counter gear of a deceleration device. The inner surface of the gear housing accommodating the deceleration device, the differential device, and the reservoir capable of storing a fluid includes first and second curved surfaces disposed in the +X direction with respect to the third and second axes, respectively. At least a part of the first curved surface faces the radially outer end portion of the ring gear in the radial direction and extends in the circumferential direction. At least a part of the second curved surface faces the radially outer end portion of the counter gear in the radial direction and extends in the circumferential direction. The position of the reservoir in the Y-axis direction overlaps the first curved surface and the second curved surface. ## Claims ### Claim 1 A drive apparatus, comprising: a motor portion having a motor shaft rotatable about a first axis extending in a first direction; a deceleration device connected to a portion of the motor shaft which is located on a first side in the first direction; a differential device connected to the deceleration device; a reservoir configured to store a fluid; and a gear housing configured to accommodate the deceleration device, the differential device, and the reservoir, wherein the deceleration device includes a counter gear rotatable about a second axis extending in the first direction, the differential device includes a ring gear rotatable in a direction opposite to the counter gear about a third axis extending in the first direction, the ring gear is disposed on a second side in the first direction with respect to the counter gear, the second side opposite the first side in the first direction, an inner surface of the gear housing includes: a first curved surface disposed on a first side in a second direction perpendicular to the first direction with respect to the third axis, a second curved surface disposed on the first side in the second direction with respect to the second axis, a first inner surface that is disposed on the first side in the first direction with respect to the ring gear, and overlaps the ring gear in the first direction, and a second inner surface that is disposed on the first side in the first direction with respect to the first inner surface and the counter gear, and overlaps the counter gear in the first direction, at least a part of the first curved surface extends in a circumferential direction so as to face a radially outer end portion of the ring gear in a radial direction, at least a part of the second curved surface extends in the circumferential direction while radially facing a radially outer end portion of the counter gear, a position of a first portion of the reservoir on the second side in the first direction overlaps the first curved surface, a position of a second portion of the reservoir on the first side in the first direction overlaps the second curved surface, a first end portion of the second curved surface which is located on the first side in the first direction is connected to the second inner surface, a second end portion of the second curved surface which is located on the second side in the first direction is connected to the first inner surface, the gear housing includes a gear lid portion disposed on the first side in the first direction with respect to the counter gear, and the first curved surface, the second curved surface, the first inner surface, and the second inner surface are formed in the gear lid portion. ### Claim 2 (depends on 1) The drive apparatus according to claim 1, wherein the gear housing further includes a bearing holder configured to rotatably support a drive shaft connected to the differential device via a bearing and a supply flow path portion connecting an inside of the reservoir and an inside of the bearing holder. ### Claim 3 (depends on 2) The drive apparatus according to claim 2, wherein the supply flow path portion is disposed on at least one of: the first side in the first direction with respect to the second end portion of the second curved surface, and the second side in the first direction with respect to the first end portion of the second curved surface. ### Claim 4 (depends on 2) The drive apparatus according to claim 2, wherein the supply flow path portion is disposed on at least one of: the first side in the first direction with respect to the counter gear, and the second side in the first direction with respect to the counter gear. ### Claim 5 (depends on 2) The drive apparatus according to claim 2, wherein the gear lid portion further includes a second gear bearing holder and a second intermediate bearing holder, the supply flow path portion includes a fourth supply flow path portion, and a fifth supply flow path portion, the fourth supply flow path portion connects the inside of the reservoir and the second gear bearing holder, and the fifth supply flow path portion connects the inside of the reservoir and the second intermediate bearing holder. ### Claim 6 (depends on 1) The drive apparatus according to claim 1, wherein the reservoir is disposed on a first side in a third direction with respect to the second axis, the third direction is perpendicular to the first direction and the second direction, the second curved surface includes: a first surface extending in the circumferential direction along the radially outer end portion of the counter gear, and a second surface extending from a first end portion of the first surface which is located on the first side in the third direction toward the first side in the third direction, and a third end portion of the second curved surface which is located on the first side in the third direction is disposed on the first side in the third direction with respect to the reservoir. ### Claim 7 (depends on 6) The drive apparatus according to claim 6, wherein the second surface includes a first concave surface that is concave toward the first side in the second direction. ### Claim 8 (depends on 6) The drive apparatus according to claim 6, wherein the gear lid portion expands in at least one of the second and third directions, and the second surface is disposed on the gear lid portion, expands in the first direction, and expands in the second direction. ### Claim 9 (depends on 6) The drive apparatus according to claim 6, wherein the second surface includes a second concave surface that is concave toward the first side in the third direction, and the second concave surface is disposed at the third end portion of the second curved surface. ### Claim 10 (depends on 1) The drive apparatus according to claim 1, wherein the gear housing further includes at least one of: a first guide portion extending from an end portion of the first curved surface toward the reservoir, and a second guide portion extending from an end portion of the second curved surface toward the reservoir. ### Claim 11 (depends on 10) The drive apparatus according to claim 10, wherein the gear housing includes the first guide portion and the second guide portion, and the second guide portion extends along the first guide portion when viewed from the first direction. ### Claim 12 (depends on 1) The drive apparatus according to claim 1, wherein the reservoir is disposed on a second side in the second direction with respect to the radially outer end portion of the counter gear on the first side in the second direction, the second side opposite the first side in the second direction. ### Claim 13 A drive apparatus, comprising: a motor portion having a motor shaft rotatable about a first axis extending in a first direction; a deceleration device connected to a portion of the motor shaft which is located on a first side in the first direction; a differential device connected to the deceleration device; a reservoir configured to store a fluid; and a gear housing configured to accommodate the deceleration device, the differential device, and the reservoir, wherein the deceleration device includes a counter gear rotatable about a second axis extending in the first direction, the differential device includes a ring gear rotatable in a direction opposite to the counter gear about a third axis extending in the first direction, an inner surface of the gear housing includes: a first curved surface disposed on a first side in a second direction perpendicular to the first direction with respect to the third axis, and a second curved surface disposed on the first side in the second direction with respect to the second axis, at least a part of the first curved surface extends in a circumferential direction so as to face a radially outer end portion of the ring gear in a radial direction, at least a part of the second curved surface extends in the circumferential direction while radially facing a radially outer end portion of the counter gear, a position of a first portion of the reservoir on a second side in the first direction overlaps the first curved surface, the second side opposite the first side in the first direction, a position of a second portion of the reservoir on the first side in the first direction overlaps the second curved surface, the first curved surface is offset in the first direction from the second curved surface, the reservoir is disposed on a first side in a third direction with respect to the second axis, the third direction is perpendicular to the first direction and the second direction, the second curved surface includes: a first surface extending in the circumferential direction along the radially outer end portion of the counter gear, and a second surface extending from a first end portion of the first surface which is located on the first side in the third direction toward the first side in the third direction, and a third end portion of the second curved surface which is located on the first side in the third direction is disposed on the first side in the third direction with respect to the reservoir.