# US 7,407,458 B2 · In-line drivetrain and four wheel drive work machine using same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,458 B2 - Document ID: US7407458B2 - Status: Granted - Kind: B2 - Application number: 11/258,961 - Filed: 2005-10-26 - Published: 2007-04-26 - Granted: 2008-08-05 - Earliest claimed: 2005-10-26 - Assignees: Caterpillar Inc. - Inventors: Brian Hoff - Web page: https://patentgrep.com/patent/US7407458B2 ## CPC - B60K 17/34: for driving both front and rear wheels, e.g. four wheel drive vehicles - B60K 17/16: of differential gearing - B62D 53/026: {With all wheels powered} - 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) - B60Y 2200/415: Wheel loaders - 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 - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY ## Abstract A four wheel drive articulated mine loader is powered by a fuel cell and propelled by a single electric motor. The drivetrain has the first axle, second axle, and motor arranged in series on the work machine chassis. Torque is carried from the electric motor to the back differential via a pinion meshed with the ring gear of the back differential. A second pinion oriented in an opposite direction away from the ring gear is coupled to a drive shaft to transfer torque from the ring gear to the differential of the front axle. Thus, the ring gear of the back differential acts both to receive torque from the motor and to transfer torque to the forward axle. The in-line drive configuration includes a single electric motor and a single reduction gear to power the four wheel drive mine loader. ## Claims ### Claim 1 A four wheel drive vehicle, comprising: a chassis; a motor connected to the chassis; a first axle and a first differential coupled to the chassis; a second axle and a second differential coupled to the chassis; the chassis being completely supported by wheels attached to the first and second axles; a first drive shaft coupled between the first differential and the second differential; a second drive shaft coupled between the motor and the first differential, on a side of the first differential opposite from the first drive shaft; the motor is an electric motor; and a reduction gear coupling the second drive shaft to the electric motor. ### Claim 2 (depends on 1) The vehicle of claim 1 wherein the motor has an axis of rotation that intersects the first axle; the chassis has a front portion connected to a back portion; and the motor is mounted on the back portion. ### Claim 3 (depends on 1) The vehicle of claim 1 wherein the first drive shaft and the second drive shaft include collinear axes of rotation. ### Claim 4 (depends on 1) The vehicle of claim 1 wherein the first drive shaft includes a first pinion meshed with a ring gear of the first differential; and the second drive shaft includes a second pinion meshed with the ring gear. ### Claim 5 (depends on 4) The vehicle of claim 4 wherein the first and second pinions are identical. ### Claim 6 (depends on 4) The vehicle of claim 4 wherein the first and second pinions are meshed with the ring gear on opposite sides of the first axle. ### Claim 7 (depends on 6) The vehicle of claim 6 wherein the motor has an axis of rotation that intersects the first axle. ### Claim 8 (depends on 7) The vehicle of claim 7 wherein the first and second pinions have collinear axes of rotation. ### Claim 9 (depends on 8) The vehicle of claim 8 wherein the axis of rotation of the motor is collinear with the axes of rotation of the first and second pinions. ### Claim 10 (depends on 4) The vehicle of claim 4 wherein the first axle is a back axle; the second axle is a front axle; the electric motor is aft of the back axle; and a movable bucket connected to the chassis forward of the front axle. ### Claim 11 (depends on 10) The vehicle of claim 10 wherein the chassis includes a front portion joined to a back portion at an articulation. ### Claim 12 A drivetrain comprising: a first differential including a ring gear, and having a first side and a second side opposite the first side, and including a first pinion meshed with the ring gear and having a first shaft extending toward the first side, and further including a second pinion meshed with the ring gear and having a second shaft extending toward the second side; a motor operably coupled to one of the first and second pinions; a driven element operably coupled to an other one of the first and second pinions; the motor, the first differential and the driven element being sequentially positioned from a back toward a front of the drivetrain; the motor is an electric motor; and a reduction gear coupled between the electric motor and the first pinion. ### Claim 13 (depends on 12) The drivetrain of claim 12 wherein the first and second pinions have collinear axes of rotation. ### Claim 14 (depends on 13) The drivetrain of claim 13 wherein the driven element includes a second differential operably coupled to the second pinion via a drive shaft; and an articulation positioned between the first differential and the second differential for articulating the first differential relative to the second differential. ### Claim 15 (depends on 14) The drivetrain of claim 14 wherein the electric motor has an axis of rotation that is collinear with the axis of rotation of the first pinion. ### Claim 16 A method of operating a four wheel drive vehicle, comprising the steps of: completely supporting a chassis of the four wheel drive vehicle on wheels attached to first and second axles; torquing a ring gear of a first differential coupled to the first axle with a motor; transferring torque from the first differential to a second differential coupled to the second axle via a drive shaft coupled to the ring gear; arranging the motor, the first differential and the second differential in series on the vehicle from a back toward a front of the vehicle; articulating a front portion of a chassis relative to a back portion of the chassis via an articulation positioned between the first differential and the second differential; and electrically powering the motor with at least one of a fuel cell, a battery, a generator and a microturbine.