# US 10,766,549 B2 · Lift axle drag reduction system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,766,549 B2 - Document ID: US10766549B2 - Status: Granted - Kind: B2 - Application number: 16/657,647 - Filed: 2019-10-18 - Published: 2020-04-16 - Granted: 2020-09-08 - Earliest claimed: 2017-05-05 - Assignees: PACCAR Inc - Applicants: PACCAR Inc - Inventors: Jeffrey P. Smith - Web page: https://patentgrep.com/patent/US10766549B2 ## CPC - B62D 61/12: with variable number of ground engaging wheels, e.g. with some wheels arranged higher than others, or with retractable wheels (for manoeuvring purposes only B60S) - B60G 17/0155: {pneumatic unit} - B60G 17/016: characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input {(B60G17/017 takes precedence)} - B60G 2204/4702: pneumatically - B60G 2204/62: Adjustable continuously, e.g. during driving - B60G 2300/0262: Multi-axle trucks - B60G 2400/204: Vehicle speed - B60G 2400/39: Brake pedal position - 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) - B60G: VEHICLE SUSPENSION ARRANGEMENTS (air-cushion vehicles B60V; {cycle suspensions B62K25/00}) ## Abstract A disclosed lift axle is suitable for a vehicle that has a first wheel for supporting the vehicle on a road surface. The lift axle system includes a lift mechanism that is coupled to the vehicle and is configured to reciprocate an axle between a stowed position and deployed position. The lift axle system further includes a second wheel coupled to the axle. The second wheel engages the road surface when the lift mechanism is in the deployed position, and the second wheel is disengaged from the road surface when the lift mechanism is in the stowed position. The second wheel has a lower rolling resistance than the first wheel. ## Claims ### Claim 1 A lift axle system for a vehicle having a first axle, a first wheel, and a tire for supporting the vehicle on a road surface, the lift axle system comprising: (a) a lift mechanism coupled to the vehicle, the lift mechanism being positioned adjacent to the first axle and configured to reciprocate a second axle between a stowed position and a deployed position; (b) a second wheel coupled to the second axle, the second wheel comprising a road-engaging element for engaging the road surface when the lift mechanism is in the deployed position, the road-engaging element being disengaged from the road surface when the lift mechanism is in the stowed position, and (c) a controller configured to cause the lift mechanism to selectively move the second axle between the deployed position and the stowed position, wherein the controller is configured to cause the lift mechanism to move the second axle from the deployed position to the stowed position based on receipt of a service brake signal indicative of a service brake engaged condition, and wherein the road-engaging element has a lower rolling resistance than the tire of the first wheel. ### Claim 2 (depends on 1) The lift axle system of claim 1, wherein the tire is filled with a compressed gas. ### Claim 3 (depends on 1) The lift axle system of claim 1, wherein the lift mechanism comprises a beam rotatably coupled to the vehicle, one end of the beam supporting the second axle. ### Claim 4 (depends on 3) The lift axle system of claim 3, wherein the lift mechanism further comprises an actuator operably coupled to the beam, the actuator selectively rotating the beam between a first position and a second position, wherein the lift mechanism is in the stowed position when the beam is in the first position, and the lift mechanism is in the deployed position when the beam is in the second position. ### Claim 5 (depends on 4) The lift axle system of claim 4, wherein the road-engaging element comprises a solid wear ring. ### Claim 6 (depends on 4) The lift axle system of claim 4, wherein the actuator is one of an electric actuator and a hydraulic actuator. ### Claim 7 (depends on 1) The lift axle system of claim 1, further comprising a vehicle speed sensor operatively coupled to the controller, wherein the controller is configured to cause the lift mechanism to move the second axle from the stowed position to the deployed position based on receipt of a vehicle speed signal indicative of a condition that the vehicle speed has exceeded a predetermined threshold speed. ### Claim 8 (depends on 1) The lift axle system of claim 1, further comprising a service brake sensor operatively coupled to the controller and configured to generate the service brake signal. ### Claim 9 (depends on 1) The lift axle system of claim 1, further comprising an operator input device operatively coupled to the controller, wherein the controller is programmed to stow and to deploy the lift mechanism in response to operator input from the operator input device. ### Claim 10 A lift axle system for a vehicle having a first axle, a first wheel, and a tire for supporting the vehicle on a road surface, the lift axle system comprising: (a) a beam positioned adjacent to the first axle and rotatably coupled to the vehicle; (b) a second axle coupled to the beam; (c) an actuator operably coupled to the beam to selectively rotate the beam between a stowed position and a deployed position; (d) a second wheel coupled to the second axle, the second wheel comprising a road-engaging element for engaging the road surface when the beam is in the deployed position, the road-engaging element being disengaged from the road surface when the beam is in the stowed position; and (e) a controller configured to cause the actuator to selectively rotate the beam between the stowed position and the deployed position, wherein the controller is configured to cause the actuator to move the beam from the deployed position to the stowed position based on receipt of a vehicle speed signal indicative of a condition that the vehicle speed has fallen below a predetermined threshold speed, and wherein the road-engaging element has a lower rolling resistance than the tire of the first wheel. ### Claim 11 (depends on 10) The lift axle system of claim 10, wherein the actuator is a first air spring engaging a first end of the beam to bias the beam toward the stowed position. ### Claim 12 (depends on 11) The lift axle system of claim 11, further comprising a second air spring engaging a second end of the beam to bias the beam toward the deployed position. ### Claim 13 (depends on 10) The lift axle system of claim 10, the road-engaging element is a solid wear ring. ### Claim 14 (depends on 10) The lift axle system of claim 10, wherein the controller is configured to cause the actuator to move the beam from the stowed position to the deployed position based on receipt of a vehicle speed signal indicative of a condition that the vehicle speed has exceeded a predetermined threshold speed. ### Claim 15 (depends on 10) The lift axle system of claim 10, further comprising a service brake sensor operatively coupled to the controller, wherein the controller is configured to cause the actuator to move the beam from the deployed position to the stowed position based on receipt of a service brake signal indicative of a service brake engaged condition. ### Claim 16 (depends on 10) The lift axle system of claim 10, further comprising an operator input device operatively coupled to the controller, wherein the controller is programmed to stow and to deploy the beam in response to operator input from the operator input device. ### Claim 17 (depends on 7) The lift axle system of claim 7, wherein the controller is further configured to cause the lift mechanism to move the second axle from the deployed position to the stowed position based on receipt of a vehicle speed signal indicative of a condition that the vehicle speed has fallen below a predetermined threshold speed. ### Claim 18 (depends on 17) The lift axle system of claim 17, wherein the predetermined threshold speed is 45 mph. ### Claim 19 A method for controlling a lift axle system for a vehicle having a first axle, a first wheel, and a tire for supporting the vehicle on a road surface, the lift axle system having a lift mechanism positioned adjacent to the first axle, a second wheel coupled to the second axle and comprising a road-engaging element for engagement with the road surface, and a controller, the method comprising: receiving, by the controller, a service brake signal indicative of a service brake engaged condition; and based on receipt of the service brake signal by the controller, causing the lift mechanism to move the second axle from a deployed position, wherein the road-engaging element of the second wheel engages the road surface, to a stowed position, wherein the road-engaging element disengages from the road surface.