Controller and method for controlling a lift axle and air suspension on a trailer
AssigneeBendix Commercial Vehicle Systems LLC
InventorJoseph M. Macnamara
Life of this patent
Estimating the term…
Abstract
A trailer having a liftable first axle and an air suspended second axle includes a controller, a first valve coupled to the first axle and a second valve coupled to the second axle. The controller receives an air suspension exhaust request signal and a pressure signal from an air suspension bellows coupled to the second axle. The controller transmits an air suspension control signal to the second valve in response to the air suspension exhaust request signal and transmits a lift axle control signal to the first valve to lower the first axle in response to the pressure signal being less than a predetermined pressure value.
Claims25
A trailer controller comprising:
- an air suspension bellows signal input for receiving a signal indicative of a pressure value in an air suspension bellows;
- a lift axle control output for transmitting a lift axle control signal;
- and
- a processor having control logic, the control logic capable of:
- receiving the air suspension bellows signal;
- transmitting the lift axle control signal to lower the lift axle in response to the pressure value in the air suspension bellows being less than a predetermined pressure value.
A system for controlling a lift axle and an air suspended axle on a trailer comprising:
- a manual switch to transmit a signal indicative of a driver request to exhaust suspension pressure;
- a pressure sensing device for transmitting a signal indicative of a pressure value in an air suspension bellows coupled to an air suspended axle;
- at least one wheel speed sensor for determining the speed of the trailer;
- a first electropneumatic valve for controlling a lift axle;
- a second electropneumatic valve for controlling a suspension pressure for the air suspended axle;
- and
- a controller having control logic, the control logic capable of:
- transmitting a lift axle control signal to the first electropneumatic valve to raise the lift axle;
- receiving the air suspension signal indicative of a request to exhaust suspension pressure in the air suspended axle;
- receiving the speed signal indicative of the speed of the trailer;
- transmitting an air suspension control signal to exhaust pressure in the air suspension bellows in response to signal indicative of a driver request to exhaust suspension pressure and the speed being less than a predetermined speed;
- receiving the signal indicative of the pressure value in the air suspension bellows;
- and
- transmitting a lift axle control signal to lower the lift axle in response the pressure value being less than a predetermined pressure value.
A method of controlling a liftable first axle and an air suspended second axle on a trailer comprising:
- receiving a signal indicative of a request to exhaust suspension pressure on an air suspended second axle;
- receiving a signal indicative of a pressure value in an air suspension bellows coupled to the air suspended second axle;
- and
- transmitting a control signal to lower a liftable first axle in response to the pressure value in the air suspension bellows being less than a predetermined pressure value.
An apparatus for a trailer having a liftable first axle and an air suspended second axle comprising:
- a controller, the controller capable of:
- receiving an air suspension exhaust request signal;
- receiving a pressure signal from an associated air suspension bellows coupled to an associated air suspended second axle;
- transmitting a lift axle signal to control an associated liftable first axle;
- and
- transmitting an air suspension control signal to control the associated air suspended second axle;
- a first valve, coupled to the associated liftable first axle, for receiving the lift axle signal;
- and
- a second valve, coupled to the associated air suspended second axle, for receiving the air suspension control signal;
- wherein the controller transmits the air suspension signal to the second valve in response to the air suspension exhaust request signal and transmits the lift axle signal to the first valve to lower the associated liftable first axle in response to the pressure signal being less than a predetermined pressure value.
A trailer controller for controlling a first axle and a second axle on a trailer comprising:
- an air suspension request input for receiving a signal indicative of a request to exhaust suspension air pressure in a suspension air bellows on a second axle;
- an air suspension bellows signal input for receiving a pressure signal indicative of a pressure value in the suspension air bellows;
- at least one speed input for receiving a signal indicative of a speed of a trailer;
- a first control output for transmitting a lift axle control signal to a first valve coupled to the suspension air bellows;
- a second control output for transmitting an air suspension control signal to control the pressure in the suspension air bellows;
- and
- a processor having control logic, the control logic capable of:
- transmitting the lift axle control signal to the first valve to raise the first axle;
- receiving the air suspension signal indicative of a request to exhaust suspension pressure;
- receiving the speed signal indicative of the speed of the trailer;
- transmitting the air suspension control signal to the second output to exhaust pressure in the suspension air bellows in response to the air suspension input signal indicative of a request to exhaust suspension pressure and the speed being less than a predetermined speed;
- receiving the air suspension bellows input signal indicative of the pressure value in the air suspension bellows;
- transmitting the lift axle control signal to lower the first axle in response to the pressure value being less than a predetermined pressure value.
An apparatus for a trailer having a liftable first axle and an air suspended second axle comprising:
- means for receiving a pressure value of an air suspension bellows on the air suspended second axle of a trailer;
- and
- means for lowering the liftable first axle;
- wherein the liftable first axle of the trailer is lowered in prior to substantial exhaustion of the air suspension bellows.
Dependencies are inferred from the claim text.