Rotary Union Assembly For Use In Air Pressure Inflation Systems For Tractor Trailer Tires

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings said assembly comprising:

• a conduit support carried by an end of an axle and defining a channel extending axially therethrough;
• a tubular conduit having a rigid portion and a flexible portion, said flexible portion being axially aligned with and downstream of said rigid portion, said rigid portion extending axially through said conduit support and communicating with the interior of said axle whereby a sealed air flow conduit can be provided between said annular sealing member in said conduit support and said shaft member when said shaft member is out of axial alignment with said conduit supports
• a stationary shaft member having an air passageway extending axially therethrough and communicating with said tubular conduit;
• a housing attachable to a hub cap for rotation therewith, said housing defining a centrally disposed channel therein and being rotatably mounted on said stationary shaft member such that said air passageway in said shaft member communicates with said channel in said housing, where by airflow is directed from said axle through said tubular conduit and said stationary shaft member to said rotatable housing;
• and
• an air hose assembly communicating said centrally disposed channel in said rotatable housing with at least one of the vehicle tires.

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said assembly comprising:

• a spindle plug assembly adapted to be mounted in an end of an axle in a stationary disposition for communicating the source of pressurized air through the axle with said rotary union assembly, said spindle plug assembly defining a channel extending axially therethrough;
• an annular sealing member disposed in said spindle plug assembly about said channel therein;
• a tubular conduit having a rigid portion and a flexible portion, said flexible portion being axially aligned with and downstream of said rigid portion and said rigid portion being adapted to extend axially through said channel in said spindle plug assembly and communicate with the interior of said axle such that said sealing member engages said rigid portion of said tubular conduit and forms an airtight seal therewith;
• a stationary rigid shaft member having an air passageway extending axially therethrough for communicating with said tubular conduit;
• a housing attachable to the exterior of a hub cap for rotation therewith, said housing defining a centrally disposed channel therein and being rotatably mounted on said stationary shaft member such that said air passageway in said shaft member communicates with said channel in said housing, where by airflow is directed from said axle through said tubular conduit and said stationary shaft member to said rotatable housing;
• and
• an air hose assembly communicating said centrally disposed channel in said rotatable housing with at least one of the vehicle tires.

A housing assembly for a rotary union in an automatic tire inflation system for communicating the rotary union with a source of pressurized air and a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said housing assembly defining a central channel therein for containing the rotary union and being attachable to the hub cap for rotation therewith such that said central channel is communicable with the source of pressurized air through the axle, and wherein said housing assembly includes at least one pressure relief channel extending axially therethrough, said channel defining an upstream end communicating with the interior of said hub cap upon said housing being attached to the hub cap and a downstream end communicating with the atmosphere exteriorly of the hub cap, a valve member slidably mounted within said channel and moveable between an open position and a closed position and a spring member biasing said valve member to said closed position so as to prevent fluid flow therethrough, said spring member being responsive to a pressure build-up within the lubrication compartment so as to move said valve member to said open position upon said pressure build-up reaching a predetermined level whereby air in the lubrication compartment passes through said pressure relief channel to the atmosphere reducing the pressure build-up within the lubrication compartment.

The housing assembly for the rotary union in an automatic tire inflation system for communicating the rotary union with a source of pressurized air and a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said housing assembly defining a central channel therein for containing the rotary union and being attachable to the exterior of the hub cap for rotation therewith such that said central channel is communicable with the source of pressurized air through the axle, and wherein said housing assembly includes a pair of pressure relief channels extending axially therethrough, said channel defining an upstream end communicating with the interior of said hub cap upon said housing being attached to the hub cap and a downstream end communicating with the atmosphere exteriorly of the hub cap, a valve member slidably mounted within said channel and moveable between an open position and a closed position and a spring member biasing said valve member to said closed position so as to prevent fluid flow therethrough, said spring member being responsive to a pressure build-up within the lubrication compartment so as to move said valve member to said open position upon said pressure build-up reaching a predetermined level whereby air in the lubrication compartment passes through said pressure relief channel to the atmosphere reducing the pressure build-up within the lubrication compartment.

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle of a type having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said assembly comprising:

• a conduit support carried by an end of an axle and defining a channel extending axially therethrough;
• an annular sealing member disposed in said conduit support about said channel therein.
• a stationary tubular conduit defining an upstream end portion and a downstream end portion, said upstream end portion extending axially through said conduit support and communicating with the interior of said axle, said sealing member engaging said tubular conduit and forming an airtight seal within said conduit support about said tubular conduit;
• a housing attachable to the exterior of a hub cab for rotation therewith, said housing defining at least one air passageway extending therethrough and being rotatably mounted on said downstream end portion of said tubular conduit such that said tubular conduit communicates the interior of said axle with said air passageway in said housing, whereby air flow is directed from said axle through said stationary tubular conduit to said rotatable housing;
• and
• an air hose assembly communicating said air passageway in said rotatable housing with at least one of the vehicle tires, said air hose assembly comprising, an air hose, a first fitting carried by said housing and communicating with said air passageway therein, a first pressure actuated check valve disposed within said first fitting, a second fitting carried by a first end portion of said air hose, said second fitting being adapted to be coupled with said first fitting and hold said check valve in an open position such that air can pass therethrough into said air hose, a third fitting carried by a second end of said air hose, said third fitting being adapted to be coupled with the vehicle tire, and a second pressure actuated check valve carried by said third fitting for preventing air loss from the vehicle tire in the event of an air leak in said air hose.

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said assembly comprising:

• a conduit support carried by an end of an axle and defining a channel extending axially therethrough;
• a tubular conduit having a rigid portion and a flexible portion, said rigid portion extending axially through said conduit support and communicating with the interior of said axle;
• a stationary shaft member having an air passageway extending axially therethrough and communicating with said tubular conduit;
• a housing attachable to the exterior of a hub cap for rotation therewith, said housing defining a centrally disposed channel therein and being rotatably mounted on said stationary shaft member such that said air passageway in said shaft member communicates with said channel in said housing, whereby airflow is directed from said axle through said tubular conduit and said stationary shaft member to said rotatable housing;
• a rotary union comprising a rotary element and a stationary element, said rotary union being disposed in said central channel in said housing;
• and
• an air hose assembly communicating said centrally disposed channel in said rotatable housing with at least one of the vehicle tires.

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said assembly comprising:

• a conduit support carried by an end of an axle and defining a channel extending axially therethrough;
• a tubular conduit having a rigid portion and a flexible portion, said flexible portion being axially aligned with and downstream of said rigid portion and wherein said rigid portion extends axially through said conduit support and communicates with the interior of said axle;
• a housing attachable to the exterior of a hub cap for rotation therewith, said housing defining a centrally disposed channel therein for communicating with the source of pressurized air through said tubular conduit;
• a rotary union comprising a rotary element and a stationary element, said rotary union being disposed in said central channel in said housing;
• and
• an air hose assembly communicating said centrally disposed channel in said rotatable housing with at least one of the vehicle tires.

A rotary union assembly for use in an automatic tire inflation system for maintaining a desired pressure in a plurality of pneumatic tires mounted on the wheels of a vehicle having a source of pressurized air for fluid communication with the tires through the axles and a hub cap at the end of each axle for providing a lubrication compartment for the wheel bearings, said assembly comprising:

• a conduit support carried by an end of an axle and defining a channel extending axially therethrough;
• a tubular conduit having a rigid portion and a flexible portion, said rigid portion extending axially through said conduit support and communicating with the interior of said axle;
• a stationary shaft member having an air passageway extending axially therethrough and communicating with said tubular conduit;
• a housing attachable to the exterior of a hub cap for rotation therewith, said housing defining a centrally disposed channel therein and being rotatably mounted on said stationary shaft member such that said air passageway in said shaft member communicates with said channel in said housing, whereby airflow is directed from said axle through said tubular conduit and said stationary shaft member to said rotatable housing;
• a rotary union comprising a rotary element and a stationary element, said rotary union being disposed in said central channel in said housing;
• and
• an air hose assembly communicating said air passageway in said rotatable housing with at least one of the vehicle tires, said air hose assembly comprising, an air hose, a first fitting carried by said housing and communicating with said air passageway therein, a first pressure actuated check valve disposed within said first fitting, a second fitting carried by a first end portion of said air hose, said second fitting being adapted to be coupled with said first fitting and hold said check valve in an open position such that air can pass therethrough into said air hose, a third fitting carried by a second end of said air hose, said third fitting being adapted to be coupled with the vehicle tire, and a second pressure actuated check valve carried by said third fitting for preventing air loss from the vehicle tire in the event of an air leak in said air hose.