This application relates generally to tire inflation systems and the components thereof.
This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Automatic tire inflation systems (ATIS) may be used to control vehicle tire pressure by adding fluid to one or more vehicle tires as needed during vehicle operation. An automatic tire inflation system may include a rotary union generally configured to convey pressurized fluid from a vehicle-mounted fluid supply to rotating or rotatable tires. The rotary unions may, for example, be threadably mounted within a hubcap of a vehicle or a rotary union may be mounted to a hubcap using another type of connection that does not permit rotational adjustment of the rotary union to align a rotary union hose connection with a tire valve. Likewise, hubcaps may commonly be attached to a wheel hub using a connection that does not permit rotational adjustment. Accordingly, installation and maintenance of ATIS systems may commonly involve over-tightening or under-tightening a rotary union connection to a hubcap increasing risk of damage to the rotary union and associated ATIS components.
There is a need for a rotary union that allows for ready positioning of a hose connection with respect to a tire valve.
A rotary union comprising a rotor body having a first end and a second end, the first end comprising a cylindrical lug having a smooth outer surface configured to freely rotate in a hubcap having a smooth bore configured to receive the cylindrical lug, the rotor body forming a fluid channel extending from the first end to a surface of the body. The rotary union further comprising a tubular member having a first end sealingly disposed in the fluid channel at the first end of the rotor body.
A hubcap comprising a cylindrical body having a first end and a second end, the first end being enclosed by an outer face, the outer face having a cylindrical orifice formed at the center of the face, the orifice comprising a smooth bore; the second end comprising threads configured for threaded engagement with a vehicle hub.
A rotary union comprising a body having a first end and a second end, the first end comprising a smooth lug, the lug having a groove formed circumferentially around the outer diameter of the lug; the body forming a fluid channel extending from the first end to a surface of the body; and a tubular member having a first end sealingly disposed in the fluid channel at the first end of the body.
A hubcap and rotary union comprising a cylindrical hubcap body having a first end and a second end, the first end being enclosed by an outer face, the outer face forming an orifice at the center of the face, the orifice having a smooth bore, the second end comprising threads configured for threaded engagement with a vehicle hub; and a rotary union body having a first end and a second end, the first end comprising a smooth lug, the lug having a groove formed circumferentially around the outer diameter of the lug, the body forming a fluid channel extending from the first end to a surface of the body; a tubular member having a first end sealingly disposed in the fluid channel at the first end of the body; the smooth lug being rotatably disposed in the orifice, and a retaining ring disposed in the groove so as to retain the lug in the orifice.
A method of assembling a rotary union and a hubcap, the method comprising providing a rotary union body having a first end and a second end, the first end comprising a smooth lug, the lug having a groove formed circumferentially around the outer diameter of the lug, the body forming a fluid channel extending from the first end to a surface of the body, the rotary union body having a tubular member having a first end sealingly disposed in the fluid channel at the first end of the body; disposing a retaining ring in the groove; providing a hubcap comprising a cylindrical hubcap body having a first end and a second end, the first end being enclosed by an outer face, the outer face forming an orifice at the center of the face, the orifice having a smooth bore, the second end comprising threads configured for threaded engagement with a vehicle hub; compressing the retaining ring in the groove and inserting the lug and retaining ring into the smooth bore at the outer face; and translating the lug and retaining ring through the smooth bore until the retaining ring emerges from the smooth bore and expands, the lug being thus rotatable disposed in the smooth bore.
A combined hubcap and rotary union comprising a hubcap having an outer face and a smooth-bore orifice formed at the center of the outer face; and a rotary union body having a smooth lug, the lug having a groove formed circumferentially around an outer diameter of the lug, the smooth lug being rotatably disposed in the orifice, and a retaining ring disposed in the groove so as to retain the lug in the orifice.
This disclosure is generally related to rotary unions and automatic tire inflation systems including rotary unions. A rotary union may be disposed so as to help convey pressurized fluid from a vehicle-mounted fluid supply to rotating or rotatable tires. For example, a rotary union may be mounted in a hubcap and include components for communicating fluid from a pressurized vehicles axle to a hose connection providing sealed fluid communication with a tire valve of a rotatable tire. Rotary unions as described herein may include a rotor body including a cylindrical lug having a smooth outer surface configured to rotate in a hubcap bore. The rotor body may be securely retained within the hubcap yet rotatable with respect to the hubcap so that an outlet port of the rotor body may be aligned with the tire valve of a tire. Accordingly, hoses used for routing fluid from the rotary union to the tire valve may be more easily connected without stressing the rotary union or hose tubing. Advantageously, this may simplify installation of rotary unions and prevent inadvertent damage to inflation system components during installation or maintenance.
A rotary union configured for mounting within and freely rotating in a hubcap bore may be included in a commercial truck or other vehicle, such as shown in
The vehicle 2 may be provided with an automatic tire inflation system that may use pressurized air from the vehicle's air brake system or some other source of pressurized air to maintain the tires at a desired air pressure. For example, pressurized air may be directed along or through an axle and routed to a rotary union mounted in the hubcap. A rotary union may communicate fluid to one or more air hoses 14. The hoses 14 may communicate fluid to and from the tires 12. The tire 12 may, for example, be a standard single tire or a wide-base tire, such as a super-single tire, as used in commercial vehicles.
An automatic tire inflation system may further include other components, including, for example, a pressure regulator (not shown). A pressure regulator may, for example, be mounted in a sealed control box including an electronic control board and processor suitable for controlling the pressure regulator. The pressure regulator may receive pressurized fluid from a fluid pressure source, such as a vehicle air brake system air supply or a step-up or booster pump, and control the pressure of fluid from the fluid pressure source so as to provide fluid pressure at a level suitable for inflating the tires, such as, for example, a fluid pressure of 110 psi. Pressurized fluid may flow from the pressure regulator through a conduit to the axles. From there, the fluid may flow through conduit fluid lines in or along the axle, or through the axle (if sealed) to a rotary union disposed within a hubcap.
An embodiment of a rotary union configured for rotatable mounting within a hubcap bore is shown in
With further reference to
As shown in
The rotor body 28 may be rotatably mounted within the central bore 30. For example, lug 32 may include a cylindrical body 41 with a smooth outer surface. The hubcap central boss 34 may have a corresponding smooth inner surface. The interface between the lug 32 and the hubcap central boss 34 may provide suitably low friction to allow for rotation. Accordingly, the rotor body 28 may be rotated with respect to the hubcap when a user applies a manual level of torque. Thus, the position of an outlet port 29 and/or hose connection device 31 may be readily aligned with a tire valve.
In some embodiments, an annular seal 17 may be disposed at the hubcap-rotary union interface. Such a seal 17 may be an O-ring, lip seal or any other suitable seal configuration, and may comprise a variety of materials, such as rubber, silicone, nylon, oilite or graphite. The seal 17 may provide some friction between the lug and the central bore 30 but may still allow the rotor body 28 to rotate in the central bore 30. The seal 17 may further be used to provide contaminant ingress protection and to provide a seal against lubricant leakage from the hubcap interior.
In some embodiments, as seen in
As further shown in
In some embodiments, a pressure relief valve 42 may also be installed in a wall or face of the hubcap 16 so as to vent an excess pressure event from the interior of the hubcap. Such a relief valve could be a one-way valve such as a duckbill valve, non-return valve, ball check valve, or other style of check valve wherein materials are only allowed to pass from the interior of the hubcap to the exterior of the hubcap. Such an excess pressure event may be initiated through a leak of the tire inflation components, overheating, or other events that may increase the pressure of the interior of a hubcap. In such an embodiment, it is not necessary to shield the vent to prevent contaminants from entering through the vent and the fit at the hubcap-rotary union interface may be of a close tolerance to attenuate the possible ingress of contaminants at said interface. However, a vent shield 49 as seen in
In other embodiments, as seen in
In some embodiments, rotor body 28 may include a lug 32 comprising one or more grooves running axially along the lug 32. The grooves may further provide a flow path for venting of excess pressure. In some embodiments, such as for rotary unions used on hubcaps with non-liquid lubricant, the annular seal may be omitted to better allow pressurized gases to escape the hubcap. Addition of such grooves may better permit venting of pressurized gases.
Some embodiments may include a vent shield 49, the shield 49 may then cover hubcap vents so as to prevent contaminants from entering the hubcap 16 through the vents 44. For embodiments where the shield 49 does not protect a vent, the shield may still be included so as to prevent contaminants ingress at the hubcap-rotary union interface.
In some embodiments, rotary union 18 may be shaped so that it may be inserted within the central bore 30 and held within the hubcap central boss 34, including without using a retaining ring 36. For example, as shown in each of
As shown in
Although the disclosed subject matter and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the subject matter as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition, or matter, means, methods and steps described in the specification. As one will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. For example, although the disclosed apparatus, systems and methods may be described with reference to a manual or manually-activated pressure reduction valve, an electric valve or other automatic electronic or mechanical valve may be used to accomplish relatively rapid reduction of fluid pressure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, systems or steps.
This application claims priority to U.S. Provisional Patent Application 62/885,654 titled “Smooth Bore Hubcap and Rotary Union” filed Aug. 12, 2019, which is hereby entirely incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/046014 | 8/12/2020 | WO |
Number | Date | Country | |
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62885654 | Aug 2019 | US |