HK1186440B - Valve stem with auxiliary port - Google Patents

Description

Valve stem with auxiliary port

Cross Reference to Related Applications

This application claims priority to U.S. provisional patent application 61/376144 entitled "valve stem with auxiliary port," filed on 23/8/2010, the entire contents of which are incorporated herein by reference.

Technical Field

The methods and apparatus disclosed herein relate generally to tire pressure maintenance.

Background

Automatic tire inflation systems may rely on standard vehicle tire valve stems. Standard vehicle tire valve stems do not provide auxiliary ports that allow alternative paths for air flow or for installation of auxiliary devices. There is a need for a valve stem with an auxiliary port suitable for use in an automatic tire inflation system.

Disclosure of Invention

A wheel end assembly comprising a hubcap mounted to a wheel rotatable on an axle, said wheel end assembly comprising: a rotary union in or mounted to the hubcap, the rotary union being in sealed fluid communication with an air pressure supply; an air hose having a first end and a second end, the first end being connected to the swivel joint to allow air to flow through the air hose from the air pressure supply; and a valve stem mounted to the wheel so as to allow inflation of the pneumatic tire, the valve stem including a first one-way valve and an auxiliary port, wherein the second end of the air hose is connected with the valve stem so as to allow fluid communication of pressurized air with the valve stem. The wheel end assembly further includes one of an air pressure gauge, a tire pressure monitoring system sensor, a temperature sensor, and a second one-way valve mounted to the auxiliary port. The second one-way valve includes a pressure relief valve oriented to release air from the pneumatic tire or the second one-way valve is oriented to allow air to be inflated into the pneumatic tire.

An automatic tire inflation system for a pneumatic tire mounted to a wheel, the wheel having a hubcap mounted thereon, the automatic tire inflation system comprising: an air pressure supply source; a rotary union within or mounted to the hubcap, the rotary union being in sealed fluid communication with the air pressure supply source; an air hose having a first end and a second end, the first end being connected to the swivel joint to allow air to flow through the air hose from the air pressure supply; and a valve stem mounted to the wheel so as to allow inflation of the pneumatic tire, the valve stem including a one-way valve and an auxiliary port, wherein the second end of the air hose is connected to the valve stem so as to allow fluid communication of pressurized air with the valve stem.

An improved valve stem having a fluid passageway disposed therein along a long axis of the valve stem, said improved valve stem comprising: a base end configured for mounting to a wheel; a column end having a schrader valve mounted within the fluid passage; one or more auxiliary ports disposed between the base end and the post end, the one or more auxiliary ports in fluid communication with the fluid channel; a sleeve translatably disposed about the valve stem to allow the one or more auxiliary ports to be closed and opened; and a first seal disposed adjacent the one or more auxiliary ports for sealing engagement between the valve stem and the sleeve.

Drawings

FIG. 1 illustrates one embodiment of a valve stem with an auxiliary port.

FIG. 2 illustrates one embodiment of a vehicle with an automatic tire inflation system.

Fig. 3 illustrates the automatic tire inflation system of fig. 1 in greater detail.

Fig. 4A and 4B illustrate another embodiment of a valve stem with an auxiliary port and a sleeve in a closed position covering the auxiliary port.

Fig. 5A and 5B illustrate the embodiment of fig. 4A and 4B with the sleeve in an open position not covering the auxiliary port.

Detailed Description

As can be seen in the embodiment of fig. 1, the improved tire valve stem 2 may include a post 4 and a base 6. The base 6 may be fitted within a seal 8 configured to allow the base 6 to be snap-in mounted in a bore of a wheel rim (not shown) in much the same way as a standard tyre valve stem. The nut 10 and washer 12 may be removably mounted to the base 6, such as by a threaded connection, to retain the base 6 within the seal 8. The seal may be rubber, polyurethane, nylon or any suitable sealing material. In some embodiments, the base 6 may be retained within the seal by any suitable means, such as by a friction fit, a flange, a locking tab, an adhesive, or the like. Alternatively, the base 6 may be welded or screwed directly into a hole in the rim (not shown). The base 6 may include an air channel 14 positioned generally along the long axis of the base 6 that allows air to flow through the base 6. An air filter 16 may be mounted to a first end 18 of the base 6 to prevent contaminants from the pneumatic tire from entering the valve stem 2.

The post 4 may be removably mounted to the second end 20 of the base 6, for example by way of a threaded attachment. Of course, the post 4 may be removably mounted to the base 6 by any suitable means, such as by friction fit, adhesive, retaining pins, etc., or the post may be permanently mounted to the base. In other embodiments, the post 4 and base 6 may be a one-piece article of manufacture. In such embodiments, the words "post" and "base" may simply represent portions of the product. A seal 22 may be provided to seal the connection between the post 4 and the base 6. The seal may be, for example, an O-ring, a compression gasket, or an adhesive, and may be of any suitable material, such as rubber, polyurethane, nylon, or any suitable sealing material. The post 4 may include an air channel 24 positioned generally along the long axis of the post 4 to allow air to flow through the post 4. The first end 26 of the post 4 is mounted to the base 6, which may allow air to flow between the air passage 24 of the post 4 and the air passage 14 of the base 6. A valve spool 28, such as a schrader valve, may be removably mounted (e.g., by threaded connection) within the second end 30 of the column 4. The valve spool 28 may include a one-way valve that allows air to flow into the air passage 24 in one direction but not the other. In the disclosed embodiment, the spool may allow air to flow into the air passage 24 through the second end 30 of the stem 4 but not in the other direction.

The post 4 may be provided with one or more auxiliary ports 32 extending in a generally radial direction from the air passage 24 to the outer surface of the stepped portion 4. The auxiliary port 32 may allow various component members to be mounted to the valve stem 2. The auxiliary port 32 may be threaded, such as 1/8NPT (american standard taper pipe threading), to allow for removable installation of these components. In one embodiment, a one-way pressure relief valve may be removably mounted to the auxiliary port to allow for relief of tire pressure to atmosphere in excess of the desired pressure. For example, air may be inflated into the cold tire to achieve the manufacturer's recommended tire pressure. As the tire heats up in use, the tire pressure may increase beyond the manufacturer's recommended tire pressure. Similarly, as a tire is driven from a lower elevation to a higher elevation, tire pressure may increase, and therefore, excess tire pressure may need to be relieved.

For example, an automatic pressure relief valve (not shown) may be mounted to the auxiliary port and configured to remain closed until the tire pressure approximately exceeds the manufacturer's recommended tire pressure or other desired pressure. When the tire pressure exceeds the recommended tire pressure, the pressure relief valve may open to allow air to escape, thereby reducing the tire pressure. When the tire pressure reaches approximately the recommended pressure, the pressure relief valve may close to prevent further air loss. Thus, the pressure relief valve may be configured to automatically open when the tire pressure increases above a pressure threshold and to automatically close when the tire pressure drops below the pressure threshold.

In other embodiments, the tire pressure monitoring sensor and/or the tire temperature monitoring sensor may be removably mounted to the auxiliary port. For example, tire pressure and/or temperature monitoring sensors may include those manufactured by BendixCommercialVehiclesystemsTire Pressure Monitoring System (TPMS) wireless tire sensors. The auxiliary port may provide ease of mounting such a sensor to a vehicle without changing the rim.

In yet another embodiment, a tire valve stem with an auxiliary port may be used with a tire inflation system, such as disclosed in U.S. patent nos. 6698482, 6105645 or U.S. published application No. 2009/0283190. As shown in fig. 2, the vehicle 100 may include a truck 102 and a trailer 104. Truck 102 may include one or more drive axles 106 as part of the vehicle powertrain. Truck 102 may further include a steer axle (not shown in detail) having a pivotable main axle capable of providing steering capability to vehicle 100. The trailer 104 may include one or more fixed axles (not shown). Each axle may have one or more wheels 108 mounted thereto. A pneumatic tire 110 may be mounted to each wheel 108.

The vehicle 100 may be provided with an automatic tire inflation system (such as that shown in fig. 2) that maintains the tires at a desired air pressure using pressurized air from the vehicle's air brake system or some other source. An automatic tire inflation system may be used to control the gas pressure of one or more tires 110 mounted to a steer axle (not shown), drive axle 106, or trailer axle (not shown). An automatic tire inflation system may include one or more air hoses 112 in fluid communication with each tire 110 for passing air from an air pressure source to one or more tires 110, and vice versa.

Figure 2 illustrates in more detail various embodiments of an automatic tire inflation system for trailer tires. Trailer 200 may include two axles 202 and 204. Some trailers may have dual tires 206 and 208 mounted at each end of these axles, as may be seen with respect to axle 202. Other trailers may have one wide base tire 210 mounted at each end of the axle, as may be seen with respect to axle 204. In general, an automatic tire inflation system may include a pressure regulator 214, and one or more rotary air connections or rotary unions 216 and 218 mounted in or near the axle ends as described in more detail below. The pressure regulator 214 may receive pressurized air from an air pressure source 220 via a conduit 212. The air pressure source 220 may comprise, for example, a vehicle air brake system air supply, or a boost or booster pump. The pressure regulator 214 may control or reduce the air pressure from the air pressure source 220 to an air pressure level suitable for inflating the tires 206, 208, 210, such as 110 psi. Pressurized air may flow from pressure regulator 214 through conduit 222 to axles 202 and 204.

Axles 202 and 204 may be entirely solid or hollow, or partially solid or hollow, and may be configured in a variety of ways. For illustrative purposes only, axles 202 and 204 are hollow. For example, in some embodiments, the axle may include a solid beam having an axle (not shown) attached to each end. The axle spindle may be configured to allow mounting of a wheel bearing on which a wheel hub (not shown) may be rotatably mounted. In other embodiments, the axle may comprise a hollow tube with a spindle attached to each end. The spindle may be hollow, resulting in a hollow axle that is open at each end. Alternatively, the spindle may be solid in whole or in part, resulting in a hollow axle that is closed at each end.

If the axle is open at the ends, the axle may be sealed by a plug or cap, such as disclosed in one of U.S. patent nos. 5584949, 5769979, 6131631, 6394556, 6892778, and 6938658, allowing the hollow axle to retain pressurized air and support an air conduit or rotating air connection (or components thereof). The open end may also be provided with a plug or cap that not only serves to support an air conduit or a rotary air connection (or a component thereof), but also serves to seal the hollow axle to retain pressurized air, such as the plug or cap disclosed in one of U.S. patent nos. 6325124 and 7273082.

In the embodiment of fig. 2, axles 202 and 204 may be hollow sealed axles. In one embodiment, the axle 204 may be hollow and may be sealed to serve as a pressurized air conduit. The air conduit 222 may be sealingly connected to the axle 204, allowing pressurized air to flow from the pressure regulator 214 to the axle 204. Pressurized air may flow through the axle 204 to a rotary air connection 216 mounted in or near the end of the spindle, as described in more detail below. The air hose 224 may be connected to a valve stem (not shown) that turns the air connection 216 to the wheel 209 on which the tire 210 is mounted, thus allowing pressurized air to flow to the tire 210, or out of the tire 210.

In some embodiments, air conduit 222 may be sealingly connected to a tee 226 to allow pressurized air to flow to both axle 204 and axle 202. Air conduit 228 may allow pressurized air to flow from tee 226 to conduit 230 disposed within axle 202. Axle 202 may carry an air conduit 230 to communicate pressurized air to rotary air connection 218, such as disclosed in U.S. patent nos. 6325124 and 7273082. Air hose 232 may connect rotary air connection 218 to valve stems 219 and 221 of wheel 211 on which tires 206 and 208 are mounted, allowing pressurized air to flow to tires 206 and 208, or from tires 206 and 208. In other embodiments, if axle 202 is solid, a channel may be drilled into axle 202, allowing all or a portion of conduit 230 to be positioned within axle 202.

Referring to fig. 1 and 3, the base 6 of the modified valve stem 2 with auxiliary ports may be mounted to each rim of tires 206, 208, and 210 in place of the standard tire valve stems 219 and 221. The air hoses 232 and 224 may be connected to the second end 30 of the modified valve stem 2 by threaded attachment. In operation, pressurized air from the air supply may pass through the air lines 222, 228, and 230 of the automatic tire inflation system to the rotary joints 216 and 218, and from the rotary joints 216 and 218 to the valve stem 2. In each valve stem 2, pressurized air may open the valve cartridge 28, thus allowing air to pass through the valve cartridge 28 via the air passages 24 and 14 and into the tire via the filter 16. If excessive pressure develops within the tire, air may flow back through filter 16, back through air passage 14 into air passage 24, and escape via an automatic pressure relief valve (not shown) mounted in auxiliary port 32. The valve core 28 may remain closed to prevent air from flowing back from the tire into the automatic tire inflation system. In applications where an automatic pressure relief valve is not required, a manual pressure relief valve may be mounted to the auxiliary port 32 for use with an automatic tire inflation system. In such systems, if the tires are deemed to be over pressurized, the driver or service personnel may manually deflate the tires to a level below the desired tire pressure, for example, prior to starting the vehicle. When the automatic tire inflation system is activated, the pressurized air will automatically bring the tire back to the desired tire pressure.

If other types of devices, such as air pressure gauges (not shown), are installed within the auxiliary port 32, air may be communicated between the tire and the device through the air passages 14 and 24, thus allowing the device to obtain tire pressure or other air properties (e.g., temperature). In a further embodiment, a one-way valve, such as a schrader valve, may be mounted to the auxiliary port to allow another entry point for pressurized air. This embodiment may allow air to be inflated into the tire without removing the automatic tire inflation system air hose from the second end 30 of the post 4.

Fig. 4A and 4B, and fig. 5A and 5B are views showing another embodiment of the modified valve stem 2. The post 4 may include a sleeve 40 that may translate along the post 4 to cover and uncover one or more auxiliary ports 32. The sleeve may be of any suitably rigid or semi-rigid material, such as metal, plastic, rubber or ceramic. One or more seals 42 may be disposed on the stem to allow sealing engagement of the post 4 with the sleeve 40. For example, the seal 42 may be mounted circumferentially around the interior of the sleeve 40 in a groove 44 of suitable size. Alternatively, more seals may be mounted circumferentially around the post 4 in suitably sized grooves (not shown). The seal 42 may be positioned adjacent the auxiliary port 32 and may provide a sealing interface with the sleeve 40. The seal 42 may be an O-ring, lip seal, or any suitable seal, and may be of any suitable material, such as nitrile or rubber. In the first position, as shown in fig. 4, the sleeve 40 may cover the auxiliary port 32, and the seal 42 may provide a sealing interface with the sleeve 40 above and below the auxiliary port 32, thereby preventing fluid flow through the auxiliary port 32. In a second position, as shown in fig. 5, the sleeve 40 may be disengaged from at least one of the seals 42 above or below the auxiliary port 32, thereby allowing fluid to flow through the auxiliary port 32.

The sleeve 40 may be slidably translated from a first position to a second position, and from the second position to the first position. In one embodiment, the first position may be a default position or "closed" position, and the sleeve may be biased toward the first position by a spring 46. The first end 48 of the spring 46 may sit on a shoulder 50 of the post. The second end 52 of the spring 46 may sit on a shoulder 54 provided on the inner surface of the sleeve 40. In the default or "closed" position of the sleeve 40, the spring 46 may be slightly compressed to urge the sleeve 40 into that position along the post 4. A locking ring 56 or nut may be provided around the post 4 to prevent the sleeve 40 from translating along the post 4 away from the spring 46. Thus, in the default or "closed" position of the sleeve 40, the spring 46 may urge the sleeve 40 against the locking ring 56.

The sleeve 40 may be manually translated along the post 4 from the "closed" position shown in fig. 4 to a second or "open" position shown in fig. 5 to allow fluid communication through the auxiliary port 32, e.g., air may be vented from the air passage 24 to atmosphere, or vice versa. Translation of the sleeve 40 from the "closed" position to the "open" position may cause the spring 46 to compress such that the sleeve 40 will return to the "closed" position along the post 4 when the manual force applied to the sleeve 40 is released.

In some embodiments, a protective skirt or bellows 58 may extend from the sleeve 40 to the first end 26 of the post 4. The bellows 58, shown in outline in fig. 4 and 5, may be of a flexible material such as rubber, fabric or silicone. Bellows 58 may be sealed to sleeve 40 and to first end 26 of column 4, thereby preventing contaminants from collecting within sleeve 40 and around spring 46.

In other embodiments, the sleeve 40 may be threadably mounted to the post 4 and may be rotationally translatable along the post 4 along these threads (not shown). For example, instead of using a spring 46, the post 4 may be threaded, and the interior of the sleeve 40 may also be threaded to allow the sleeve 40 to be threadably mounted to the post 4. In some embodiments, threads may be used for sealing. If the sleeve 40 is threaded to the post 4, the sleeve 40 may be rotated about the post 4 such that the sleeve 40 can translate along the post 4 from a "closed" position to an "open" position, and vice versa.

In yet another embodiment, the sleeve 40 may be retained in the "closed" position or the "open" position by detents or ridges provided on the post or any suitable mechanism for preventing the sleeve 40 from translating along the post 40 without the application of force (e.g., a groove in the sleeve 40 for engaging one or more seals 42).

As described above, when modified valve stem 2 of fig. 4 and 5 is installed on a wheel in place of standard tire valve stems 219 and 221, the modified valve stem may allow a user to manually deflate the tire to, for example, relieve an overpressure without disconnecting air hoses 232 and 224 of the automatic tire inflation system. Likewise, the modified valve stem 2 may be used in addition to a standard tire valve stem, for example, as a separate valve stem mounted to a wheel and similarly used to allow manual deflation of a tire.

One or more auxiliary ports 32 may be used in the embodiments of fig. 4 and 5. The auxiliary port 32 may be threaded or unthreaded and may be large enough to allow the tire to deflate relatively quickly compared to deflation using a standard valve stem. For example, the number and size of the auxiliary ports 32 may be set sufficient to allow the tire to deflate by about 10psi in about 10 seconds. In other embodiments, the number and size of auxiliary ports may be sufficient to be used with the system of U.S. provisional patent application serial No. 61/494327, entitled "automatic tire inflation system using manual pressure release," the entire disclosure of which is incorporated herein by reference.

In yet another embodiment, one or more modified valve stems having auxiliary ports may be provided in addition to standard valve stems. Other apertures may be provided in the wheel to accommodate modified valve stems on the wheel in addition to standard valve stems.

Although the present invention 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 invention 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 of 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. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims (3)

1. An improved valve stem (2) having a fluid passage (24) disposed therein along a long axis of the valve stem, said improved valve stem (2) comprising:

a base end (6) configured for mounting to a wheel;

a column end (4) having a one-way valve (28) mounted within the fluid passage (24);

one or more auxiliary ports (32) disposed between the base end (6) and the column end (4), the one or more auxiliary ports (32) being in fluid communication with the fluid channel (24);

a sleeve (40) translatably arranged around the valve stem (2) so as to allow closing and opening of the one or more auxiliary ports (32);

a first seal (42) disposed adjacent the one or more auxiliary ports (32) for sealing engagement between the valve stem (2) and the sleeve (40), the first seal (42) disposed between the one or more auxiliary ports (32) and the column end (4);

a locking ring (56) disposed between the first seal (42) and the column end (4);

a second seal (42) arranged for sealing engagement between the valve stem (2) and the sleeve (40), the second seal (42) being arranged around the valve stem (2) adjacent the one or more auxiliary ports (32) and between the one or more auxiliary ports (32) and the base end (6); and

a spring (46) slidably disposed about the valve stem (2), a first end of the spring (46) being between the second seal (42) and the base end (6), and a second end of the spring (46) abutting the sleeve (40) to urge the sleeve (40) against the locking ring (56);

wherein, when the sleeve (40) is urged against the locking ring (56), the one or more auxiliary ports (32) are closed and the first and second seals (42) sealingly engage the valve stem (2) and the sleeve (40); and is

Wherein the sleeve (40) is translatable under force along the valve stem (2) away from the first seal (42) against spring pressure to open the one or more auxiliary ports (32) and allow fluid flow therethrough.

2. The improved valve stem (2) of claim 1 further comprising: a bellows (58) sealed at a first end to the sleeve (40) and at a second end to the valve stem (2) between the first end of the spring (46) and the base end (6).

3. The improved valve stem according to claim 1, wherein the stem end (4) and the base end (6) are threadably engageable.