Tire Inflation System Having a Pressure Equalization Valve Assembly

A tire inflation system for a vehicle. The tire inflation system may include a pressure equalization valve assembly that may receive the pressurized gas from a pressurized gas source and may control the flow of pressurized gas with respect to a first tire and a second tire.

TECHNICAL FIELD

This patent application relates to a tire inflation system having a pressure equalization valve assembly.

BACKGROUND

A dual tire pressure balance system is disclosed in U.S. Pat. No. 6,457,502.

SUMMARY

In at least one embodiment a tire inflation system for a vehicle is provided. The tire inflation system may include a pressurized gas source that supplies a pressurized gas and a pressure equalization valve assembly. The pressure equalization valve assembly may receive the pressurized gas from the pressurized gas source and may be fluidly connected to a first tire and a second tire. The pressure equalization valve assembly may permit the pressurized gas to flow between the first tire and the second tire to substantially equalize an inflation pressure of the first tire with an inflation pressure of the second tire.

In at least one embodiment a tire inflation system for a vehicle is provided. The tire inflation system may include a pressurized gas source that supplies a pressurized gas and a pressure equalization valve assembly. The pressure equalization valve assembly may receive the pressurized gas from the pressurized gas source via a delivery conduit and may be fluidly connected to a first tire and a second tire with first and second connection conduits, respectively. The pressure equalization valve assembly may inhibit pressurized gas from flowing between the first tire and the second tire when an inflation pressure of either the first tire or an inflation pressure of the second tire decreases by a threshold pressure drop amount.

In at least one embodiment a tire inflation system for a vehicle is provided. The tire inflation system may include a pressurized gas source, a pressure equalization valve assembly, an outlet valve, and an inlet valve. The pressurized gas source may be disposed on the vehicle and may be configured to provide a pressurized gas. The pressure equalization valve assembly may be fluidly connected to a first tire and a second tire and may control the flow of the pressurized gas to a first tire and a second tire. The outlet valve may be fluidly connected to the pressure equalization valve assembly and may control flow of the pressurized gas to the pressure equalization valve assembly. The inlet valve may be fluidly connected to the outlet valve. The inlet valve may control the flow of the pressurized gas from the pressurized gas source to the outlet valve. The pressure equalization valve assembly may open to permit the pressurized gas to flow to the first tire and the second tire when either an inflation pressure of the first tire or an inflation pressure of the second tire is less than a target tire pressure and the inlet valve and the outlet valve are open.

DETAILED DESCRIPTION

Referring toFIG. 1, an exemplary vehicle10is shown. The vehicle10may be of any suitable type, such as a motor vehicle like a truck, bus, farm equipment, military transport or weaponry vehicle, or cargo loading equipment for land, air, or marine vessels and may include a trailer in one or more embodiments.

The vehicle10may include a plurality of axles or axle assemblies12that may support and facilitate rotation of at least one wheel assembly20. For clarity, a fragmentary portion of each axle assembly12is shown inFIG. 1. An axle assembly12may or may not be configured as a drive axle that may provide torque to at least one associated wheel assembly20. In addition, an axle assembly12may or may not be configured to steer the vehicle10. An axle assembly12may be configured as or may include a steering knuckle assembly.

Each wheel assembly20may include at least one inflatable tire22that may be mounted on an associated wheel24. Each tire22may have a tire valve26that may facilitate inflation of the tire22. The tire valve26may have any suitable configuration. For example, the tire valve26may be configured as a Schrader valve in one or more embodiments. The tire valve26may extend through a hole in an associated wheel24and may be configured to provide pressurized gas to a tire chamber that may be at least partially defined by the tire22and the wheel24. Each tire valve26may be normally closed to inhibit pressurized gas from exiting the tire22through the tire valve26; however, the tire valve26may be held in an open position when coupled to a tire inflation system30as will be discussed in more detail below. As such, the tire valve26may be open when properly coupled to the tire inflation system30and may close when the tire valve26is disconnected from the tire inflation system30. InFIG. 1, the tire valve locations are generalized for illustration purposes and are not intended to be limiting.

The tire inflation system30may be mounted on the vehicle10. The tire inflation system30may monitor or determine tire pressure and may inflate one or more tires22. More specifically, the tire inflation system30may be configured to provide a pressurized gas or pressurized gas mixture to one or more tires22. For clarity, the term “pressurized gas” may refer to a pressurized gas or a pressurized gas mixture in this application. The tire inflation system30may include a pressurized gas source32, a gas supply subsystem34, and a control system36.

The pressurized gas source32may be configured to supply and/or store a volume of a pressurized gas or pressurized gas mixture, such as air and/or nitrogen. For example, the pressurized gas source32may include a tank and/or a pump like a compressor that may be driven by a vehicle engine or vehicle power source. The pressurized gas source32may be disposed on the vehicle10and may be configured to provide a pressurized gas or pressurized gas mixture at a pressure that is greater than or equal to a target tire pressure or a target inflation pressure of a tire22.

The gas supply subsystem34may fluidly connect the pressurized gas source32to one or more tires22. The gas supply subsystem34may include one or more conduits40, such as a hose, tubing, pipe, or combinations thereof, which may provide pressurized gas to at least one tire22via a corresponding tire valve26. In at least one embodiment, the gas supply subsystem34may include an inlet valve42, at least one outlet valve44, a first pressure sensor46, a second pressure sensor48, and at least one pressure equalization valve assembly50.

The inlet valve42may control the flow of pressurized gas from the pressurized gas source32. More specifically, the inlet valve42may enable or disable the flow of pressurized gas from an outlet of the pressurized gas source32to at least one outlet valve44. Operation of the inlet valve42may be controlled by the control system36. For instance, the inlet valve42may include or may be controlled by an actuator, such as solenoid, that may actuate the inlet valve42between an open position and a closed position. In the open position, pressurized gas may flow from the pressurized gas source32to a manifold52. The manifold52may be disposed between the inlet valve42and one or more outlet valves44and may distribute pressurized gas to at least one delivery conduit60. In the closed position, pressurized gas may be inhibited from flowing from the pressurized gas source32to the manifold52. In at least one embodiment, the inlet valve42may be normally closed under predetermined operating conditions, such as when the vehicle10is not operational or turned off or when the vehicle engine is not running. As such, the inlet valve42may inhibit depressurization of the pressurized gas source32in the event of a downstream leak.

The outlet valve44may control the flow of pressurized gas to a pair of tires22. More specifically, the outlet valve44may enable or disable the flow of pressurized gas from the manifold52to a delivery conduit60and to the pressure equalization valve assembly50and an associated tire22. InFIG. 1, five outlet valves44are shown, although it is contemplated that a greater or lesser number of outlet valves44may be provided. The outlet valves44may be associated with different tires22and different delivery conduits60. Moreover, each outlet valve44may be actuated independently of the inlet valve42and independently of each other. As such, the inflation and pressure assessment of different tires22or sets of tires22may be independently controlled. Operation of the outlet valve44may be controlled by the control system36. For instance, the outlet valve44may include or may be controlled by an actuator, such as solenoid, that may actuate the outlet valve44between an open position and a closed position. In the open position, pressurized gas may flow from the manifold52through the delivery conduit60and to a corresponding pressure equalization valve assembly50. In the closed position, pressurized gas may be inhibited from flowing from the manifold52to a corresponding pressure equalization valve assembly50. As such, pressurized gas may not be constantly provided to one or more tires22, which may facilitate the use of pressure pulses to determine tire pressure. In addition, the outlet valve44may allow a delivery conduit60to be vented to the surrounding environment between the outlet valve44and a corresponding pressure equalization valve assembly50. In at least one embodiment, the outlet valve44may be normally closed under predetermined operating conditions, such as when the vehicle10is not operational or turned off or when the vehicle engine is not running.

The first pressure sensor46may be configured to detect the pressure of the pressurized gas provided by the pressurized gas source32. The first pressure sensor46may be of any suitable type and may be fluidly connected to the pressurized gas source32. For example, the first pressure sensor46may be fluidly connected to the pressurized gas source32between the pressurized gas source32and the inlet valve42.

The second pressure sensor48may be configured to detect the pressure of the pressurized gas provided to a tire22and/or the pressure equalization valve assembly50. The second pressure sensor48may be of any suitable type. The second pressure sensor48may be disposed between the inlet valve42and the tire valve26and may be fluidly connected to the manifold52. As such, the second pressure sensor48may be isolated from the pressurized gas source32by closing the inlet valve42. In at least one embodiment, the second pressure sensor48may be disposed between the inlet valve42and one or more outlet valves44so that the second pressure sensor48may be used to detect the pressure of pressurized gas supplied to different tires. Alternatively, multiple second pressure sensors48may be provided that may detect the pressure supplied to a particular conduit40or particular tire22.

A pressure equalization valve assembly50may be configured to receive pressurized gas from the pressurized gas source32via a delivery conduit60and control the flow of pressurized gas. The pressure equalization valve assembly50may be fluidly connected to a pair of tires22. These tires22may be referred to as a first tire and a second tire for convenience in reference. In the text below, the positions of the first tire and the second tire are exemplary and may be interchanged in a given pair of tires22.

The first tire and the second tire may be disposed on different wheels24as is shown with the wheel assemblies20located near the top ofFIG. 1. As such, the pressure equalization valve assembly50may be fluidly connected to different wheel assemblies20that may be disposed on different axles of a common axle assembly12. In addition, the first tire and second tire may be disposed on a common wheel24, as is shown with the four dual tire wheel assemblies20shown near the bottom ofFIG. 1. The first and second tires or each tire in a pair of tires22may have the same target tire pressure in one or more embodiments.

The pressure equalization valve assembly50may be fluidly connected to the first tire via a first connection conduit62. The pressure equalization valve assembly50may be fluidly connected to the second tire via a second connection conduit64. The first connection conduit62and the second connection conduit64may be configured to depress or open an associated tire valve26when installed on the tire valve26in one or more embodiments.

The pressure equalization valve assembly50may provide one or more of the following functions. First, the pressure equalization valve assembly50may facilitate the flow of pressurized gas between the first and second tires to help balance the pressure between the tires. Second, the pressure equalization valve assembly50may terminate the flow of pressurized gas between the first and second tires when the pressure of a tire decreases by more than a threshold pressure drop amount. Third, the pressure equalization valve assembly50may permit pressurized gas to flow to at least one tire when a tire is underinflated. Fourth, the pressure equalization valve assembly50may provide check valve functionality to inhibit backflow of pressurized gas toward the pressurized gas source32. These functions are discussed in more detail below.

The pressure equalization valve assembly50may permit pressurized gas to flow between a first tire and a second tire. More specifically, the pressure equalization valve assembly50may open in response to force exerted by the pressurized gas when a pressure differential exists between the first tire and the second tire to permit pressurized gas to flow from the tire having higher pressure to the tire having lower pressure. As such, the pressure equalization valve assembly50may permit the inflation pressure of the first tire to substantially equalize with the inflation pressure of the second tire, notwithstanding design tolerances of the pressure equalization valve assembly50that may affect when the pressure equalization valve assembly50may open. In addition, the first connection conduit62and the second connection conduit64may be in fluid communication with each other via the pressure equalization valve assembly50when pressurized gas does not enter the pressure equalization valve assembly50via the delivery conduit60.

The pressure equalization valve assembly50may inhibit pressurized gas from flowing between the first tire and the second tire when the inflation pressure of either the first tire or the inflation pressure of the second tire decreases by a threshold pressure drop amount. As such, the pressure equalization valve assembly50may help maintain the pressure of at least one tire22in a pair when the other tire22experiences a major pressure drop, such as a tire blowout that may not permit tire inflation pressure to be maintained. For example, if the first tire experiences a major leak or a blowout, then the pressure equalization valve assembly50may initially permit pressurized gas to flow from the second tire to the first tire. The pressure equalization valve assembly50may terminate the flow of pressurized gas from the second tire to the first tire when the inflation pressure of the first tire and/or the inflation pressure of the second tire decreases by a threshold pressure drop amount. The threshold pressure drop amount may be a predetermined value that may be based on tire attributes or vehicle development testing. In at least one embodiment, the threshold pressure drop amount may be a constant value, such as approximately 20 psi (137.9 kPa). In addition, the threshold pressure drop amount may be measured with respect to a target tire inflation pressure that may be indicative of a desired inflation pressure of the tire22. As such, the pressure equalization valve assembly50may inhibit the flow of pressurized gas between the tires22when the inflation pressure of a tire is less than the threshold pressure drop amount. The inflation pressure of a tire22may be detected in various ways, such as with the second pressure sensor48or a tire pressure sensor70that may be disposed inside the tire22or inside a tire chamber that receives the pressurized gas. Such a tire pressure sensor70may wirelessly communicate with the control system36and may provide a signal or data that is indicative of the inflation pressure of the tire22to the control system36. Tire pressure may also be indirectly detected with a pressure sensor that is disposed outside the tire as is described in U.S. patent application Ser. No. 14/029,884, the disclosure of which is hereby incorporated by reference in its entirety.

The pressure equalization valve assembly50may be configured to permit pressurized gas to flow from the pressurized gas source32to a tire22. The flow of pressurized gas may be enabled by opening the inlet valve42and an outlet valve44associated with the pressure equalization valve assembly50to provide pressurized gas to a corresponding delivery conduit60as previously discussed. For example, the pressure equalization valve assembly50may open in response to force exerted by the pressurized gas when the pressure in the delivery conduit is greater than a downstream pressure in a tire22, the first connection conduit62, and/or the second connection conduit64. As such, pressurized gas may flow to the first tire and/or the second tire when the inflation pressure of the first tire and/or the inflation pressure of the second tire are less than the target tire pressure. The target tire pressure may be a predetermined value that may be based on the make and model of the tire and/or vehicle development testing. In addition, the target tire pressure may account for design tolerances of the pressure equalization valve assembly50such as the tolerance range associated with opening the pressure equalization valve assembly50.

The pressure equalization valve assembly50may act as a check valve to inhibit pressurized gas from flowing from the first tire and/or from the second tire to the pressurized gas source32. Check valve functionality may be integrated with the portion of the pressure equalization valve assembly50that permits or inhibits the flow of pressurized gas between the first and second tires or may be separate from the portion of the pressure equalization valve assembly50that permits or inhibits the flow of pressurized gas between the first and second tires. The pressure equalization valve assembly50may inhibit pressurized gas from flowing from the first tire and/or the second tire into the delivery conduit60or toward the pressurized gas source32when the pressure equalization valve assembly50permits pressurized gas to flow between the first tire and the second tire. As such, the pressure equalization valve assembly50may inhibit backflow and potential tire pressure loss due to a leak or reduced pressure upstream from the pressure equalization valve assembly50.

The control system36may monitor and control operation of the tire inflation system30. The control system36may include one or more electronic controllers or control modules that may monitor and/or control various components of the tire inflation system30. For example, the control system36may be configured to control actuation of the inlet valve42and the outlet valve44to control the flow of pressurized gas. In addition, the control system36may be configured to receive data from the first pressure sensor46, the second pressure sensor48, and/or the tire pressure sensor70, if provided, that may be indicative of pressure. InFIG. 1, communication between the control system36and the first and second pressure sensors46,48is represented by the double arrowed line that is located adjacent to the control system36.

The tire inflation system30in conjunction with the pressure equalization valve assembly50may allow the control system36to more accurately measure and maintain the inflation pressure of fluidly connected tires22. More specifically, tire pressures measurements may be inaccurate when tire pressures are substantially different and a single pressure sensor is used to detect pressure in a configuration in which two tires are connected to a common pressurized gas delivery conduit without a pressure equalization valve assembly50. For example, tire pressure measurements may be inaccurate when a first tire is overinflated and a second tire is underinflated and the first and second tires are fluidly connected to a common delivery conduit without a pressure equalization valve. Providing pressurized gas based on such an inaccurate pressure measurement may further increase the pressure in the overinflated tire and not provide sufficient pressurized gas to the underinflated tire to achieve the target tire pressure. As such, tire pressure equalization and independent flow rate control may not be attained without a pressure equalization valve assembly50even when two tires receive pressurized gas from a common supply conduit.