This invention pertains generally to Central Tire Inflation (CTI) systems. CTI systems are installed in many military vehicles as they enable tire pressure to be lowered as needed to enable the user to benefit from the increased traction available while operating at low tire pressure. CTI systems can be integrated or non-integrated and are typically used with multi-piece wheels in conjunction with beadlock or runflat devices. Prior art multi-piece wheel designs for use with non-integrated and integrated CTI systems fall into three major categories.
A first major category of multi-piece wheel designs includes wheels with features adapted for use with a non-integrated CTI having only external air passages. This type of wheel accepts a non-integrated CTI valve (or valves), and all air passages are external to the wheel (i.e. hoses and/or tubing). The CTI valve is typically fastened to brackets that are attached to the wheel. The wheel is usually a multi-piece wheel (two-piece bolt-together, or two or more piece wheel comprising a useful base, side rim, and lock-ring).
A second category would include wheels with features adapted for use with a non-integrated CTI with both internal and external air passages. This type of wheel accepts a non-integrated CTI valve (or valves), and some of the air passages are internal to the wheel, with the balance requiring external hoses and/or tubing. The CTI valve is fastened directly to the wheel, or fastened to brackets that attach to the wheel. The wheel is, once again, usually a multi-piece wheel (two-piece bolt-together, or two or more piece wheel comprising a useful base, side rim, and lock-ring).
A third category includes wheels including features adapted for use with an integrated CTI having only internal air passages. This type of wheel accepts an integrated CTI valve (or valves), and all air passages are internal to the wheel. The CTI valve is fastened directly to the wheel. The wheel is typically, but not necessarily, a two-piece wheel. (See, e.g., U.S. Pat. No. 6,076,578).
However, all of these prior art approaches to wheel design have disadvantages. First, prior multi-piece wheels designed for use with CTI systems only permit use of a single system, either non-integrated or integrated CTI, but not both. This limits the number of vehicle applications for the wheel to those compatible with that specific CTI system. Second, prior multi-piece wheels designed for use with CTI systems only permit use of a single system, either non-integrated or integrated CTI, but not both. This results in higher costs and additional complexity to develop, test, manufacture, and supply a wheel adapted for the CTI system of a specific vehicle. Third, multi-piece wheels constructed from steel prohibit the use of integrated CTI systems, as internal air passages cannot be made in the rim components due to the rim geometry. Fourth, multi-piece wheel designs that use fasteners to clamp the rim components together have limited space available on the wheel face for mounting integrated and non-integrated CTI valves. Fifth, multi-piece wheel designs with non-integrated CTI valves require the use of brackets to attach the CTI valve to the wheel. This moves the valve further outboard, making it more susceptible to damage. And, sixth, multi-piece wheel designs with non-integrated CTI valves require the use of brackets to attach the CTI valve to the wheel. This increases assembly time and adds to the complexity of mounting non-integrated CTI valves.
The instant invention resolves and avoids these difficulties by teaching wheel designs that allow both integrated and non-integrated Central Tire Inflation (CTI) systems to be installed on a single, light-weight wheel, without the need for a specialized manifold, adapter, or unique wheel to accommodate each specific system. The foregoing features and others of the inventive concept, as more fully described below, provide numerous advantages over the systems of prior art. To begin with, and most obviously, a wheel incorporating the teachings of our invention can accept either non-integrated or integrated CTI valves. This allows the wheels of the invention to be used on newer vehicles with integrated CTI systems, as well as on older vehicles with non-integrated (external) CTI systems. In addition, it is much simpler to assemble a non-integrated CTI valve to the wheel face since the valve mounts directly to the wheel and no brackets are required, unlike designs used with prior two-piece bolt-together wheels. Further, it is substantially less costly and complex to develop, test, manufacture, and supply a one wheel design that can be used on vehicles with different CTI systems, as opposed to multiple wheel designs. The numerous other advantages of our invention will become more apparent in view of the more detailed description and claims that follow.
USPTO Backgrounds
USPTO Backgrounds