Patent Application
20110165840
This invention generally relates to antennas associated with rotating components, and more particularly, to translating telemetry stationary antennas.
Rotating shafts and rotors are utilized in many machines, including motors, generators, and turbines to efficiently transmit kinetic energy between components within or external to the machine. Typically, the rotors associated with a machine rotate about an axis relative to a stationary frame of reference. The stationary frame of reference may be defined as the non-rotating part machine. In some cases, particularly in electrical motors and generators, an electrical connection must be made between the stationary part of the machine and the rotating part of the machine. Direct current electrical motors and generators, for example, utilize brushes to electrically connect and commutate stationary current sources or sinks with electrical windings on the rotor.
Slip rings are also utilized for establishing a connection to a rotor. A slip ring consists of a conductive circle or band mounted on a rotor, but electrically insulated from the rotor and other slip rings. Electrical connections from components on the rotor may be connected to the slip rings, and stationary contacts or brushes can rub against rings to transfer electrical power or signals to and from the stationary part of the machine.
In certain machines, however, slip rings, brushes, and mechanical contacts can wear out, and they may not be practical in terms of durability and reliability. Furthermore, rubbing mechanical contacts against a slip ring may effectively degrade signals and may induce unwanted noise and/or impose limits in the signal bandwidth such that communications between the rotor and stationary part of the machine is compromised.
To overcome such limitations, rotary antenna systems have been proposed for providing non-contact electrical communications (telemetry) between a rotating and stationary part of a machine. Rotary antennas typically consist of a pair of circular “hoop”-shaped and concentrically aligned antennas: one attached to the rotating part, and one attached to the stationary part of the machine. The rotating antenna and the stationary typically must be carefully aligned both axially and radially with a minimum air gap separation for suitable coupling between antennas. Therefore, heavy and complex support structures are typically utilized to mount the stationary antenna to the stationary part of the machine. Manual alignment of the stationary antenna with respect to the rotating antenna is often a time consuming and tedious task, requiring multi-dimensional adjustments of the stationary antenna. Furthermore, if the rotor translates with respect to the stationary frame (due to expansion, contraction, or other factors), the antennas may become misaligned during operation and communications and or inductive power transfer between the antennas may be interrupted.
Therefore, a need remains for improved systems and methods for a translating telemetry stationary antenna.
Some or all of the above needs may be addressed by certain embodiments of the invention. Certain embodiments of the invention may include systems and methods for a translating telemetry stationary antenna.
According to an exemplary embodiment of the invention, a method for mounting a stationary antenna with respect to a rotor antenna associated with a rotating component is provided. The method includes mounting a stationary antenna to an inner circumference of a support frame, mounting a plurality of radial air bearings to the support frame for maintaining radial alignment of the stationary antenna with respect to the rotor antenna, and mounting a plurality of axial air bearings to the support frame for maintaining axial alignment of the stationary antenna with respect to the rotor antenna.
According to another exemplary embodiment, a method of communication between a rotor antenna mounted to a rotating component and a stationary antenna is provided. The method includes mounting a stationary antenna to at least a portion of an inner circumference of a support frame, where radial alignment and axial alignment of the stationary antenna with respect to the rotor antenna are maintained by a plurality of air bearings. The method also includes transferring a signal between the stationary antenna and the rotor antenna.
According to another exemplary embodiment, an apparatus is provided for communication with a rotor antenna. The apparatus includes a support frame and a stationary antenna mounted to a support frame. The stationary antenna is maintained in axial alignment and radial alignment with respect to the rotor antenna by a plurality of air bearings, and the stationary antenna is operable to communicate with the stationary antenna.
Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. Other embodiments and aspects can be understood with reference to the following detailed description, accompanying drawings, and claims.
Reference will now be made to the accompanying tables and drawings, which are not necessarily drawn to scale, and wherein:
Embodiments of the invention will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. The term “exemplary” as used throughout this document is defined to mean “example.”
Certain embodiments of the invention may enable communication between a rotating and a stationary antenna. According to certain exemplary embodiments of the invention, a stationary antenna may maintain axial and radial self-alignment with a corresponding rotating antenna attached to a rotor.
According to exemplary embodiments of the invention, various air bearings and floating support systems may be utilized to maintain alignment of a stationary antenna with respect to a rotating antenna. Exemplary systems and methods will be described with reference to accompanying figures, with the exception of
In contrast,
According to exemplary embodiments of the invention, the stationary antenna 212 may include a top-half stationary antenna section 214 and a bottom-half stationary antenna section 216. According to exemplary embodiments of the invention, the stationary antenna 212 may be mounted to the support frame 202, and the combined assembly 202, 212 may provide axial and radial alignment of the stationary antenna 212 with the rotor antenna 218 via the air bearings 208, 210. For example, the support frame 202 may house three or more radial bearings 210, positioned and mounted equidistant around the inner circumference of the support frame 202. The radial bearings 210 may communicate radially with a mating surface on the rotor 222, and may facilitate radial alignment of the stationary antenna 212 with the rotor antenna 218. When air is forced through the radial bearings 210, the rotor 222 and rotor antenna 218 may rotate freely about the axis of rotation 224 in relation to the combined support frame 202 and the stationary antenna 212. This exemplary embodiment also allows, for example, an air delivery system to be hooked to the air bearings 209210 on the support frame 202.
According to an exemplary embodiment of the invention, the support frame 202 may also include one or more axial bearings 208. The axial bearings 208 may be operable to maintain axial alignment of the stationary antenna 212 with the rotor antenna 218. The axial bearings 208 may communicate axially with a mating surface associated with the rotor 222. For example, the axial bearings 208 may communicate with an axial bearing flange 220 attached to the rotor 222. When air is forced through the axial bearings 208, the rotor 222 and rotor antenna 218 may rotate freely about the axis of rotation 224 in relation to the combined support frame 202 and the stationary antenna 212, while at the same time, the axial alignment of the stationary antenna 212 may be maintained with the rotor antenna 218.
According to exemplary embodiments of the invention, the translating telemetry stationary antenna system 200 may be utilized for communicating signals between the rotating antenna and the stationary antenna 212. For example, various measurement and/or control devices including transducers, sensors, strain gauges, accelerometers, tachometers etc., may be attached to the rotor 222 for measuring various parameters associated with the machine. The measurement and/or control devices may be attached to the rotor 222, and their power ports may be connected to a rotor antenna 218 in communication with a stationary antenna 212. In this exemplary configuration, the translating telemetry stationary antenna system 200 may act as a power transmission device to couple power from the stationary antenna 212 to the rotor antenna 218 for powering the measurement and/or control devices attached to the rotor 222. A combined or separate translating telemetry stationary antenna system 200 may also be utilized to transmit signals from the measurement and/or control devices attached to the rotor 222 via the rotor antenna 218 to a stationary receiver in communication with the stationary antenna 212. For example, in one embodiment, the stationary antenna 212 may include one antenna element operable to transmit power to a corresponding dedicated (power) rotor antenna 218, and the same stationary antenna 212 may also include another antenna element operable to receive signals from a corresponding dedicated (signal) rotor antenna 218. In another embodiment, the power and signal antennas may be combined.
According to other exemplary embodiments of the invention, various combinations and configurations of the air bearing placements and shapes may be utilized to reduce the cost, weight, and complexity of the translating telemetry stationary antenna system 200. For example,
An exemplary method 400 for mounting a translating telemetry stationary antenna system 200 will now be described with reference to the flowchart of
An exemplary method 500 for utilizing the translating telemetry stationary antenna system 200 to communicate between a stationary component and a rotating component will now be described with reference to the flowchart of
Accordingly, exemplary embodiments of the invention can provide the technical effects of creating certain systems and methods that provide for signal energy (including power) to be coupled between a pair of non-contacting antennas, where one antenna may be stationary, and the other antenna may be attached to a rotating component. Exemplary embodiments of the invention can provide the further technical effects of providing systems and methods for reducing the weight, cost, and/or complexity associated with a telemetry system. Furthermore, exemplary embodiments of the invention can provide the technical effects of maintaining axial and radial alignment between a stationary antenna 212 and a rotor antenna 218, as the rotor 222 translates with respect to a stationary part of an associated machine. Exemplary embodiments of the invention can also provide the further technical effects of providing systems and methods for electrically isolating the stationary antenna 212 from the rotating antenna 218, thereby improving the data acquisition signal quality by eliminating a ground path between sensors and the data acquisition system.
As desired, embodiments of the invention may include the translating telemetry stationary antenna system 200 with more or less of the components illustrated in
The invention is described above with reference to block and flow diagrams of systems, methods, and/or apparatuses according to exemplary embodiments of the invention. It will be understood that some blocks of the block diagrams and flow diagrams may not necessarily need to be performed in the order presented, or may not necessarily need to be performed at all, according to some embodiments of the invention.
While the invention has been described in connection with what is presently considered to be the most practical and various embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
