RFID sensor devices having drive elements

#The present subject matter relates to radio frequency identification (“RFID”) sensor devices. More particularly, the present subject matter relates to RFID sensor devices having components which are movable relative to each other upon an applied vibration.

#Electrically powered devices for sensing a material or condition are well known. Recently, sensors incorporating RFID technology have been proposed as a means for providing a sensing function at a relatively low power requirement. Exemplary sensors incorporating RFID technology are described in U.S. Patent Application Publication No. 2008/0135614 to Werner et al., which is incorporated herein by reference. Such devices typically include material which is sensitive to a substance (e.g., an analyte) and an antenna electrically connected to each other. When the antenna is energized, it sends a signal to a receiver device or controller which analyzes the signal. One or more of the electrical properties of the sensing material (typically its resistance) change when in the presence of the substance, which modifies the signal being transmitted by the antenna. The controller is programmed to analyze the modified signal and produce an output indicative of the presence of the substance in the vicinity of the sensing material and/or one or more properties of the substance.

#It may be desirable for the sensing material of the sensor to be temporarily and/or selectively isolated from the outside environment. Accordingly, sensors incorporating a mechanism for moving the sensor between a closed or inactive condition and an open or active condition are advantageous.

#FIG. 1 is a top plan view of an RFID-based sensor featuring selective rotational movement, with the sensor being shown in a closed condition;

#FIG. 2 is a top plan view of the RFID-based sensor of FIG. 1 in an open condition;

#FIG. 3 is a top plan view of an alternative RFID-based sensor featuring selective rotational movement, with the sensor being shown in a closed condition;

#The embodiments disclosed herein are exemplary only, and the subject matter described herein may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims.

#FIGS. 1 and 2 show an RFID-based device or sensor 10 according to the present disclosure. The sensor 10 comprises an upper or first layer 12 (shown in broken lines in FIGS. 1 and 2 for illustrative purposes) and a lower or second layer 14. The upper layer 12 includes at least one aperture 16 passing through the thickness of the upper layer 12. While the upper layer 12 is illustrated with a single aperture 16, it may include a plurality of apertures without departing from the scope of the present disclosure. As will be described in greater detail below, the first and/or second layers 12 and 14 are rotationally movable with respect to each other to reorient the aperture 16 between a closed or non-operational condition (FIG. 1) and an open or operational condition (FIG. 2).

#An RF communication chip 18, which may include an integrated circuit for controlling RF communication and other functions of the sensor 10, is associated with one of the layers. In the illustrated embodiment, the chip 18 is associated with the lower layer 14.