Abstract: An automotive urea solution monitoring device is deployed in conjunction with the urea tank of a selective catalytic reduction vehicle. An RF signal of a constant frequency may be generated across a resonant circuit, which may be comprised of an inductor and a PCB trace capacitor, or the like. Electromagnetic radiation is propagated into the automotive urea solution in the urea tank. The conductivity and dielectric properties of the liquid change the impedance of the discrete/trace capacitor and or the discrete/trace inductor. These changes are proportional to ammonia content, temperature, and/or level of the automotive urea solution in the urea tank and are preferably detected by a microcontroller, or the like, and then transmitted to a selective catalytic reduction vehicle engine management system, or the like.

Abstract: An automotive urea solution monitoring device is deployed in conjunction with the urea tank of a selective catalytic reduction vehicle. An RF signal of a constant frequency may be generated across a resonant circuit, which may be comprised of an inductor and a PCB trace capacitor, or the like. Electromagnetic radiation is propagated into the automotive urea solution in the urea tank. The conductivity and dielectric properties of the liquid change the impedance of the discrete/trace capacitor and or the discrete/trace inductor. These changes are proportional to ammonia content, temperature, and/or level of the automotive urea solution in the urea tank and are preferably detected by a microcontroller, or the like, and then transmitted to a selective catalytic reduction vehicle engine management system, or the like.

Abstract: An automotive urea solution monitoring device is deployed in conjunction with the urea tank of a selective catalytic reduction vehicle. An RF signal of a constant frequency may be generated across a resonant circuit, which may be comprised of an inductor and a PCB trace capacitor, or the like. Electromagnetic radiation is propagated into the automotive urea solution in the urea tank. The conductivity and dielectric properties of the liquid change the impedance of the discrete/trace capacitor and or the discrete/trace inductor. These changes are proportional to ammonia content, temperature, and/or level of the automotive urea solution in the urea tank and are preferably detected by a microcontroller, or the like, and then transmitted to a selective catalytic reduction vehicle engine management system, or the like.

Abstract: A snap-in tire valve includes a valve body surrounded in part by a resilient element that forms an annular sealing surface configured to snap in place into a valve opening of a wheel. A tire pressure radio-frequency sending unit is mounted to the valve body, and a column extends from the sending unit. The region between the resilient element and the pressure sending unit defines an expansion volume that receives displaced portions of the resilient element during snap-in insertion of the valve body into a wheel opening, thereby facilitating insertion. Preferably the column defines a central passageway to facilitate insertion using standard insertion tools. In one version, two batteries are included in the sending unit, disposed on opposite sides of the column.

Abstract: A snap-in tire valve includes a valve body surrounded in part by a resilient element that forms an annular sealing surface configured to snap in place into a valve opening of a wheel. A tire pressure radio-frequency sending unit is mounted to the valve body, and a column extends from the sending unit. The region between the resilient element and the pressure sending unit defines an expansion volume that receives displaced portions of the resilient element during snap-in insertion of the valve body into a wheel opening, thereby facilitating insertion. Preferably the column defines a central passageway to facilitate insertion using standard insertion tools. In one version, two batteries are included in the sending unit, disposed on opposite sides of the column.