Abstract: A low-power radio-frequency (RF) receiver is characterized by a decreased current consumption over prior art RF receivers, such that the RF receiver may be used in control devices, such as battery-powered motorized window treatments and two-wire dimmer switches. The RF receiver uses an RF sub-sampling technique to check for the RF signals and then put the RF receiver to sleep for a sleep time that is longer than a packet length of a transmitted packet to thus conserve battery power and lengthen the lifetime of the batteries. The RF receiver compares detected RF energy to a detect threshold that may be increased to decrease the sensitivity of the RF receiver and increase the lifetime of the batteries. After detecting that an RF signal is being transmitted, the RF receiver is put to sleep for a snooze time period that is longer than the sleep time and just slightly shorter than the time between two consecutive transmitted packets to further conserve battery power.

Abstract: An angular momentum mass flowmeter for measuring the mass flowrate of a fluid stream includes a flowmeter housing having an inlet or upstream end for receiving the fluid stream and an outlet or downstream end for discharging the fluid stream. A rotatable impeller is provided for measuring the mass flowrate. A swirl cap is disposed downstream of the impeller for imparting angular momentum to the fluid stream passing thereover and for causing the angular momentum to rotate the impeller. A control valve, disposed intermediate the impeller and the swirl cap, modifies the flow area of the fluid stream passing over the swirl cap to regulate the angular momentum of the fluid stream.

Abstract: A Coriolis type flowmeter is described having 12 parallel flow tubes joined to a hub whose geometry is chosen to also perform the function of an inlet and outlet manifold. Plates are provided to interconnect and average the motion of the flow tubes as well as providing a platform for sensing Coriolis induced motion and inducing harmonic oscillations. Because of its symmetric geometry and balanced characteristics, the flowmeter is insensitive to vibration in any axis perpendicular to the axial axis of symmetry.

Abstract: Cleansing of a pyrometer lens is achieved by directing purge air spirally inward over the lens surface. The vortex formed by the spiral air flow is highly effective in removing contaminating matter from the lens surface. A light blocking or masking element is attached to the center of the lens where the purge air stagnates to prevent deposit of particles or other material on the center portion of the lens. This invention relates to a temperature sensing device and, more particularly, to an optical pyrometer and a method for effectively cleaning the same.