Abstract: A faucet-control device which enables users to control water flow in a basin fixture (10) by leaning against the front of the fixture (10) with a lower limb. Eight embodiments (A-H) are described. A normally-closed, electrically-controlled valve (16, 44, 46, or 62) controls water flow. A thin, flat, normally-open, momentary-contact, pressure-actuated mat switch (14) controls the valve (16, 44, 46, or 62). Any user in a normal stance may activate the mat switch (14) by applying a small pressure with a lower limb. In Embodiment A, activating the mat switch (14) opens the valve(s) (16), allowing water to flow. In Embodiment B, two stacked mat switches (14 and 14A) control a two-stage valve (44). In Embodiment C, a capacitive mat (50) enables the user to select continuously variable flow rates with a lower limb. A servo-drive circuit (48) converts variable capacitance from the capacitive mat (50) to an amplified current which drives a servo valve (46).

Abstract: A photovoltaic system controller particularly adapted for utilization with a photovoltaic power system including a photovoltaic array, system battery, load and, optionally, an auxiliary generator. The controller utilizes a microprocessor to monitor various parameters of the system and to perform system control functions. The microprocessor is provided with a plurality of setpoints corresponding to desired system parameters for utilization as reference points for the conducting of control functions. The setpoints are adapted to be easily field adjustable to cover a wide range of parameters. The controller is particularly suited for adaption to an entire spectrum of system designs merely by replacing the programmable memory component of the controller. The controller derives its power from a tap off the system battery and is designed to withstand the harsh environment associated with remote site locations. All of the control functions are temperature compensated.

Abstract: A power supply is provided for an electromechanical device of the type employing ultrasonic frequency vibratory energy for bonding materials. An automatic frequency control varies the output frequency of the power supply until the ratio of the maximum to minimum amplitudes of a standing wave produced in the mechanical vibratory member falls below a pre-set maximum. The frequency of the power supply is set by a voltage controlled variable frequency oscillator. A sweep generator produces a periodic voltage signal having a frequency substantially less than the frequency range of the voltage controlled oscillator.Means are provided for coupling the voltage signal from the sweep generator to the control input of the voltage controlled oscillator whenever the standing wave ratio exceeds a pre-set value, and for holding the last voltage signal received by the control input of the voltage controlled oscillator whenever the standing wave ratio is equal to or less than the pre-set value.