Abstract: A capacitance probe extends into a container for material which increases the capacitance between the probe and the container when the material contacts the probe. A fixed RF voltage is supplied to the base of a transistor in an electronic translator having a capacitor between the probe and the transistor's emitter. A first diode conducts between the base and RF ground. A second diode conducts between the emitter and the base. A small-value capacitor is connected between an ungrounded DC supply terminal and the probe. A third diode conducts variable DC to the transistor's collector from a variable DC signal line supplied with DC for the DC terminal through a resistor. A comparator has a first input connected to the line and a second input connected to a reference voltage. The comparator's output is adapted to energize an output signal and a relay when the DC signal on the line drops below the reference voltage.

Abstract: The shaft seal construction is employed in a bin level indicator between the housing and the rotatable shaft thereof. The housing has an enlarged bore therein concentric with the shaft. A composite pressure sealing ring is disposed in sealing relation between the shaft and the bore. Such ring has a rubber-like pressure sealing ring member facing forwardly and a metal backing ring member behind the rubber-like ring member and preferably bonded thereto. The rubber-like ring member has a peripheral surface in sealing engagement with the bore, and a forwardly projecting annular sealing lip in rotary sealing engagement with the shaft. The metal backing ring member has a peripheral surface compressibly engaging the bore with an interference fit therebetween. A rubber-like vacuum sealing ring is disposed behind the metal backing ring member and is provided with a first frusto-conical sealing lip, engaging the backing ring member, and a second annular sealing lip in sealing engagement with the shaft.

Abstract: A level control device is disclosed comprising a paddle on a rotary shaft projecting from a housing, a carrier disc coupled to the shaft and supporting a plurality of torque-transmitting levers having first arms engageable by drive pins or an apertured drive disc on an output shaft of an electric motor, an axially movable control plate biased toward the carrier by spring means which also cause the control plate to rotate with the carrier, the levers having second arms disposed between the carrier and the control plate for moving the control plate away from the carrier when the driving torque transmitted by the first arms increases due to increasing drag on the paddle caused by rising granular material coming into contact with the paddle, and a control switch operable by the movement of the control plate away from the carrier. The position of the switch is adjustable to provide a sensitivity adjustment. A slip clutch may be provided between the carrier and the paddle shaft.

Abstract: A blast aerator for fluidizing granular material, comprising a container connected to a supply of compressed air, an aerator valve casing having a diaphragm chamber therein, a flexible resilient diaphragm dividing the chamber into first and second portions, a conduit connected between the container and the first portion, an air blast outlet connected to an outlet port in the first portion, the diaphragm including a valve member initially closing the port by the resilience of the diaphragm, a bleed opening in the diaphragm for pressurizing the second portion when the first portion is pressurized, and a control valve for opening and closing a vent outlet from the second portion, the control valve when closed allowing pressurization of the second portion, and, when open, exhausting the pressure therefrom, whereupon the pressure in the first portion opens the valve member and quickly releases the compressed air from the container to produce an air blast through the outlet.

Abstract: The level winding reel mechanism comprises a frame, a winding reel rotatably mounted on the frame, a line connected to the reel and adapted to be wound thereon, and a pulley rotatably mounted on the frame for guiding the line to the reel, the pulley having a peripheral groove therein for receiving the line, the reel having a stepped hub comprising first and second cylindrical portions having first and second different diameters with an annular shoulder between the first and second portions, the first diameter being less than the second diameter by an amount corresponding generally with the diameter of the line, the reel having first and second end flanges projecting radially from the ends of the first and second portions of the hub, the hub having anchor means therein for anchoring one end of the line, the first portion of the hub having an entry hole therein for receiving the line, the entry hole being adjacent the shoulder, the pulley having its peripheral groove in alignment with a point on the first porti

Abstract: Apparatus for monitoring the motion of a movable element, such as a rotatable shaft, comprising sensor means for producing a series of repetitive pulses in response to the motion of the movable element, ramp generator means for producing an increasing ramp signal, the ramp generator means including means for resetting the ramp signal to a starting level in response to each of the pulses, level detector means operable in response to the increase of the ramp signal above a predetermined level, and control means for performing a control function in response to the operation of the level detector means.

Abstract: A vibratory system is provided on a wall member of a receptacle. The vibratory system comprises inner and outer rod elements projecting transversely from the inner and outer sides of the wall member and secured thereto, as by an internal screw stud with the axes of the rod members substantially aligned. Vibrations are induced in the outer rod element by an electromagnet having a coil which is supplied with low frequency electrical pulses. The magnitude of such vibrations is sensed by sensing the electrical signals induced in the coil due to such vibrations. A biasing magnetic flux is produced between the electromagnet and the outer rod element so that the vibrations produce variations in the magnetic flux. The electrical pulses supplied to the coil are at a substantially lower frequency than the natural vibration frequency of the outer rod element.