Abstract: A decoy mounting and movement system for mounting a hollow animal species decoy and for simulating life-like movement of the animal species between a rest position and a vertically pivoted position which simulates feeding by the animal species having a decoy mounting stake formed of an elongate upper stake section and an elongate lower stake section interconnected via an elongate vertical return spring capable of bending along its length to create an angle between the upper and lower stake sections, the upper stake section dimensioned for insertion into the hollow of the decoy through an opening in its underside in communication with the hollow of the decoy, wherein the fulcrum for vertical pivoting of the decoy is positioned at the lower end of the upper stake section and the ratio D?/D is less than 0.25, wherein D? is the distance between the underside of the decoy and the fulcrum for vertical pivoting, and D is the length of the upper stake section.

Abstract: A decoy mounting and movement system for mounting a hollow animal species decoy and for simulating life-like movement of the animal species between a rest position and a vertically pivoted position which simulates feeding by the animal species having a decoy mounting stake formed of an elongate upper stake section and an elongate lower stake section interconnected via an elongate vertical return spring capable of bending along its length to create an angle between the upper and lower stake sections, the upper stake section dimensioned for insertion into the hollow of the decoy through an opening in its underside in communication with the hollow of the decoy, wherein the fulcrum for vertical pivoting of the decoy is positioned at the lower end of the upper stake section and the ratio D?/D is less than 0.25, wherein D? is the distance between the underside of the decoy and the fulcrum for vertical pivoting, and D is the length of the upper stake section.

Abstract: A locking device for preventing relative rotation of pretorqued compression nuts used in face seal mechanical fittings includes an inner member having a cavity sized to slide onto and non-rotatably enclose the male or first nut of the fitting, an outer member having a first cavity sized to rotatably receive the inner member and a second cavity sized to slide onto and non-rotatably enclose the female or second nut of the fitting, and at least one set screw projecting inwardly through a threaded borehole in the outer member to non-rotatably engage and lock the inner member.

Abstract: An apparatus for collecting particulate material from a depository surface, such as a roadway, including a front-end collecting vehicle having a front-to-rear extending passageway. Mounted within the passageway is a first or front rotary rake member, a second rotary rake member behind the first rotary rake member, and a rotary brush member behind the second rotary rake member. Preferably mounted behind the vehicle frame is a conveyor mechanism for removing debris from the vehicular frame. Both rotary rake members include a plurality of interdigitating tines which are driven to move in the same forward direction so that the tines moving beneath the rotary axes are moving and collecting the debris rearwardly within the passageway. The rotary brush member is driven in the opposite rotary direction from the rake members to pick up the debris collected by the rake members and to force the debris rearwardly upon the conveyor mechanism.

Abstract: An explosive gas detector wherein power to a catalytic impedance element is held at a constant impedance level via a D.C., amplified, automatic bridge balancing circuit, and gas levels are indicated by an electrical meter connected between the output of a bridge and an adjustable level D.C. bias.

Abstract: An explosive gas detector employing an electrically conductive element which, when powered, changes temperature in the presence of an explosive gas, and a control circuit which senses the increases in temperature and decreases the power input to the element as an inverse function of changes in temperature of the element. The level of electrical power provided the element is indicative of the concentration of explosive gas present.

Abstract: An FM radar for the measurement of coal thickness wherein an FM transmitter is modulated by the combination of two signals, one, for example, being of a frequency of 100 Hz, and the other being of a frequency of 15 Hz. A horn-type antenna is used which is filled with a material having a dielectric constant approximating that of coal, the antenna being positioned flush against the coal.