Abstract: A choke assembly for provision onto an oven door to seal radio frequency (RF) energy within the oven when the door is closed may include a capacitive coupling element and an inductive tuning element. The capacitive coupling element may include a plurality of tabs each having a first width. The inductive tuning element may include a plurality of projections bent relative to the capacitive coupling elements at a right angle, the projections each having a second width that is smaller than the first width.

Abstract: An adjustable height landscape light fixture includes an outer cylindrical body portion having a upper threaded segment and an inner riser portion telescopically mounted in the outer cylindrical body portion. A collet surrounds the inner riser portion. A threaded cap is screwed over the upper threaded segment of the cylindrical body portion. The threaded cap is configured to squeeze the collet against the inner riser portion to fix and un-fix a predetermined longitudinal position of the inner riser portion relative to the outer cylindrical body portion and provide a substantially water impervious seal between the threaded cap and the inner riser portion. An incandescent or LED upper light portion is mounted to an upper end of the inner riser portion.

Abstract: An adjustable height landscape light fixture includes an outer cylindrical body portion having a upper threaded segment and an inner riser portion telescopically mounted in the outer cylindrical body portion. A collet surrounds the inner riser portion. A threaded cap is screwed over the upper threaded segment of the cylindrical body portion. The threaded cap is configured to squeeze the collet against the inner riser portion to fix and un-fix a predetermined longitudinal position of the inner riser portion relative to the outer cylindrical body portion and provide a substantially water impervious seal between the threaded cap and the inner riser portion. An incandescent or LED upper light portion is mounted to an upper end of the inner riser portion.

Abstract: A sprinkler includes a riser having a lower end for receiving a pressurized fluid and a nozzle that is mounted at an upper end of the riser for rotation about an axis. A turbine is mounted for rotation inside the riser. A drive mechanism connects the turbine to the nozzle so that rotation of the turbine by the pressurized fluid rotates the nozzle. The sprinkler includes mechanisms for preventing over-spinning of the turbine when the pressurized fluid is air or a mixture of air and water. Damage to the turbine drive shaft or its bearings due to over-spinning of the turbine is thereby avoided. In one version of the sprinkler, the over-spinning prevention mechanism applies a brake force to the turbine. In another version of the sprinkler, the over-spinning prevention mechanism re-directs air or a mixture of water and air around the turbine.

Abstract: A sprinkler includes a riser having a lower end for receiving a pressurized fluid and a nozzle that is mounted at an upper end of the riser for rotation about an axis. A turbine is mounted for rotation inside the riser. A drive mechanism connects the turbine to the nozzle so that rotation of the turbine by the pressurized fluid rotates the nozzle. The sprinkler includes mechanisms for preventing over-spinning of the turbine when the pressurized fluid is air or a mixture of air and water. Damage to the turbine drive shaft or its bearings due to over-spinning of the turbine is thereby avoided. In one version of the sprinkler, the over-spinning prevention mechanism applies a brake force to the turbine. In another version of the sprinkler, the over-spinning prevention mechanism re-directs air or a mixture of water and air around the turbine.

Abstract: A sprinkler unit of the type that includes an impact drive sprinkler vertically reciprocable inside a subterranean can or case is modified to incorporate a modern pop-up rotor-type sprinkler. The rotor-type sprinkler has a lower retraction spring retainer half-way up its outer riser and a shortened retraction spring. A cylindrical adaptor sleeve surrounds the riser and has its upper end screwed into the upper end cap of the rotor-type sprinkler. The impact drive sprinkler and its attached riser assembly are unscrewed from the subterranean mounting case. Thereafter, a lower male threaded end of the adaptor sleeve is screwed into a female threaded segment at the junction of the lower and upper sections of the cylindrical mounting case. A ring-shaped protective cover plate with a pair of spring retention arms is rotatably mounted to the top end of the rotor-type sprinkler to fill the gap between the sprinkler and the upper curved lip of the cylindrical mounting case.

Abstract: A diaphragm-type control valve for irrigation systems has an outer clam-shell housing that encloses a vertically reciprocable diaphragm assembly. A primary valve seat inside the housing is engaged and disengaged by a seal on the underside of the diaphragm to open and close the valve by connecting and disconnecting its inlet and outlet passages. Pressurized water from a lower inlet chamber of the valve travels through a small metering orifice in the center of the diaphragm assembly to an upper pressure control chamber above a flexible membrane of the diaphragm assembly. A solenoid actuated pilot valve is operatively coupled to the upper pressure control chamber for venting pressurized water therefrom to permit the diaphragm assembly to move upwardly to open the valve. A filter screen is mounted to the underside of the diaphragm assembly to prevent debris from clogging the metering orifice, clogging the small passages of the pilot valve, or fouling the solenoid.

Abstract: A cleaning cycle generator for an irrigation system having a programmable irrigation controller. When the irrigation controller terminates an on cycle, the cleaning cycle generator of the present invention will initiate a time delay after which it will turn the sprinklers completely on for a timed period. The sprinklers will then be turned off to complete the remainder of the off cycle. The present invention is particularly advantageous in pressure regulated irrigation valves where particles in the water can become trapped between valve seat surfaces that are in close proximity due to the pressure regulation. Leaking throughout the lengthy off cycle of the irrigation system is prevented by flushing out particles while the valve is in the completely open, unregulated state.

Abstract: A sprinkler unit comprises a tubular housing having an inlet for connecting to a source of water, a tubular riser telescopically reciprocally mounted in the tubular housing and moveable from a retracted position within the housing to an extended position from the housing, the riser having an outlet having a nozzle for distributing a stream of water outward from the housing, a passage connecting the inlet to the outlet, a retraction spring normally biasing the riser to the retracted position, and a shock absorbing coating on the retracting spring for absorbing the shock of movement of the riser to the extended position.

Abstract: A sprinkler unit comprises a housing having an inlet for connecting to a source of water, a rotating head mounted in an upper end of the housing and including an outlet nozzle for distributing a stream of water outward from the housing, a drive assembly including a turbine and a reduction gear drive train connecting the turbine to the head for rotating the head, the drive train having a gap for intermittently interrupting the drive for causing the head to intermittently pause during rotation thereof.

Abstract: In a self-propelled irrigation system, a wheeled support assembly is specifically adaptable for use in controlling the movement of an articulated or corner boom with respect to the rest of the system, the wheeled support assembly being characterized in that the wheels are self-aligning along a desired path of travel in accordance with the angular relationship between the corner boom and rest of the irrigation system. The invention has particular application to center pivot types of irrigation systems for the purpose of uniformly irrigating the corner areas of a generally rectangular field outside of the circular path of travel of the irrigation system.

Abstract: The present invention discloses an improved center pivot for a self-propelled center pivot irrigation system. The preferred embodiment is characterized by a vertical pivot pipe supported for rotational movement at both the upper and lower extremities thereof. Additionally, the gasket assembly providing leak-proof rotational movement of the pivot pipe relative to a fixed liquid supply pipe is characterized by a slideable casing which can be moved from a normal operating position wherein the fixed supply pipe and the rotating pivot pipe are bridged by the casing with gaskets disposed between mating surfaces and a second non-bridged position wherein the gaskets are removable so as to allow replacement of worn gaskets without moving or removing any of the major pipe components of the sprinkler system.

Abstract: The present invention discloses an improvement in angularity sensors employed in center pivot irrigation systems. A center pivot irrigation system has a plurality of self-propelled articulating span units mounting interconnected sections of water carrying conduit, each span unit has motor means and motor control means for regulating the operation of the associated motor means to maintain the span units in a pre-determined relative alignment in a vertical plane revolving about a vertical line at the center pivot of the system. The control means has angularlity sensor means which is connected between span units for sensing in a substantially horizontal plane changes in angularity between the span units relative to the desired revovling vertical plane.

Abstract: A method and apparatus for operating a center pivot irrigation system including a plurality of span units, each having a drive carriage having a hydraulically driven motor means for operating associated carriage wheels in response to hydraulic fluid supplied thereto under pressure through hydraulic fluid lines from a source thereof, is operated by supplying hydraulic fluid at a selectable value of constant volume fluid flow to the system to drive the system at a selectable average speed about its center pivot, the flow rate of fluid to individual motor means of individual span units which are ahead or behind of a predetermined relative alignment with the other span units being varied in response to changes in angularity sensed between adjacent span units in both forward and backward directions relative to the direction of travel of the system about its center pivot while the constant volume fluid flow through the system is being maintained at a selectable constant flow rate.

Abstract: A self-propelled center pivot irrigation system has individual span units each one of which has at least one or more fluid conduits, and at least one or more power frames for propelling the span unit, each power frame has at least one or more drive wheels, a drive motor, and transmission means connecting the drive motor to the drive wheels to transmit power from the drive motor to the drive wheels, the transmission means has an input drive gear, intermediate planetary gear speed reduction means and an output shaft for connection between the drive motor output shaft and the power frame drive wheels to provide a low friction, speed reducing, torque increasing drive for the power frame drive wheels from the drive motor.