Abstract: An improved backflow preventing valve having an inlet passage opening to an intermediate chamber via an improved inlet check valve with the intermediate chamber opening to an outlet passage via an improved outlet check valve. A diaphragm chamber communicates with the intermediate chamber having a diaphragm therein dividing the diaphragm chamber into an inlet pressure portion opening into the inlet passage and an intermediate pressure portion opening to the intermediate chamber. An exhaust passage opening to atmosphere communicates with the intermediate pressure portion whereby fluid normally flows from the inlet passage through the intermediate chamber to the outlet passage but upon attempted backflow of the fluid, the improved check valves close with a positive closing action to prevent such backflow and, upon failure of the outlet check valve, the diaphragm flexes to open to vent such backflowing fluid out the exhaust passage.

Abstract: A water valve operating solenoid is disclosed having a unitary housing including a relatively thin plunger tube and a threaded nipple and formed of a non-magnetic plastic material. A coil bobbin having inner reinforcing sleeves is positioned around the plunger tube with a split sleeve bobbin cover positioned around the bobbin. Split washers are positioned at both ends to concentrate the flux path.

Abstract: Method and apparatus for sensing moisture by exposing water in a container to the atmosphere, sensing changes in the volume of the exposed water due to ambient weather conditions, controlling an electrical signal related to the sensed change and controlling the operation of an irrigation system, such as a plurality of solenoid-actuated pilot valves associated with sprinklers of the irrigation system, in response to the signal.

Abstract: Improvements in sprinkler systems having fluid under pressure flowing therethrough and a sprinkler head with a pop-up nozzle actuated by fluid pressure. An impeller is actuated by the fluid flow to rotate the nozzle and thus rotate the spray of fluid threfrom. A transmission is disposed between the impeller and the nozzle for transmitting rotation of the impeller to the nozzle. Means are provided for regulating the rate of rotation of the impeller, and then the nozzle, under varying volume flow of fluid being sprayed thereout. This may be accomplished by a substantially constant velocity of incoming fluid impinging on impeller blades.

Abstract: A water operated control apparatus and method for operating a controlled device is associated with moisture sensing apparatus for sensing the level of moisture available at a location and operating the controlled device in response thereto. Moisture sensing means is disposed at the location and is adapted to selectively pass air therethrough when the level of moisture at the location falls to a predetermined level, or prevent the passage of air therethrough when the level of moisture rises to a predetermined level. A housing is operatively connected to the sensing means and to a supply of water. A diaphragm is disposed in the housing in a manner forming a chamber therein, the interior of the chamber being in fluid communication with air passing through the sensing means.

Abstract: An automatic irrigation controller apparatus having a cam follower operated bank of pilot valves for operating selected pilot operated water valves throughout a watering or irrigation system is provided with a water powered means for receiving water under pressure from a source thereof and a member driven in a predetermined manner by the force of such water for driving a cam means to operate said cam followers via power transmission means between the water driven member and a cam shaft mounting said cam. A water piston is mounted in a cylinder with associated water valve means for selectively connecting the cylinder to a source of water under pressure and to a vent to provide a reciprocal movement for the piston, a return stroke for the piston being accomplished through the provision of a spring. A reciprocal piston movement is translated through a power transmission means including a drive ratchet wheel connected to the piston and a driven ratchet wheel connected to the cam shaft.

Abstract: A pressure control mechanism for an irrigation sprinkler having a rotatable riser with an orifice of predetermined shape with the riser sealed at the water inlet end thereof. In one embodiment, a stationary valve ring is snug-fit around the riser and circumferentially stationary with respect to the riser. The valve ring is spring biased against a shoulder on the riser at the inlet end and adapted to rise with the riser. The valve ring has an orifice which is congruent to the orifice of the riser whereby rotation of the riser with respect to the stationary valve ring regulates the flow of water through the valve orifice and the riser orifice to thereby regulate the flow of water through the sprinkler. In an alternative embodiment, a valve disc is secured to the inlet end of the riser and is circumferentially stationary with respect to the riser. The riser has a plug fixedly mounted at the inlet end and is keyed for limited rotation.

Abstract: An automatic irrigation controller apparatus having a cam follower operated bank of pilot valves for operating selected pilot operated water valves throughout a watering or irrigation system is provided with a water powered means for receiving water under pressure from a source thereof and a member driven in a predetermined manner by the force of such water for driving a cam means to operate said cam followers via power transmission means between the water driven member and a cam shaft mounting said cam. A water piston is mounted in a cylinder with associated water valve means for selectively connecting the cylinder to a source of water under pressure and to a vent to provide a reciprocal movement for the piston, a return stroke for the piston being accomplished through the provision of a spring. A reciprocal piston movement is translated through a power transmission means including a drive ratchet wheel connected to the piston and a driven ratchet wheel connected to the cam shaft.

Abstract: The hydraulic controller is for controlling the operation of a plurality of hydraulically controlled devices. Hydraulic fluid may be selectively distributed by the controller to various controlled hydraulic devices in a timed and predetermined sequence. The timing of the distribution of hydraulic fluid by the controller can be quickly and easily varied by various control knobs on the controller to thereby vary the timed operated period of the various machine operations controlled by such devices without affecting the timed operation of other machine operations. The controller is supplied with a source of hydraulic fluid under a generally constant pressure. Cam means are associated with each of a plurality of fluid flow distributing valves for operating such associated valve members in a predetermined sequence of valve positions upon advancement of the cam means relative thereto.