Abstract: A submersible pump assembly has a centrifugal pump with a number of stages, each of the stages having a rotatable impeller and a non rotating diffuser. The diffuser has vanes, each of the vanes curving radially inward from an outer end to an inner end. The vanes define vane passages between adjacent ones of the vanes through which well fluid flows. The vanes have thicknesses between inner and outer sides of each of the vanes that gradually increase from the outer ends toward the inner ends. At least one pocket is formed in each of the inner sides of each of the vanes. The pockets are open cavities to receive a portion of the well fluid flowing from the vane passages to the diffuser outlet.

Abstract: A submersible pump assembly has a centrifugal pump with a number of stages, each of the stages having a rotatable impeller and a non rotating diffuser. The diffuser has vanes, each of the vanes curving radially inward from an outer end to an inner end. The vanes define vane passages between adjacent ones of the vanes through which well fluid flows. The vanes have thicknesses between inner and outer sides of each of the vanes that gradually increase from the outer ends toward the inner ends. At least one pocket is formed in each of the inner sides of each of the vanes. The pockets are open cavities to receive a portion of the well fluid flowing from the vane passages to the diffuser outlet.

Abstract: An improved dual-sensor infrared intrusion alarm system includes a motion discriminator that renders the system responsive to only radiation-emanating objects that are moving through the system's scope of surveillance. A positive or negative sensor signal is developed depending on the relative amounts of radiation impinging on the sensors. A switching amplifier selectively discharges one of two capacitors depending on the polarity of the sensor signal. The voltages across the capacitors are coupled to the inputs of a voltage comparator and the capacitor recharge time constants are selected so that an alarm is indicated only when the length of the time interval between the occurrence of a sensor signal of a given polarity and the subsequent occurrence of a sensor signal of the opposite polarity is within prescribed limits, for example, two seconds.

Abstract: An electronic clock radio using a clock integrated circuit and a radio integrated circuit. A first energizing potential when applied to the NAP/SLEEP input connection of the clock circuit, causes the clock circuit to switch from a first electric state to a second electric state. After a selected interval of time, not greater than 60 minutes, the clock circuit switches from the second electric state to the first electric state. The radio, normally in an OFF state is placed in an ON state only upon receiving a second energizing potential applied to its input connection. A control circuit, having a manually operable switch with NAP and SLEEP positions and being responsive to the electric states of the clock circuit, connects this second energizing potential to the radio input only when:(i) the manually operable switch is in the NAP position and the clock circuit is the first electric state, or(ii) the manually operable switch is in the SLEEP position and the clock circuit is in the second electric state.