Abstract: The disclosure of this invention includes a pressure swing adsorption oxygen concentrator having a plurality of zeolitic molecular sieve beds. The pressure and air flow in each bed is alternately charged between pressurizing and air flow in one direction to bleeding and counter flow in the opposite direction. Each time this change occurs, additional oxygen enriched gas from the pressurized bed to increase the incremental oxygen purity. These changes in this invention are initiated by a pressure sensitive transducer which detects a predetermined upper pressure limit. The air compressor drive includes a spring-biased swash plate which reciprocates the piston rods of reciprocating piston compressor pumps.

Abstract: A liquid meter including a freely rotatable impeller driven by a constant speed drive. Liquid to be metered is introduced as a flow against, and accelerated by, the impeller. The energy necessary to accelerate the liquid is monitored to determine liquid flow. Preferably, the impeller is driven through a magnetic coupling which facilitates isolation of at least large portions of the drive from the liquid flow. One preferred embodiment employs a pair of spring coupled shutters with one shutter being magnetically coupled to the impeller. The displacement of the spring is dependent on liquid flow with that displacement being determined by photoelectrically monitoring the relative positions of the shutters. The power necessary to maintain the drive at constant speed may also, or alternatively, be monitored to determine liquid flow.

Abstract: Fluid, such as milk, is conducted into the meter through an inlet passage and received in a fluid receptacle at least a portion of which is movable with at least a portion of the movement being in response to receipt of the fluid with the fluid then being expelled from the meter through a discharge passage. A sensor senses the movement of the movable portion caused by receipt of fluid in the fluid reservoir and, responsive thereto, provides an electrical signal indicative of the amount of fluid received, which electrical signal is coupled from the meter for utilization purposes. In one disclosed embodiment, a rotating wheel has fluid receptacles at the rim to receive the fluid conducted into the meter with the fluid being later (in the rotation of the wheel) dumped from the receptacle and expelled from the meter through the discharge passage.

Abstract: A valving system is disclosed that is useful for milking of animals such as cows. A stimulator, that includes one or more stimulator units each of which has biased elements, is releasably positioned on one or more teats of the animal to be milked and a warm liquid such as water is conducted through the stimulator units and ejected therefrom onto the associated teat or teats in order to induce milk let down. Each biased element has resilient gripping teeth to engage the teats of the animal to be stimulated. After the supply of liquid is terminated and the teat cups of a milking apparatus have been positioned on the animal, milk is withdrawn from the animal through a valve under the control of a control unit that has an input responsive to the temperature of the milk being withdrawn.