Abstract: A method and system for determining fluid flow rates through a motor driven pump controlled by a variable speed drive is disclosed. The variable speed motor drive is used to characterize a pump fluid flow for a plurality of motor torque values at a plurality of known pump speeds. These characterized pump flow rate/torque values/speed are stored and used to determine a pump fluid flow at a measured pump speed and motor torque by interpolating between the known characterized fluid flow/torque/speed values. In another aspect of the invention, the pump flow rate at a measured torque, at a specified characterizing speed value is determined by interpolating between known characterizing pump flow rates. The determined pump flow rates can then be used to determine pump flow rates at a measured speed by interpolating between corresponding speed values which bound the measured speed.

Abstract: An assembly for measuring fluid flow is provided having a base plate with an upstanding wall and a cut-out opening. A pivot shaft extends from the wall and a swinging arm is attached to the pivot shaft. At the lower end of the arm is a barrel shaft which supports a rotatable barrel. The base plate may be supported by legs and the assembly can then be positioned over an open stream of fluid. The arm is then swung down until the barrel enters the fluid. Alternatively, the assembly may be located above a top opening in a pipe containing a flowing stream of fluid. In this case, the arm and barrel will swing down through both the base plate cut-out opening and the pipe top opening. The moving fluid causes rotation of the barrel which is detected by a barrel rotation sensor. The sensor sends electronic signals to a signal processor which produces fluid velocity data. The arm may have an angular position sensor which will also deliver electronic signals to the signal processor.

Abstract: A transmitting electro-mechanical transducer is energized by electric pulses at a low frequency (typically several hertz to several kilohertz) to provide corresponding pulses of movement in the fluid. The fluid movement displaces a volume of the fluid in one direction and the motion of that fluid, when combined with the surrounding fluid, produces a fluid rotation which is sustained for a sufficient period of time, to be detected at a later time as an acoustic signal. A known distance downstream of the transmitting transducer, a receiving transducer detects the rotating volume of fluid. From the distance between the transmitting and receiving transducers and the time interval between their transmitted and detected signals, the fluid flow rate can be determined. The transmitting and receiving transducers can interchange their functions so that the difference in the time intervals is used to determine fluid flow rate.

Abstract: A fluid flow meter has a semi-conducting substrate and a number of integral flexible tines orientated across an aperture in the substrate to deflect in the direction of the fluid flow by an amount dependent on that fluid flow. Piezo-resistive regions are included on the respective tines to provide them with electrical characteristics which vary dependent on the degree of deflection. A monitor, operably coupled to the regions of the tines, is provided to monitor the changes in their electrical characteristics and to calculate the flow therefrom.

Abstract: An elevator for bulk material includes an elevator head that mounts a mass flow measuring device. The elevator head also supports the upper sprocket of the elevator. The elevator head is pivotable thereby permitting adjustment of the elevator chain tension without altering the spatial relationship between the elevator paddles, the top of the elevator head and the sensor surface of the mass flow measuring device.

Abstract: A hydrostatic drive system with an adjustable pump in the delivery flow has at least one consuming device connected to the pump. Associated with each consuming device are actuation devices that specify the direction of movement and the speed of movement. A control valve device controls the direction of movement and the speed of movement. The delivery flow of the pump can be adjusted to the hydraulic flow required by the actuated consuming devices. The hydrostatic drive system makes possible the operation of the consuming devices independently of the load and the operation of the consuming devices independently of the direction of the load, in a simple manner and with lower energy losses. Associated with each consuming device is a delivery flow sensor that measures the hydraulic flow discharged from the consuming device to a reservoir, and/or a delivery flow sensor that measures the hydraulic flow from a delivery line of the pump to the consuming device.

Abstract: A hydrostatic drive system with a pump and at least one consuming device that is connected to the pump can be actuated by a control valve. The control valve can be actuated as a function of an actuator that specifies a desired speed of movement and a direction of movement of the consuming device. The control valve in the center position, makes possible an unpressurized circulation of the pump. The control valve can be actuated electrically, and there is a sensor that measures the actual speed of movement of the consuming device. The control valve, the speed-of-movement sensor and the actuator are connected with an electronic control that controls the control valve as a function of the direction and speed of movement specified by the deflection of the actuator and of the actual speed of movement of the consuming device as measured by the speed-of-movement sensor. The speed-of-movement sensor may be a delivery flow sensor.

Abstract: A target flow meter has a target with a broad face attached to the free end of an elastic stalk. The stalk has at least a portion with an oblong cross section. A fixed end of the stalk is attached to a rigid support secured in the system to be measured with the broad face disposed transverse to the fluid flow. Strain gauges are affixed to the longer sides of the oblong portion. A temperature sensor may also be affixed there. The strain gauges are immersed in the fluid to be measured. Wires to the gauges and sensor pass through a fixed seal to the outside. They may be protected from the fluid by an impervious coating. By applying the strain gauges within the fluid, the system may be reduced in size, achieve greater sensitivity, and better temperature compensation.

Abstract: The indication that water is flowing in a fire protection sprinkler riser is often used as an initial indication that a fire has occurred in the protected building. The subject invention is an improved water flow switch, that uses a paddle with a reflective surface placed opposite an LED/Photodiode pair. When water begins to flow the force of the water against the paddle causes the paddle to rotate about a pivot. The pair are used to optically detect the rotation of the paddle. This approach eliminates many of the maintenance problems with the electro-mechanical flow switches currently available, as well as reducing the cost of manufacture. Furthermore, it makes possible the measurement of the rate of flow in the fire suppression sprinkler system, allowing the responding fire service to determine whether the fire is being controlled by the sprinkler system or not by observing the data at the fire alarm control panel, before fire fighters enter the fire compartment.

Abstract: A flow sensing assembly for detecting the presence of fluid flow includes a sensor body having a flow passage therethrough and a resilient blade having an end which is fixed relative to the sensor body and an end which is freely movable. The blade extends into and across the flow passage so that fluid flowing through the passage causes the free end of the blade to deflect in a downstream direction from a no-flow position to a flow position, and the free end of the blade returns to its no-flow position upon stoppage of flow. The flow sensing assembly also includes a detection device for detecting deflection of the blade and for producing a signal indicating the occurrence of fluid flow. A method of detecting the flow of fluid through a flow passage involves mounting a blade in the sensor body such that the blade extends into and across the flow passage whereby fluid flowing through the flow passage causes the free end of the blade to deflect in a downstream direction.