Pumps – Condition responsive control of pump drive motor – Responsive to accumulation of pumped liquid in receiver
Patent
1984-10-12
1985-07-09
Freeh, William L.
Pumps
Condition responsive control of pump drive motor
Responsive to accumulation of pumped liquid in receiver
417 43, 417 63, 417411, 417540, F04B 4900, F04B 4906, F04B 3916, F04B 1100
Patent
active
045279535
ABSTRACT:
An improved pump unit for sampling air that operates at a constant air flow rate in the range of 5-5000 cc/min. having a filter for removing particles or vapors from the air stream, an air accumulator, a variable drive pump optionally with a bypass, an electric motor for driving the pump, an optional air reservoir, an orifice which creates a pressure drop in the air stream, an optional bypass for the orifice and a pressure switch connected in parallel to the orifice which monitors a change in the air pressure drop; the improvement in the pump is the use of a digital circuit electrically connected to the pressure switch and a closed loop control means electrically connected to the digital circuit and motor; a digital signal determines the open or closed position of the switch and the control means and allows current to flow or not flow to the motor driving the air pump to provide a constant flow of air through the unit; the pump unit is worn by a worker or is placed in a work area and at the termination of a period of time, such as a work day, the filter is removed and the contents collected are analyzed by conventional techniques such as gas chromatography to determine a level of exposure of the individual or the level of exposure of people working in that area.
REFERENCES:
patent: 4246788 (1981-01-01), Olin et al.
patent: 4384825 (1983-05-01), Thomas et al.
Baker W. Barry
Betsill Harry E.
E. I. Du Pont de Nemours and Company
Freeh William L.
Fricke Hilmar L.
LandOfFree
Pump unit for sampling air does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pump unit for sampling air, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pump unit for sampling air will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-907161