Venturi valve and control system

Abstract

Embodiments of the invention provide a venturi valve and control system for use in an indoor environment to regulate air flow. The venturi valve includes a substantially cylindrical pipe, a high pressure sensing assembly, a low pressure sensing assembly, a differential pressure transducer, and a damper assembly. The high pressure sensing assembly and the low pressure sensing assembly do not substantially impede air flow through the valve. A controller is connected to the differential pressure transducer and a damper actuator. The controller determines a current flow rate of air into the indoor environment and operates the damper actuator in order to provide a desired flow rate of air into the indoor environment.

The invention claimed is: 
     
       1. A venturi valve for use in an indoor critical environment to regulate air fluid flow, the venturi valve positioned in an exhaust a duct, the venturi valve comprising:
 a substantially cylindrical pipe tube including at least a first section having a first diameter perimeter and a second section having a second diameter perimeter, the first diameter perimeter being larger than the second diameter perimeter, wherein the first section is coupled to the second section by a third section that is defined by a reducing diameter perimeter; 
 a high pressure sensing assembly including a first pneumatic tube positioned around the first diameter perimeter, the first pneumatic tube coupled to a at least two first plurality of air fluid inlet ports, the at least two first plurality of air fluid inlet ports spaced around located in the first diameter perimeter to sense a first average static pressure at the first diameter perimeter; 
 a low pressure sensing assembly including a second pneumatic tube positioned around the second diameter, the second pneumatic tube coupled to a at least two second plurality of air fluid inlet ports, the at least two second plurality of air fluid inlet ports spaced around located in the second diameter perimeter to sense a second average static pressure at the second diameter perimeter; 
 a differential pressure transducer coupled to the high pressure sensing assembly and the low pressure sensing assembly, the differential pressure transducer generating a differential pressure signal based on the first average static pressure and the second average static pressure; 
 a damper assembly coupled to the substantially cylindrical pipe tube, the damper assembly including a damper and a damper actuator device; and 
 a controller connected to the differential pressure transducer and the damper actuator device, wherein the controller determining a current flow rate of air fluid into the indoor critical environment based on the differential pressure signal, the controller operating the damper actuator device based on the current flow rate in order to provide a desired flow rate of air fluid out of the indoor critical environment until the indoor critical environment is cleared through the exhaust duct and a pressure of the indoor critical environment is one of negative, neutral and positive relative to adjacent spaces. 
 
     
     
       2. The valve of  claim 1  wherein at least one of the first plurality of air inlet ports and the second plurality of air inlet ports each include at least six equally spaced inlet ports. 
     
     
       3. The valve of  claim 1  wherein at least one of the at least two first plurality of air fluid inlet ports and the at least two second plurality of air fluid inlet ports are coupled to an internal surface of the substantially cylindrical pipe tube in order to be surface flush. 
     
     
       4. The valve of  claim 1  wherein at least one of the at least two first plurality of air fluid inlet ports and the at least two second plurality of air fluid inlet ports minimally extend into an internal portion of the substantially cylindrical pipe duct. 
     
     
       5. The valve of  claim 1  wherein at least one of the at least two first plurality of air fluid inlet ports and the at least two second plurality of air fluid inlet ports do not bisect the substantially cylindrical pipe tube. 
     
     
       6. The valve of  claim 1  wherein at least one of the at least two first plurality of air fluid inlet ports and the at least two second plurality of air fluid inlet ports do not substantially impede air flow through the substantially cylindrical pipe tube. 
     
     
       7. The valve of  claim 1  wherein at least one of the at least two first plurality of air fluid inlet ports and the at least two second plurality of air fluid inlet ports extend up to about two inches into an internal portion of the substantially cylindrical pipe tube. 
     
     
       8. The valve of  claim 1  wherein the indoor environment includes at least one of a health care facility, a patient room, an isolation room, a procedure room, a pharmacy, an oncology room, a laboratory, an operating room, a research facility, a wet chemistry laboratory, a bio-containment room, a clean room, a life science facility, a vivarium, and an open bench laboratory. 
     
     
       9. The valve of  claim 1  wherein the venturi valve is used for one of supply air flow, exhaust air flow, hood air flow, return air flow, and bypass air flow. 
     
     
       10. The valve of  claim 1  and further comprising a cover surrounding the differential pressure transducer, the high pressure sensing assembly, and the low pressure sensing assembly. 
     
     
       11. The valve of  claim 1  and further comprising an actuator mounting bracket coupled to the substantially cylindrical pipe tube, the damper, and the damper actuator device. 
     
     
       12. The valve of  claim 1 , wherein the first section and the second section each have substantially constant diameters perimeters along a length thereof. 
     
     
       13. The valve of  claim 12 , wherein the substantially cylindrical pipe tube further includes a fourth section having an increasing diameter perimeter, and a fifth section having a diameter perimeter substantially equal to the first section, and wherein the fourth section is disposed between the second section and the fifth section. 
     
     
       14. A venturi valve for use in an indoor critical environment to regulate fluid flow, the venturi valve positioned in an exhaust a duct, the venturi valve comprising:
 a tube including at least a first section having a first perimeter and a second section having a second perimeter, the first perimeter being larger than the second perimeter, wherein the first section is coupled to the second section by a third section that is defined by a reducing perimeter;   a high pressure sensing assembly including at least two first fluid inlet ports, the at least two first fluid inlet ports located in the first perimeter to sense a first average static pressure at the first perimeter, said first perimeter having a first constant perimeter portion along a longitudinal axis of said venture valve, said high pressure sensing assembly being located in said first constant perimeter portion;   a low pressure sensing assembly including at least two second fluid inlet ports, the at least two second fluid inlet ports located in the second perimeter to sense a second average static pressure at the second perimeter, said second perimeter having a second constant perimeter portion along a longitudinal axis of said venture valve, said low pressure sensing assembly being located in said second constant perimeter portion;   a differential pressure transducer coupled to the high pressure sensing assembly and the low pressure sensing assembly, the differential pressure transducer generating a differential pressure signal based on the first average static pressure and the second average static pressure;   a damper assembly coupled to the tube, the damper assembly including a damper and a damper actuator device; and   a controller connected to the differential pressure transducer and the damper actuator device, wherein the controller determining a current flow rate of fluid into the indoor critical environment based on the differential pressure signal, the controller operating the damper actuator device based on the current flow rate in order to provide a desired flow rate of fluid out of the indoor critical environment until the indoor critical environment is cleared through the exhaust duct and a pressure of the indoor critical environment is one of negative, neutral and positive relative to adjacent spaces.    
     
     
       15. The valve of claim 14 wherein at least one of the at least two first fluid inlet ports and the at least two second fluid inlet ports extend up to about two inches into an internal portion of the tube.