Pumps – With muffler acting on pump fluid
Patent
1998-01-30
2000-02-29
Freay, Charles G.
Pumps
With muffler acting on pump fluid
417 53, 417313, 41742314, 415119, F04B 5300
Patent
active
060301864
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a method and apparatus for minimising noise from air moving devices. In particular, the present invention pertains to a system for reducing noise from a fan filter unit in a clean room facility.
BACKGROUND OF THE INVENTION
It is common for a modern production and testing facility to control the particles in the air that circulates within a clean room facility in order to ensure the quality of its output. Whether be it wafer dies, compact discs or memory disk drives, effective fan filter units are needed to not only keep the particle contents within the clean room at acceptable levels but also to circulate the air which the workers breathe.
Such powerful fan filter units create excessive noise however. It is known that the insulation material are lined along the conduit or within the fan filter units to reduce the noise generate by the fan blowers. Over time, however, the particles or fiber from the insulation material are dislodged from the surface and contaminate the clean room facility.
The problem associated with the particle contents in clean room facility is exacerbated in confined space or enclosures such as a multi-story wafer fabrication plant. By confined space, the present invention envisages the height of the ceiling to be less than three meters. Because of the low height clearance, the noise from fan filter units is particularly pronounced.
OBJECT OF THE INVENTION
It is an object of the present invention to minimise the noise generated by fan filter units without increasing the particle counts of a clean room facility connected to such units.
It is another object of the present invention to minimise the noise generated by fan filter units without doing away with existing fan blower in a confined clean room facility.
SUMMARY OF THE INVENTION
The present invention is a system of geometric guides and baffles for directing and diffusing the external air drawn from a fan blower before distributing the flow evenly to the outlet a fan filter unit. This arrangement not only reduces the turbulence within a fan filter unit but also maintains the particle count of air drawn through the same system. Furthermore, the present invention is implemented in dimensions substantially similar to that of the fan blower. As such, the present invention minimises noise of a fan filter unit even in confined clean room facility.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a exploded, right side, perspective elevational view of the present invention being integrated as part of a fan filter unit (filter not shown).
FIG. 2 is a front, cross sectional elevational view of the system of geometric guides and baffles of the present invention together with filter of a fan filter unit.
FIG. 3 is a top, plan elevational view of section A--A in FIG. 2 highlighting the S shaped guide and curved baffle of the present invention.
FIG. 4 shows the locations in the fan filter units where the velocity of airflow were measured.
FIG. 5 is a chart comparing the average velocity of airflow of a fan filter unit with and without the present invention over a range of fan blower power supply (measured in Hz).
FIG. 6 is a chart comparing the noise level from a fan filter unit with and without the present invention and is measured at a location one meter directly below the outlet of the unit.
DESCRIPTION OF THE EMBODIMENT OF THE INVENTION
A method and apparatus for minimising noise from a fan filter unit is described. In the following description, numerous specific details are set forth such as guides and baffles, etc. in order to provide a thorough understanding of the present invention. In other instances, well-known parts such as the motors for the fan blower and ducts connected to the fan filter units are not shown in order not to obscure the present invention.
FIG. 1 is a exploded, right side, perspective elevational view of the present invention being integrated as part of a fan filter unit 10 (filter not shown). The fan filter unit comprises a fan blower 12 disposed withi
REFERENCES:
patent: 1938801 (1933-12-01), Bourne et al.
patent: 2330938 (1943-10-01), Williams
patent: 3113634 (1963-12-01), Watters
patent: 4560395 (1985-12-01), Davis
patent: 4768424 (1988-09-01), Frenkler et al.
patent: 5346362 (1994-09-01), Bonner et al.
patent: 5462482 (1995-10-01), Grimes
patent: 5470363 (1995-11-01), Leader et al.
patent: 5601400 (1997-02-01), Kondo et al.
Freay Charles G.
Kyodo-Allied Industries PTE, Ltd.
Tyler Cheryl J.
LandOfFree
Method and apparatus for minimizing noise from fan filter unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for minimizing noise from fan filter unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for minimizing noise from fan filter unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-677012