Pumps – Successive stages – Reciprocating rigid stages
Reexamination Certificate
2000-08-29
2001-12-11
Walberg, Teresa (Department: 3742)
Pumps
Successive stages
Reciprocating rigid stages
C062S117000
Reexamination Certificate
active
06328536
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to a compressor, which compresses fluid by use of reciprocating pistons.
BACKGROUND OF THE INVENTION
This invention relates generally to the technology of energy and liquid recycling and more particularly to an improved compressor apparatus for use in such technology. Such an improved compressor has great potential for use in vapor compression distillation and other applications in which low levels of vibration and steady flow output and constant pressure are desirable.
Vapor compression distillation is well known and understood in the broader field of distillation of liquids. In a vapor compression system, a liquid supply is at least partially evaporated. The vapor extracted is then adiabatically compressed thus elevating the temperature at which the vapor will recondense to some value higher than its original evaporative temperature. When the vapor recondenses it returns all of the latent heat that originally went into evaporating it back to the system The only energy placed into the system which is not recovered is the energy required to compress the vapor.
Vapor compression distillers generally make use of centrifugal compression, due to the simplicity, cost-effectiveness, and reasonable efficiency of the centrifugal process. However, as the distiller is scaled downward, centrifugal compression becomes more problematic. Efficiency falls off rapidly below 25 gallons of distillate per hour. As the output of the distiller decreases so too does the efficiency of the centrifugal compressor.
Compressors operating on the principle of reciprocation are more efficient in smaller sizes but generally are not suitable for vapor compression systems. Some of the problems associated with reciprocation are: 1) a piston-based compressor is more mechanically complicated and generally requires lubrication of the piston rings within the cylinder; 2) a piston-based compressor exhibits more severe wear characteristics; and 3) a piston-base compressor introduces pressure pulses due to the action of the piston.
There is no theoretical lower output limit to a vapor compression distillation unit. However, the practical problems associated with low output vapor compression which limit its feasibility are due to: 1) inefficiencies in heat transfer between the vapor and the incoming liquid; and 2) the compressor design. Low output vapor compression distillation is desirable for small incoming liquid streams such as commonly occur in residential waste collection systems. By distilling the water from a household waste stream and recycling it for use in watering the lawn, the garden or even as potable water great savings in waste management will be gained. Other uses certainly abound for systems operating at volumes less than 25 gallons per hour.
SUMMARY OF THE INVENTION
The invention in its broadest form resides in a compressor apparatus comprising a housing capable of being pressurized said housing having a plurality of chambers; a plurality of pistons, one slidably contained within each of said chambers for reciprocation; driving means for reciprocating said pistons within each chamber substantially axial direction without introducing lateral forces, means for introducing a vapor into a first of said chambers to be compressed by a first of said pistons; means for continuously pumping said compressed vapor from said first chamber successively through remaining of said plurality of chambers; means for removing said compressed vapor in a constant flow from a last of said chambers; and means for maintaining an interior of said housing at a pressure higher than ambient.
A preferred embodiment of the present invention provides a positive displacement compressor suitable for use in a vapor compression distiller characterized by an output volume of less than 25 gallons per hour.
Embodiments described hereinafter provide: (i) a compressor which produces a substantially steady output, (ii) a compressor that has the added ability to run with little or no lubrication in the piston cylinder, (iii) a compressor exhibiting minimal vibrational tendencies, (iv) a compressor suitable for use in a liquid waste disposal system, all of which may be adaptable to pump liquids.
As described hereinafter, there is provided a positive displacement compressor in which two pistons are arranged co-axially within co-axially aligned piston cylinders. These pistons being driven by a cam, and the piston strokes are timed accordingly to produce an even output flow. Lateral forces imposed by the cam on cam followers are absorbed by links or slides that impart purely axial loads on the pistons. Substantial elimination of the lateral forces eradicates side loads, resultant wear, and the necessity of piston ring lubrication. By timing the pistons to move in opposite directions, the accelerations associated with reversing each piston's vector of travel counteracts one another so as to minimize vibration.
In addition to maintaining a constant flow system characterized by negligible vibration, the alignment of the cylinders, combined with the valve sequencing and piston stroke timing, achieve a constant flow system
REFERENCES:
patent: 2425813 (1947-08-01), Kuntz
patent: 3771918 (1973-11-01), Winter
patent: 3861222 (1975-01-01), Braun et al.
patent: 4035243 (1977-07-01), Katz et al.
patent: 4105371 (1978-08-01), Savage et al.
patent: 4307997 (1981-12-01), Richards et al.
patent: 4308720 (1982-01-01), Brandstadter
patent: 4369633 (1983-01-01), Snyder
patent: 4390322 (1983-06-01), Budzich
patent: 4413474 (1983-11-01), Moscrip
patent: 4440601 (1984-04-01), Katz et al.
patent: 4510894 (1985-04-01), Williams
patent: 4536258 (1985-08-01), Huhta-Kolvisto
patent: 4561464 (1985-12-01), Frantz
patent: 4580414 (1986-04-01), Engelhard
patent: 4589257 (1986-05-01), Schaich
patent: 4718832 (1988-01-01), Takahashi
patent: 4734167 (1988-03-01), Goeldner
patent: 4787823 (1988-11-01), Hultman
patent: 4792289 (1988-12-01), Nieratschker
patent: 4832578 (1989-05-01), Putt
patent: 4878819 (1989-11-01), Bozoyan
patent: 4885017 (1989-12-01), Fleischmann
patent: 4909716 (1990-03-01), Orosz et al.
patent: 5483929 (1996-01-01), Kuhn et al.
patent: 5533358 (1996-07-01), Crandall et al.
patent: 5638736 (1997-06-01), Murakami et al.
patent: 5720177 (1998-02-01), Derrick et al.
patent: 5818131 (1998-10-01), Zhang
patent: 5983845 (1999-11-01), Yanagslawa
patent: 6015270 (2000-01-01), Roth
patent: 213478 (1941-02-01), None
patent: 714705 (1941-11-01), None
patent: 803938 (1936-10-01), None
patent: 263053 (1926-12-01), None
patent: 00/34656 (2000-06-01), None
Yeaple, Franklin D., Fluid Power Design Handbook, 1984, pp. 131-133, Marcel Dekker, Inc., New York, New York.
Cesari and McKenna LLP
Fastovsky Leonid
Ovation Products Corporation
Walberg Teresa
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