Liquified gas dry-cleaning machine with improved agitation system

Information

  • Patent Grant
  • 6360392
  • Patent Number
    6,360,392
  • Date Filed
    Wednesday, June 23, 1999
    25 years ago
  • Date Issued
    Tuesday, March 26, 2002
    22 years ago
Abstract
A liquified gas dry-cleaning system having a pressure vessel for containing a liquid wash bath and a perforated basket rotatably supported within the pressure vessel for containing items during cleaning. For enhancing cleaning and the removal of solid particulate matter on the items to be cleaned, the basket has a plurality of radial mixing baffles fixed to the periphery of the rotary basket and a plurality of gas jet manifolds fixed to the baffles which are operable for directing pressurized jet streams of liquified gas into the basket for agitating the contained items and wash bath simultaneously with physical agitation by the mixing baffles. The dry-cleaning system has a successively operated air purge cycle prior to a dry cleaning cycle, which includes sealing the pressure chamber, introducing a gaseous form of the liquified gas which makes up the wash bath, rotating the basket so that items contained therein are turned and flexed to release at least a portion of any contained air therein, and venting the introduced gas and released air from the pressure vessel.
Description




FIELD OF THE INVENTION




The present invention relates to dry-cleaning systems and, more particularly, to a liquified gas dry-cleaning system having a cleaning vessel with improved means for agitating contained items for enhanced and more efficient cleaning.




BACKGROUND OF THE INVENTION




Known dry-cleaning processes consist of a wash, rinse, and draining/drying cycle with solvent recovery. During the dry-cleaning process, items, such as garments, are loaded into a basket disposed within a vessel and immersed in a dry-cleaning solvent that is pumped into the vessel from a base tank. Conventional dry-cleaning solvents include perchloroethylene (PCE), petroleum-based or Stoddard solvents, CFC-113, and 1,1,1-trichloroethane, all of which are generally aided by a detergent.




The use of these conventional solvents, however, poses a number of health and safety risks as well as being environmentally hazardous. For example, halogenated solvents are known to be environmentally unfriendly, and at least one of these solvents, PCE, is a suspected carcinogen. Known petroleum-based solvents are flammable and can contribute to the production of smog. Accordingly, dry-cleaning systems which utilize dense phase fluids, such as liquid carbon dioxide, as a cleaning medium have been developed. An apparatus and method for employing liquid carbon dioxide as the dry-cleaning solvent is disclosed in U.S. Pat. No. 5,467,492, entitled “Dry-Cleaning Garments Using Liquid Carbon Dioxide Under Agitation As Cleaning Medium”. A similar dry-cleaning apparatus is also disclosed in U.S. Pat. No. 5,651,276.




These systems pose a number of other problems, particularly in relation to the high operating pressures necessary for maintaining the gas in a liquid state. Specifically, the cleaning vessel in a liquid carbon dioxide dry-cleaning system operates at between 700-850 psi under ambient temperature conditions. The dry-cleaning solvent functions to dissolve the soluble soils on the item. The insoluble soils, however, must be physically dislodged from the item, which typically required agitation of the items in the cleaning solvent during the wash and rinse cycles.




In dry-cleaning systems that utilize liquified gas as a cleaning solvent, it has been particularly difficult to effect agitation sufficient to clean items of extremely fine unsoluble soils, such as dirt or like particles three microns and less in size. Because of the high operating pressures under which the liquified gas must be maintained, care also must be taken to prevent damage to the goods from pressurized streams of liquified gas introduced into the cleaning vessel.




Furthermore, in liquified gas dry-cleaning systems it is necessary that the liquified gas be completely removed from the cleaned items, vaporized to separate the contaminants and foreign particulate matter, and reliquified for re-circulation through the system. The cycle time for such processing can be lengthy, thereby increasing the operating cost. The presence of air in the liquid carbon dioxide cleaning solvent, such as air that enters the cleaning solvent from items introduced into the system for cleaning, also can adversely affect the cleaning process. Heretofore methods of removing or venting such air have not been effective.




Accordingly, a need exists for an improved dry-cleaning system, and in particular, an improved liquified gas dry-cleaning system.




OBJECTS AND SUMMARY OF THE INVENTION




It is an object of the present invention to provide an improved liquified gas dry-cleaning system which enables faster cleaning and quicker solvent removal upon completion of the cleaning cycle.




Another object of the invention is to provide a liquified gas dry-cleaning system as characterized above that has an agitation system adapted for enhanced cleaning and shortened cycling times.




Still another object is to provide a liquified gas dry-cleaning system of the above kind that effects thorough agitation of items during the cleaning cycle without damage to relatively fragile garments and the like.




Yet another object is to provide a liquified gas dry-cleaning system of the foregoing type that is more effective for preventing contamination of the liquified gas cleaning solvent with air. A related object is to provide such a dry-cleaning system that is operable for more effectively removing air from the system prior to introduction of the liquified gas into the cleaning chamber.




Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which:











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a schematic of a liquified gas dry-cleaning system in accordance with the invention;





FIG. 2

is an enlarged longitudinal section of the dry-cleaning pressure vessel of the system shown in

FIG. 1

;





FIG. 3

is an enlarged fragmentary section taken along


3





3


in

FIG. 2

, showing the rotational mounting of the rotary basket shaft within the pressure vessel housing;





FIG. 4

is a longitudinal section of the rotary basket;





FIG. 5

is a vertical section of the rotary basket, taken in the plane of lines


5





5


in

FIG. 4

;





FIG. 6

is an enlarged fragmentary section showing the mounting of a rotary basket mixing baffles to the outer peripheral wall of the basket;





FIG. 7

is an enlarged fragmentary section of an upstream end of the rotary basket, as encircled with the area referenced “


7


” in

FIG. 2

; and





FIG. 8

is an enlarged fragmentary section of a downstream end of the basket, as encircled by the area referenced “


8


” in FIG.


2


.




While the invention is susceptible of various modifications and alternative constructions, a certain illustrated embodiment thereof has been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions and equivalents falling within the spirit and scope of the invention.











DETAILED DESCRIPTION OF THE DRAWINGS




Referring now more particularly to

FIG. 1

of the drawings, there is shown a diagrammatic depiction of an illustrative liquified gas, dry-cleaning machine


10


embodying the present invention. In general, the dry-cleaning machine


10


includes a pressure vessel


12


having a perforated basket


14


disposed therein for containing items


15


to be cleaned. A liquid wash bath derived from a liquifiable gas, such as carbon dioxide, is used as the dry-cleaning solvent. A pump


16


is provided for directing the wash bath from a storage tank


18


and through an inlet line


19


into the pressure vessel


12


. The pressure vessel


12


is equipped with a steam heater


20


, pressure sensor


21


, and temperature sensor


22


to aid in temperature and pressure control for properly maintaining the wash bath in liquid phase during the dry-cleaning cycle.




The basic operation of a liquid gas dry-cleaning system is known in the art, as reflected by U.S. Pat. Nos. 5,651,276, 5,467,492, and 5,651,276, the disclosures of which are incorporated herein by reference. After the basket


14


is loaded with items, such as garments, for cleaning, the pump


16


charges the vessel


12


with a wash bath drawn from the storage tank


18


which functions as the cleaning solvent during a drying cycle. Upon completion of the dry cleaning cycle, the wash bath is drained from the vessel and remaining wash bath vapors evacuated and re-liquified by an appropriate condenser for return to the storage tank.




For separating contaminants from the wash bath liquid following a cleaning cycle, the wash bath is cycled through a filtration and separator system


25


which functions to filter and vaporize the wash bath, thereby concentrating the particulate matter and other contaminants. The gaseous vapor is re-liquified in a condenser


26


for return to the storage tank


18


. The pressure vessel


12


in this instance includes an internal lint filter


28


for removing gross solids and lint from the wash bath as it is drained from the pressure vessel, as disclosed in commonly assigned application Ser. No. 09/338,653, filed Jun. 23, 1999, the disclosure of which is incorporated herein by reference.




The illustrated pressure vessel


12


, as best depicted in

FIG. 2

comprises an elongated cylindrical housing having a rounded end wall


30


integrally formed at one end and a removable door


31


, also of generally rounded configuration, releasably secured at the other end. The removable door


31


has an outer annular retaining flange


32


secured in abutting relation to the end of the cylindrical housing


29


by means of a locking ring


34


threadedly engaging the end of the cylindrical housing


29


. For removing the door to permit loading and unloading of items into the cleaning vessel, an apparatus


35


may be provided for rotating the locking ring


34


to an unlocked position, and automatically removing and lowering the door


31


, as disclosed in commonly assigned application Ser. No. 09/339,590 filed Jun. 23, 1999, the disclosure of which is incorporated herein by reference.




The basket


14


for receiving and containing items to be cleaned is substantially coextensive in length with the cylindrical housing


29


and has an outer cylindrical perforated sleeve


36


, preferably made of stainless steel, which is formed with a plurality of longitudinal rows of openings


38


for enabling circulation of the liquid wash bath through the basket


14


during wash and rinse cycles. The perforated sleeve


36


is secured, such as by weldments, between a perforated back plate


39


and a conical front member


40


that defines a central inlet opening


41


to the basket


14


when the door


31


is opened. The internal lint filter


28


is disposed in a lower quadrant of the pressure vessel


12


below the conical front member


40


in communication with a drain


42


of the pressurized vessel


12


.




For supporting the basket


14


for rotating movement relative to the pressure vessel


12


, the basket


14


has an outwardly extending support and drive shaft


45


extending through the pressure vessel end wall


30


and a spider-configured trunion


46


fixed to the shaft


45


and back plate


39


. The drive shaft


45


is rotatably supported with an annular collar or bushing


48


affixed in outstanding relation to the end wall


30


of the pressure vessel by screws


47


. For supporting the opposite end of the basket


14


for rotational movement when the door


31


is in a closed position, the conical front member


40


terminates in an annular ring


49


that is received and supported within a groove


50


of an annular pilot plate


51


fixed within an annular recess of door


31


(FIG.


8


).




In order to rotate the basket


14


at selective speeds and rotary directions based upon the degree and type of agitation desired, a variable speed, bi-directional motor


55


is provided. The motor


55


drives a drive sheave


56


secured on the outwardly extended end of the basket support and drive shaft


45


via a V-belt


58


.




For enhancing agitation of items contained within the basket and the wash bath during cleaning, rinse and draining cycles, the basket


14


has a plurality of longitudinal mixing baffles


60


, oriented parallel to the rotary axis of the basket


14


, which extend radially inwardly from the outer periphery of the perforated sleeve


36


. The longitudinal baffles


60


are disposed at circumferential spaced intervals within the basket


14


and extend between the end plate


39


and the conical front member


40


. The baffles


60


preferably have an inwardly tapered or V-shaped configuration, as shown in

FIG. 6

, and are fixed to the inside surface of perforated sleeve


36


by screws


61


. In order to provide adequate mechanical agitation of both items contained within the basket and the bath wash, the baffles


60


preferably have a radial length “l” that is at least {fraction (1/10)} of the diameter of the basket.




It will be seen that upon rotation of the basket


14


through selected operation of the motor


55


, the radially projecting baffles


60


will engage, mix, and agitate the wash bath and items contained in basket. The baffles


60


similarly turn and agitate items following a wash cycle to facilitate removal of liquified gas cleaning solvent. In that latter case, enhanced agitation of the items following a cleaning operation not only is effective for enhancing removal of the liquid solvent from the cleaned items, and hence shortening the draining/drying cycle, the mechanical and frictional agitation of the items during such process tends to raise the temperature of the items and offset a temperature drop that may occur by reason of evacuation of wash bath vapors from the pressure vessel during and at the end of the wash cycle, prior to removal of the items from the pressure vessel.




In accordance with an important aspect of the invention, to augment mechanical baffle agitation, a gas jet agitating system is provided which is operable for directing pressurized liquified gas jets or streams against evolving surfaces of items contained within the basket during a wash cycle as they are moved and turned as an incident to rotary basket movement. The illustrated gas jet agitation system includes a plurality of peripheral gas jet delivery manifolds


65


that each extend along the length of a respective mixing baffle


60


. The illustrated manifolds


65


are in the form of tubes formed with a plurality of longitudinally spaced discharge orifices


66


for directing a plurality of pressurized liquified gas streams or jets into the basket


14


simultaneously with rotational movement of the basket. It will be understood that in an alternative to simplify the orifices


66


formed in the manifold tubes


65


, individual spray nozzles could be mounted in the manifold tubes designed for imparting a desired spray characteristic.




In carrying out the invention, the manifold tubes


65


are protectively seated on radial ends of the baffles


60


in a manner that eliminates possible edges or crevices that might snag or damage items within the basket during cleaning. The radial ends of the baffles


60


in this instance each are formed with a respective U-shaped longitudinal channel or recess


68


of a diameter substantially similar to the diameter of the manifold tube


65


, as depicted in FIG.


6


. The manifold tubes


65


are disposed within the U-shaped channels


68


such that at least half of the tube


65


is effectively contained within the baffle channel


68


, with the remaining circumferential portion of the tube defining the inner radial end of the baffle


65


. The discharge openings


66


in the manifold tubes


65


preferably are oriented such that pressurized flow streams of liquified gas are directed radially into the basket during cleaning.




It will be appreciated by one skilled in the art that since the manifold tubes


65


are not completely contained within the baffle


60


, there is no need for forming the baffle


60


with apertures or slots, which would require alignment with the manifold orifices


66


during assembly. Instead, the manifold tubes


65


are simply assembled into the U-shaped panel channels and secured in place. For securing the ends of the manifold tubes


65


adjacent the removable door


31


, a respective plug


69


is positioned into the end of each manifold tube


65


and secured to the conical front member


40


of the basket


14


by screws


70


. For enabling the supply of pressurized liquid gas to the manifold tubes


65


, the opposite, upstream ends of each manifold tube


65


is supported in sealed fluid communication with a respective hollow leg


72


of the spider-shaped trunion


46


, which in turn communicate with a fluid passage


74


in the drive and support shaft


45


. An O-ring


73


in this case provides the seal about the upstream end of each manifold tube


65


(FIG.


7


). Not only are the manifold tubes


65


easily assembled on the baffles


60


by inserting the upstream ends into the spider legs


72


and securing the respective plug


70


to the front basket member


40


, they are easily removable for periodic cleaning and/or replacement.




In order to supply pressurized liquified gas to the manifold tubes


65


, the bushing


48


affixed to the end of the pressure vessel


12


defines an annular flow chamber


75


about a portion of the shaft


45


immediately adjacent the external side of the pressure vessel. The inlet line


19


from the liquid supply pump


16


is connected to and communicates with the annular chamber


75


via a threaded aperture


76


in the side of the bushing


48


, as depicted in FIG.


3


. The annular chamber


75


is sealed by lip seals


78


,


79


interposed between the bushing


48


and shaft


45


at opposite axial ends of the annular chamber


75


, and a radial washer


80


, retainer ring


81


, thrust bearing


82


, and radial bearing


83


are disposed outboard of the lip seal


79


to accommodate axial and radial forces exerted by the drive shaft


45


by virtue of the high pressure within the vessel


12


. The annular bearing and seal chamber


75


communicates through a plurality of radial apertures


84


in the drive shaft


45


with the shaft passage


74


, which in this case is defined between end plugs


88


,


89


secured in opposite ends of the tubular drive shaft


45


. The drive shaft passage


74


in turn communicates through a plurality of radial apertures


90


in the drive shaft


45


with respective hollow legs


72


of the spider-shaped trunion


46


, which in turn, as indicated above, each communicate with a respective manifold tube


65


. It can be seen that liquified gas directed through the supply line


19


into the annular chamber


75


, will enter the drive shaft passage


74


, and be directed through the trunion legs


72


to the respective manifold tubes


65


for discharge in the form of a plurality of longitudinally spaced, radially directed, pressurized liquid gas flow streams.




Preparatory to a wash cycle, the pressure vessel


12


may be charged with a wash bath from the same liquified gas supply tank


18


and inlet manifolds


65


as used during gas agitation. During a wash cycle, the basket


14


preferably is driven in alternative rotary directions by the drive motor


55


to prevent tangling of items within the basket


14


and to facilitate evolving and turning movement of the items such that surfaces thereof continually are exposed and impinged by the liquified gas jets emitted from the circumferentially spaced gas jet agitation manifolds


65


. While the liquified gas jet streams are radially emitted from the manifolds


65


, it will be appreciated that rotary movement of the basket


14


imparts a tangential element of movement to the gas streams such that they in effect impinge the items at angles, which minimizes possible damage to fragile garments and the like within the wash basket. In practice, it has been found that effective agitation and cleaning is achieved when the basket


14


is rotated such that the baffles


60


, and hence the manifolds


65


mounted thereon, are moving at a tangential speed of about 10 feet per second and the manifold apertures


66


are sized such that at a liquid discharge pressure, such as about 120 psi above the cleaning chamber pressure, the liquified gas jets are emitted from the manifolds


65


at about 100 feet per second. During such operation, surfaces of the continually moving and evolving items within the wash basket are repeatedly exposed to the liquified gas jet agitation. The combined agitation of both the wash bath and items contained therein from the baffles and liquid gas jets effectively increases contact of the wash bath with the garments for enhanced washing effectiveness. The contribution of the jets further is effective for physically dislodging and removing even very small sized insoluble soils, such as 2 to 3 microns in diameter and less.




As understood by those skilled in the art, cleaning effectiveness and efficiencies can be adversely affected by other factors, including the presence of air in the pressure vessel


12


and the liquified gas cleaning solvent. Air can be introduced into the system by entrapment within the fabric mesh of items deposited into the pressure vessel for cleaning. The presence of air in the liquified gas cleaning solvent can negatively impact the dry cleaning process by both diluting the cleaning fluid by creating pump cavitation, and air locking the underlocking system, the condensing system.




In accordance with a further aspect of the invention, the dry cleaning machine has a gas purging cycle of operation which facilitates more complete removal of entrapped air from items placed within the pressure vessel prior to charging the pressure vessel with the liquid carbon dioxide cleaning solvent. To this end, the purging cycle includes (a) introducing a pressurized gaseous carbon dioxide into the pressure vessel


12


while the pressure vessel is sealed; (b) rotating the basket to flex items contained therein so that the entrapped air is allowed to escape into the introduced gaseous CO


2


; and (3) venting the gaseous CO


2


and released air from the pressure vessel. Preferably, the purging cycle is successively repeated up to 3 times, prior to introducing the liquid carbon dioxide wash bath into the pressure vessel for removing all but small traces of air from the contained items prior to cleaning.




In the illustrated embodiment, following loading of the pressure vessel with items to be cleaned and closing the door


31


to seal the washing chamber, gaseous carbon dioxide is directed from a purge tank


95


through a vent valves


96


,


98


through the top of the pressure vessel


12


(FIG.


1


). The gaseous carbon dioxide preferably is directed into the pressure vessel


12


at a pressure of about 30 psi (2 atmospheres) for approximately 3 seconds, the basket


14


is thereafter rotated for 3 seconds to turn, flex and mix the items within the basket sufficient to release at least a portion of air that is entrapped within the fabric mesh of the items, and thereafter, the introduced carbon dioxide gas and released air is vented to atmosphere for a similar short period of 3 seconds. Such purging cycle preferably is repeated two additional times to successively release and vent substantially all of the air entrapped within the items to be cleaned.




In practice, carrying out the purging cycle three successive times over a period of less than 30 seconds, has been found effective to remove more than 95% of the entrapped air. While the theory of operation of the purge cycle is not entirely understood, the following is believed to be the basis for its effectiveness. The purge process begins with the introduction of gaseous CO


2


at 2 atmosphere pressure into the closed cleaning chamber defined by the pressure vessel. After tumbling the garments, the mixture of 1 part air, 2 parts CO


2


is vented. The process is repeated with the reintroduction of 2 atmospheres of pure CO


2


. The resulting venting mixture is 1 part air, 8 parts CO


2


. A third repetition will generate a mixture within the cleaning vessel of 1 part air, 26 parts CO


2


. the resulting amount of air relative to the total mixture is (⅓)


n


where


n


is the number of purges. Hence, following the purge cycle, introduction of the liquified gas enables the cleaning cycle to efficiently carried out without appreciable air contamination.




From the foregoing, it can be seen that the liquified gas dry cleaning system of the present invention is adapted for faster and more efficient cleaning. The system includes a combined mechanical and gas jet agitation system which in combination enhances cleaning and shortens cycling times. The dry cleaning system, furthermore, is effective for preventing contamination of the liquified gas with air from items introduced into the pressure vessel for cleaning.



Claims
  • 1. A liquified gas dry-cleaning system comprising:a pressure vessel for containing a wash bath of a liquified gas under pressure. a basket rotatably supported within the pressure vessel for containing items during cleaning; a drive for rotating the basket within the vessel; said basket having a plurality of baffles mounted on a periphery thereof and extending radially inwardly into said basket for physically contacting and agitating the wash bath and items contained within the basket during a dry-cleaning cycle as an incident to rotation of the basket; a gas jet agitation system having a plurality of nozzles mounted on said basket; and a liquified gas supply operable for selectively directing liquified gas to said nozzles which in turn direct pressurized jet streams of liquified gas into the basket for further agitating the items contained within the basket and the liquid wash bath simultaneously with agitation by said baffles as an incident to basket rotation.
  • 2. The liquified gas dry-cleaning system of claim 1 in which said baffles extend parallel to the rotary axis of said basket.
  • 3. The liquified gas dry-cleaning system of claim 2 in which said baffles extend radially into the basket a distance of at least one-tenth the diameter of the basket.
  • 4. The liquified gas dry-cleaning system of claim 1 in which said spray nozzles are defined by a plurality of manifold tubes disposed about the periphery of said basket.
  • 5. The liquified gas dry-cleaning system of claim 4 in which said manifold tubes and baffles and manifold tubes extend parallel to the rotary axis of said basket.
  • 6. The liquified gas dry-cleaning system of claim 4 in which said nozzles are defined by a plurality of axially spaced discharge apertures in said manifold tubes.
  • 7. The liquified gas dry-cleaning system of claim 6 in which said apertures are configured for directing pressurized jet streams of liquified gas radially into said basket.
  • 8. The liquified gas dry-cleaning system of claim 4 in which an inner radial end of each said baffle is formed with a recess, and said manifold tubes each are mounted within a respective baffle recess.
  • 9. The liquified gas dry-cleaning system of claim 8 in which said baffle recesses are substantially U-shaped, and said manifold tubes each are mounted in a baffle recess with at least half of the circumferential periphery of the tube protectively contained within the recess.
  • 10. The liquified gas dry-cleaning system of claim 9 in which said manifold tubes define inner radial ends of said baffles.
  • 11. The liquified gas dry-cleaning system of claim 4 in which said baffles each have a substantially V-shaped cross section, and said manifold tubes are mounted at the apex of each said substantially V-shaped baffle.
  • 12. The liquified gas dry-cleaning system of claim 4 in which said basket has a shaft supported for relative movement within said pressure vessel, a trunion supported by said shaft having a plurality of radially extending hollow legs each being in fluid communication with one of said manifold tubes, and said liquid supply is operable for directing pressurized liquified gas to said trunion for communicating liquified gas through said trunion legs to said manifold tubes.
  • 13. The liquified gas dry-cleaning system of claim 12 in which said basket shaft is supported by an annular bushing mounted outwardly of said pressure vessel, said bushing defining an annular chamber about said shaft, said liquid supply being operable for directing liquified gas to said annular chamber, and said shaft being formed with an internal passage communicating with said annular chamber and said trunion legs for enabling communication of liquified gas from said annular chamber through said shaft passage, trunion legs, and manifold tubes.
  • 14. The liquified gas dry-cleaning system of claim 12 in which one end of each said manifold tube is removably inserted into a respective one of said trunion legs, and the other end of each manifold tube has a removable plug mounted in the end therof and secured to a front portion of said basket.
  • 15. The liquified gas dry-cleaning system of claim 4 in which said manifold tubes are removably mounted on said baffles.
  • 16. The liquified gas dry-cleaning system of claim 1 in which said basket includes an outer cylindrical perforated sleeve, and said baffles are mounted in inwardly extending relation to said perforated sleeve.
  • 17. The liquified gas dry-cleaning system of claim 1 in which said pressure vessel includes a door mounted for movement between open and closed positions, said basket having a support shaft extending outwardly through said pressure vessel from one end of said basket, and the other end of said basket defining an entry opening through which items may be loaded into the basket when said door is in an open position.
  • 18. The liquified gas dry-cleaning system of claim 17 in which said other end of said basket defines an annular ring, and said door being formed with an annular recess for receiving and supporting said basket for relative rotational movement when said door is in a closed position.
  • 19. The liquified gas dry-cleaning system of claim 18 in which said other basket end has a conical form which terminates in said ring and which defines said front entry opening.
  • 20. A liquified gas dry-cleaning system comprising:a pressure vessel for containing a wash bath of a liquified gas under pressure; a basket rotatably supported within the pressure vessel for containing items during cleaning; a drive for rotating the basket within the vessel; a gas jet agitation system having a plurality of nozzle mounted on said basket; a liquified gas supply operable for selectively directing liquified gas to said nozzles which in turn direct pressurized jet streams of liquified gas into the basket for agitating the items contained within the basket and the liquid wash bath; said pressure vessel including door mounted for movement between open and closed positions; said basket having a support shaft extending outwardly through said pressure vessel from one end of said basket, the other end of said basket having an annular ring defining an entry opening through which items may be loaded into he basket when said door is in an open position; and said door being formed with an annular recess for receiving and supporting said annular ring of the basket for relative rotational movement when said door is in a closed position.
  • 21. The liquified gas dry-cleaning system of claim 20 in which said basket has a conical end which terminates in said ring.
  • 22. A liquified gas dry-cleaning system comprising:a pressure vessel for containing a wash bath of a liquified gas under pressure; a basket rotatably disposed within the pressure vessel for containing items during cleaning; said basket having a shaft supported for rotation relative to said pressure vessel; a drive for rotating said shaft and basket; a gas jet agitation system having a plurality of manifold tubes mounted on said basket; said manifold tubes having a plurality of spaced apart discharge orifices; a trunion supported by said shaft having a plurality of radially extending hollow legs each being in fluid communication with one of said manifold tubes; and a liquified gas supply operable for selectively directing liquified gas to said trunion for communicating liquified gas through said trunion legs to said manifold tubes which in turn direct pressurized jet streams of liquified gas through said discharge orifices into the basket for agitating the items contained within the basket and the liquid wash bath during a dry-cleaning operation.
  • 23. The liquified gas dry-cleaning system of claim 22 in which said basket shaft is supported by an annular bushing mounted outwardly of said pressure vessel, said bushing defining an annular chamber about said shaft, said liquid supply being operable for directing liquified gas to said annular chamber, and said shaft being formed with an internal passage communicating with said annular chamber and said trunion legs for enabling communication of liquified gas from said annular chamber through said shaft passage, trunion legs, and manifold tubes.
  • 24. The liquified gas dry-cleaning system of claim 22 in which one end of each said manifold tube is removably inserted into a respective one of said trunion legs, and the other end of each manifold tube has a removable plug mounted in an end thereof and secured to a front end portion of said basket.
  • 25. A liquified gas dry-cleaning method using a pressure vessel having an internal basket for containing items to be cleaned comprising the steps of introducing items to be cleaned into said basket, sealing said pressure vessel, introducing into said vessel under pressure a liquified gas wash bath, rotating said basket to agitate the wash bath and items contained therein during a cleaning cycle, and directing a plurality of pressurized jet streams of liquified gas into said basket from a plurality of discharge orifices located within said basket for causing higher velocity movement of the liquid wash bath and items contained therein simultaneously with agitation as an incident to basket rotation during a cleaning cycle.
  • 26. The method of claim 25 including repeatedly reversing the direction of rotary movement of said basket during the cleaning cycle.
  • 27. The liquified gas dry-cleaning method of claim 25 including directing pressurized jets of liquified gas into said basket by directing liquified gas through a plurality of manifold tubes mounted on said basket for rotation therewith.
  • 28. The liquified gas dry cleaning system of claim 25 in which during each air purge cycle the gaseous form of the liquified gas is introduced into said pressure vessel at a pressure of about 30 psi.
  • 29. A liquified carbon dioxide gas dry-cleaning method using a pressure vessel having a internal basket for containing items to be cleaned comprising the steps of:introducing items to be cleaned into said basket; sealing the pressure vessel; carrying out an air purge cycle by introducing under pressure a gaseous form of carbon dioxide into said pressure vessel, rotating said basket so that items within the basket are turned and flexed to release at least a portion of any contained air therein, venting the introduced carbon dioxide gas and released air from the pressure vessel; repeating the air purge cycle at least one additional time; re-sealing the pressure vessel following the final gas purge cycle; and carrying out a dry-cleaning cycle by introducing under pressure a wash bath of liquified carbon dioxide gas into the pressure vessel, and rotating the basket to agitate the contained items and wash bath during the dry cleaning cycle.
  • 30. The liquified carbon dioxide dry cleaning method of claim 29 including repeating said air purge cycle three times prior to carrying out the dry-cleaning cycle.
  • 31. The liquified carbon dioxide gas dry-cleaning method of claim 29 in which during each air purge cycle gaseous carbon dioxide is introduced into said pressure vessel for about three seconds, the basket is rotated for about three seconds, and the gaseous carbon dioxide and released air is vented for about three seconds.
  • 32. The liquified carbon-dioxide gas dry-cleaning method of claim 29 in which during each air purge cycle the gaseous carbon dioxide is introduced into said pressure vessel at a pressure of about 30 psi.
  • 33. The liquified carbon dioxide gas dry cleaning method of claim 29 including the step of introducing pressurized streams of liquified carbon dioxide gas into said basket simultaneously as the basket is rotated during a dry cleaning cycle to augment agitation and cleaning of items contained therein.
  • 34. A liquified gas dry-cleaning method using a pressure vessel having an internal basket for containing items to be cleaned comprising the steps of introducing items to be cleaned into said basket, sealing said pressure vessel, introducing into said vessel under pressure a liquified gas wash bath, rotating said basket to agitate the wash bath and items contained therein during a cleaning cycle, directing a plurality of pressurized jet streams of liquified gas into said basket for causing higher velocity movement of the liquid wash bath and items contained therein simultaneously with agitation as an incident to basket rotation during a cleaning cycle, carrying out an air purge cycle prior to introducing the liquified gas wash bath into the pressure vessel, said air purge cycle including the steps of introducing into said vessel under pressure of a gaseous form of the liquified gas which makes up the wash bath, rotating the basket so that the items within the basket are turned and flexed to release at least a portion of any contained air therein, venting the introduced gas and released air from the pressure vessel, and repeating the gas purge cycle at least one additional time.
RELATED APPLICATION

This application is a continuation-in-part of U.S. application Ser. No. 08/998,399, filed Dec. 24, 1997 now U.S. Pat. No. 6,012,307.

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Continuation in Parts (1)
Number Date Country
Parent 08/998399 Dec 1997 US
Child 09/338292 US