Abstract:
A portable parts washing machine using a washing solvent to wash motor parts or the like. The apparatus has a stowed configuration and an operating configuration. In the operating configuration, a solvent container/wash basin is positioned on a base section which also functions as a solvent reservoir. Solvent is recirculated by a pup and recirculating line fro the reservoir to the wash basin, with the solvent washing the parts and then flowing through a drain in the wash basin into a centrifugal filter. The centrifugal filter removes the contaminates, with the solvent returning to the reservoir. In the stowed configuration, the base section, centrifugal filter and solvent recirculating assembly are stowed in the container.

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 09/105,777, filed Jun. 26, 1998, now U.S. Pat. No. 6,068,707 which in turn claims the priority of U.S. Provisional Application 60/050,827 filed Jun. 26, 1997. This application is a continuation of U.S. patent application Ser. No. 08/783,692, filed Jan. 15, 1997 (now U.S. Pat. No. 5,954,071). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to the field of portable parts washing apparatus, and particularly to a portable parts washing apparatus having a centrifugal filter to separate foreign waste elements from a cleaning solvent. 
     2. Background Art 
     Parts washers are widely used in industrial applications, and in particular, automotive service shops. The most familiar part washer can be found in almost any service station in the country. It is comprised of a sink with a spigot and a drain that sits upon a standard 55 gallon drum. The drum is partially filled with a parts washing solvent. The solvent is pumped from the drum, through the spigot, where it flows over the dirty part, into the sink&#39;s drain, from which it falls back into the drum. In this manner, the solvent continuously flows over the dirty part while the operator washes the part in the sink. 
     There has long been an unmet need for a portable parts washer that can be easily moved to a field location. An example of such an unmet need is military deployment. Military equipment in use in the field requires maintenance that cannot be done in a regular service shop either because of logistics or simply convenience. A portable parts washer would also be useful for applications outside of the military. For example, repairing and maintaining heavy machinery on site of a construction project or at a logging camp. It has been impractical to move parts washers to the field because of their size, weight, and configuration. As a substitute for this very useful device, a parts washer in the field consists of a bucket filled with solvent in which a part is dipped and washed by hand. The bucket is emptied when the solvent becomes saturated with dirt. This practice is inefficient, wasteful, and environmentally hazardous. 
     Despite the multitude of advantages over the bucket method that the basic configuration of the parts washer (sink, barrel and solvent moving means) has, it is believed that few, if any, conventional parts washers are used during a military deployment. This is largely because conventional parts washers are impractical to move and take up much more cargo space than justifies their use. The sink portion of the conventional parts washers are made of steel for fire safety reason and are therefore very heavy. In addition, a typical 55 gallon drum half-filled with solvent could easily weigh several hundred pounds. Since the pump of these conventional parts washers is most often suspended from below the sink, damage during transport is very likely. Exposed this way, it is almost certain that the bracket, the pump, the hoses, or any combination of the three would be damaged. The parts washer would also take up a great deal of space, space that is at a premium on a military deployment. 
     Of the many patents discussed below that are concerned directly with parts washers, only U.S. Pat. No. 4,462,415 (Otzen) even teaches a solvent tank designed to be taken to a reclamation facility to be exchanged for fresh solvent. This patent describes a low cost parts washer intended for use by the occasional user and adapted for self-service fluid changes. The unit has a modular solvent tank of modest capacity that can be removed from the parts washer, capped in several places, and returned to a distributor for exchange with a solvent tank containing fresh solvent. There is no filtering means inside the solvent tank. 
     In addition to being impractical to move, the problem with conventional parts washers is that the foreign material washed from the dirty part flows into the drum along with the solvent. In many applications, the foreign material will be comprised of metal shavings, dirt, sand, grit, and oil particulates. Since much of this debris will remain suspended in the solvent while the pump is running, the pump is continuously subjected to substances that will damage its internal seals. Much of the background art in this area has addressed this particular problem by placing a filter upstream of the pump to strain the foreign debris from the solvent before it reaches the pump. For instance, in U.S. Pat. No. 4,056,114 (Boutillete), the pump is surrounded by a filter element. U.S. Pat. No. 3,890,988 (Lee) teaches a pump mounted at the top of a truncated cone that rests at the bottom of a solvent tank. The cone is made from a screen that is intended to filter the solvent before it reaches the inlet of the pump. U.S. Pat. No. 5,464,533 (Koslow) teaches a two stage active filter that is located inside an extended pump housing. Instead of having the filter continuously in line with the pump, U.S. Pat. No. 5,368,653 (Russell) teaches a filter that can be periodically used at the discretion of the user. 
     Trapping the gunk and the solvent together until the solvent drains from the filter, however, insures that the gunk will retain a substantial amount of the solvent. This wet waste material will eventually condense into a thick, gummy, oily substance, commonly referred to in the art as “gunk.” 
     In U.S. Pat. No. 3,378,019 (Riolo et al.) the patent teaches a paper filter located below the drain. The solvent flows through the filter with only the assistance of gravity. Similarly, in U.S. Pat. No. 3,960,728 (Otzen) a filter bag is described that hangs from the drain. U.S. Pat. No. 5,522,814 (Olson) teaches a gravity filter comprising a compartment filled with waste cotton located below the drain. U.S. Pat. No. 2,675,012 (Scales) notes that these types of gravity filters are quickly obstructed by the gunk and will not filter the solvent. Accordingly, Scales teaches a complex set of superposed sludge settling trays of successively decreasing diameters. In U.S. Pat. No. 4,226,548 (Reith) the sludge trap is located under a screen that covers the interior bottom of the sink. The solvent flows over a ridge to a drain while the sediment settles on the other side of the ridge. 
     Other techniques proposed include skimming the waste materials that float on top of an aqueous cleaning solution as is taught in U.S. Pat. No. 5,303,725 (Hilgren), or simply distributing the solvent as it drains so it does not upset the sediment that has collected at the bottom of the drum as is described in U.S. Pat. No. 4,505,284 (Kyatt). U.S. Pat. No. 2,085,075 (Delano) teaches a portable crankcase flusher and cleaner that introduces, extracts, and filters cleaning fluid from the crankcase of an automobile using a complicated reversible one-way valve. Solvent is introduced to the crankcase, removed and cycled trough a centrifuge, and returned to the crankcase several times. The second major effect of the foreign matter flowing freely into the drum along with the solvent is that, as the foreign material settles to the bottom of the drum it will accumulate and condense into gunk. This gunk layer will eventually foul, and probably damage, the pump. In any case, the solvent in the drum will eventually be so full of gunk and suspended matter that it will have to be replaced and the old solvent disposed of. In the age before hazardous waste laws, this problem was addressed in the art by using plastic drum liners that would capture the solvent, the foreign materials, and the gunk so that they could all be disposed of together—probably ending up in a landfill (assuming the liner made it that far without being punctured). This disposable liner concept is taught in U.S. Pat. Nos. 3,890,988 (Lee). 3,552,814 (Olson); 4,056,114 (Boutilette). 
     Contrary to a suggestion in the Lee patent, it is no longer possible to remove the gunk and solvent together in a plastic liner to be disposed of in a landfill or, for the matter, in the dirt behind the service station. The solvents used in parts washers are now classified as hazardous waste materials and are heavily regulated by both state and federal law. There are severe civil and criminal penalties for the improper disposal of the waste materials associated with these parts washers. Similarly, it is no longer practical to clean the gunk from the parts washers because the gunk still has to be disposed of as hazardous waste. 
     Because of the hazardous waste laws, a huge industry has developed to service parts washers. The 1995 annual report from the largest of these service providers reports reclaiming more than 210 million gallons of contaminated fluids and discloses revenues in this area are in excess of $240 in dollars per year. Servicing the parts washers usually means removing the sink from the drum, capping the used drum off, and transporting the used solvent and gunk contained in the drum to a reprocessing plant. Evidencing the major concern that the industry has over hazardous waste liability, this service provider also advertises that it indemnifies the customer against liability hazardous waste spills that may occur while the solvent is being transported. 
     In the portable applications such as is described in the present application, the significance of the environmental concerns often comes second to the need for the solvent to remain mostly waste free for relatively long periods of time under heavy use. In the example of a military deployment, the fewer parts washers that need to be deployed, the less the supply lines are burdened. It is axiomatic that the fewer parts washers available in the field, the harder they will be used. 
     Perhaps most importantly, many of the designs discussed above rely on the solvent tank remaining stationary so that the waste materials settle to the bottom of the tank where they are out of the way. The motion inherent in moving the solvent tank from one location to another would freely mix the waste materials back into the solvent, making many of the methods involved in the previous patents ineffective, and the moving of the conventional parts washer to another location almost useless. 
     SUMMARY OF THE INVENTION 
     The primary components of the present invention are a container, a base assembly, a solvent recirculating means, and a centrifugal filter assembly. When in use as a parts washer, the lower portion of the container is used as a sink and the upper portion of the container is used as a fire suppression lid. The container assembly rests upon the base assembly which houses the solvent, solvent recirculating means and the centrifugal filter assembly. The solvent recirculating means is connected to a nozzle and hose assembly inside the sink by a quick-disconnect hose specially configured for that purpose. 
     To configure the present invention for transport, the quick disconnect hose is removed from its connections to the sink and the base assembly. The container assembly is then lifted from the base assembly. The base assembly is capped and then placed into the container assembly. The quick-disconnect hose is placed alongside the base assembly, as is the nozzle and hose assembly inside the sink. The cover portion of the container assembly is then lowered and temporarily secured to the sink portion. The portable parts washer is then carried to the next location by the handles placed on the outside of the container assembly for that purpose. Setting up the portable parts washer is this same process in reverse—open the container assembly, remove the base assembly and uncap it, place the container housing on top of the base assembly, and connect the quick-disconnect hose. 
     In the preferred embodiment of the invention, a centrifugal filter assembly is incorporated into the base assembly. This is because of the problem of keeping the solvent clean that is described by many of the patents discussed above. These patents all describe their methods of addressing the same problem—separating and removing the gunk from the solvent. The portable parts washing apparatus of the present invention significantly reduces this problem in a manner significantly more effective than what has been available, and the hazardous waste problems associated with parts washers, by materially reducing the formation of the gunk by reducing the foreign waste material that reaches the solvent tank. This is done by employing a centrifugal filter assembly between the drain of the container assembly parts washing basin and the solvent storage tank. In this position, the centrifugal filter removes most of the foreign particulate matter from the solvent before the solvent is returned to its storage container. More importantly, however, is that the centrifugal filter removes the foreign waste material from the solvent before it can condense into the paste-like gunk at the bottom of the solvent storage tank. Instead, the centrifugal action of the filter squeezes the solvent from the foreign waste materials while the foreign waste material is still a small part of the solvent stream. A purified solvent is returned to the container, while the mostly-dried foreign matter is retained in the filter. In the preferred form, a secondary “screen” filter is used at the drain of the basin to capture larger foreign objects, including components that may fall off the part being washed. These filtering means enable the solvent to be recirculated almost indefinitely while remaining mostly free of gunk formation. 
     It is important to note that most of the foreign material is captured by the primary centrifugal filter, leaving a relatively clean solvent for reuse. In particular, the centrifugal filters solves the problems associated with gunk accumulating at the bottom of a tank. The centrifugal action of the primary centrifugal filter spins most of the solvent out of the foreign material, leaving behind a body of foreign materials captured in the filter that is almost dry. Instead of capping off the whole solvent drum and sending it for reprocessing, the only material that need be sent to a hazardous waste facility are the disposable filters and their contents, which can easily be placed in a canister the size of a coffee can. This means that shipping and waste disposal fees will be significantly less, the danger of a hazardous waste spill will be considerably reduced, and the cost of replacing the solvent will almost be eliminated for most applications. 
     In portable applications, the centrifugal filter keeps most of the contaminants out of the solvent, so the problem of settled contaminates remixing with the solvent during transport is also considerably lessened. 
     To present further aspects of the present invention, the apparatus of the present invention can be considered as comprising a containing section and a base section. The containing section comprises a containing member defining a containing chamber. The containing chamber functions in a first configuration (the stowed configuration) as a stowing container, and functions in the second configuration (the operating configuration) as a wash basin having a parts and solvent containing region. The containing member has a drain configured to retain parts in the container to permit solvent to pass through the drain. 
     The base section is configured to be positioned in the containing chamber of the containing member in the first stowed configuration, and also configured and arranged to function in the second operating position as a base support for the containing member and also a solvent reservoir. The base section defines a solvent containing region positioned below the containing section in the second configuration. The centrifugal filter in the first configuration is stowed in the containing member and in the second configuration it is positioned to receive the solvent from the drain. The centrifugal filter comprises a rotatably mounted filter receptacle with filter means to retain impurities from the solvent in the receptacle and permit the solvent to flow through the filter means and into the solvent reservoir. 
     There is a recirculating assembly which comprises a pump and recirculating line means. It is arranged so that in the operating configuration the pump moves the solvent from the solvent containing region through the recirculating line means to the wash basin of the containing member and in the first stowed configuration is in the containing member. 
     In the preferred form, the containing section further comprises a cover member which in the stowed configuration functions as a cover for the containing member. In the operating configuration, the cover member is movable from an open position to a closed position to be able to function as a flame suppresser. 
     The containing member and the base member have interfitting positioning means by which the containing member can be properly positioned on the base section in the operating configuration. More specifically, the base section has an upper end opening, and the containing member has at its lower end a downwardly extending interfitting member which interfits with an upper end portion of the base section. Desirably, the interfitting member comprises a circumferential collar fitting within the base section, and in the operating configuration the centrifugal filter is located in the area surrounded by the collar, so that solvent discharged from the centrifugal filter can be contained by the collar. 
     The interfitting member extends downwardly from the containing member, and the containing member has support means extending downwardly from the containing member to properly support the containing member above a ground location. 
     The centrifugal filter is mounted in the reservoir so that with the apparatus in its second operating configuration, the centrifugal filter is positioned in the base section beneath the drain of the containing member to receive the solvent from the drain. The centrifugal is arranged to be able to remain in its position in the base section when the base section is removed from the containing member and stowed in the containing member. 
     In one configuration, the pump comprises a pump motor, and the pump motor has an operative drive connection to the centrifugal filter to cause the centrifugal filter to rotate. In one form, the centrifugal filter is mounted to a mounting structure, and the motor has shaft means extending to the mounting structure. There is a drive connection extending between the shaft and the centrifugal filter to cause rotation of the centrifugal filter. In the specific form, the drive connection comprises belt and pulley drive means operatively interconnecting the shaft and the motor of the centrifugal filter. 
     In another arrangement, the centrifugal filter is provided with a fluid driven drive means to cause rotation of the centrifugal filter. The pump is arranged with a fluid supply line to deliver solvent to the fluid drive means to cause rotation of the centrifugal filter. In the specific form shown herein, the fluid drive means comprises a turbine means which is driven by solvent that is driven from the pump. 
     In the method of the present invention, the components are provided as indicated above. Initially, in the stowed position the base section is positioned in the containing member, along with the centrifugal filter and the recirculating assembly. To place the apparatus in the second configuration, the base section is removed from the container and positioned in its operating position. The containing member is placed on the base section, and the centrifugal filter and the recirculating assembly are positioned in their operating position. Then power is supplied to the pump and/or drive components to cause the solvent to be recirculated, and also to cause the centrifugal filter to rotate. Thus, the solvent is delivered from the wash basin to the centrifugal filter where the contaminating matter is removed, and the purified solvent being collected in the reservoir. Then the recirculating assembly recirculates the solvent back up to the wash basin. Other features of the present invention will become apparent from the following detailed description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front perspective view of the preferred embodiment of the portable parts washing apparatus as it appears when set up for use a parts washer. 
     FIG. 2 is a cross-sectional view of the preferred embodiment of the portable parts washing apparatus taken along line  2 — 2  found in FIG.  1 . 
     FIG. 3 is a side elevational view of the portable parts washing apparatus as configured for transport and showing the approximate position of the solvent reservoir in a circular dashed line. 
     FIG. 4 is partially exploded view of the portable parts washing apparatus indicating the two primary components of the portable parts washing system. 
     FIG. 5 is a front plan view of the portable parts washing apparatus with the solvent reservoir assembly capped and placed in the container assembly in preparation for transport. 
     FIG. 6 is a schematic drawing of the mounting bracket. 
     FIG. 7 is a schematic drawing of the one-quarter turn fasteners used to secure the cover to the washing basin. 
     FIG. 8 is a schematic drawing of the filter bag draped in the filter basket. 
     FIG. 9 is a view sectional view of a second embodiment showing a modified design of the base assembly. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The primary design features of the portable parts washing apparatus  10  that distinguishes it from the parts washers currently on the market is its design for portability and its use of a novel centrifugal filter assembly  12  first described in the parent of this application. The portable parts washing apparatus  10  has a first or parts washing operating position shown in FIG.  1 . 
     In this position, the portable parts washing apparatus  10  has a parts washing basin  14  with an attached cover  16  that rests on a base assembly  18  containing a solvent transport means  20 , the centrifugal filter assembly  12 , and a solvent reservoir  22 . In this configuration, the portable parts washing apparatus  10  resembles a conventional parts washer and is used in much the same way. 
     In the second or transport operating position, which is shown from the side in FIG. 3, the parts washing basin  14  and the cover  16  form a container assembly  24  into which the base assembly  18  is placed for transport. Once the base assembly  18  is in position inside the washing basin  14 , the cover  16  is lowered and secured with a plurality of fasteners  26 , as shown in FIGS. 3 and 7. The portable parts washing apparatus  10  may now be moved as a single unit to any location desired. In the transport operating position (FIG.  3 ), the portable parts washing apparatus  10  has all is primary operational parts safely secured within the steel container assembly  24 . There is little chance of damage to the portable parts washing apparatus  10  and the solvent  28  is protected against spillage by both the base assembly  18  and the container assembly  24 . 
     The second major design feature of the portable parts washing assembly is the use of a centrifugal filter assembly  12  to filter the solvent  28  during use. This has the benefit of enabling a long useful life for the solvent  28  and, very importantly for this application, removes most of the foreign matter washed from the parts from the solvent thus inhibiting the build up of sludge in the bottom of the solvent reservoir  22 . Since most of this waste is removed from the solvent  28  before the transport of the portable parts washing apparatus  10 , the contaminants will not be remixed into the solvent  28  every time the portable parts washing apparatus  10  is moved. This means that the portable parts washing apparatus  10  is available for use as soon as a filter  30  is reinserted into the centrifugal filter assembly  12  without having to replace the solvent  28  every time the unit  10  is moved. 
     The preferred embodiment of the portable parts washing apparatus  10  of the present invention will now be described. In FIG. 1, the portable parts washing apparatus  10  is shown in the parts washing operating position. There is a container assembly  24  that is comprised of a parts washing basin  14 , a cover  16  attached to a rear edge of the parts washing basin  14  by a piano hinge  32 , a support  34  to keep the cover  16  up during the operation of the portable parts washing apparatus  10 , a solvent directional means  36  to direct the flowing solvent  28  over the dirty part, a left support leg  38 , a right support leg  40 , and a collar  42  attached concentrically with an aperture  44  formed in a base wall  46  of the washing basin  14  that acts as a solvent drain  48 . 
     As seen in FIG. 2, the cover  16  is generally semi-circular in cross section and has an exterior surface  50 , an interior surface  52 , a left side  54 , a right side  56 , a rear edge  58 , and a front edge  60 . A handle  62  is attached, for instance by welding, near the front edge  60  and preferably centered on the exterior surface  50  of the cover portion  16 . The handle  62  is preferably not as wide as an average human hand, so the user will not be tempted to use the handle  62  to lift the cover portion  16  during the assembly of the portable parts washing apparatus  10  to lift the container assembly  24 , but will use the handle  62  to open the cover  16  for use. 
     The washing basin portion  14  is also generally semi-circular in cross section, but has generally planar sink bottom  64  that truncates the lowest portion of the semi-circular shape. The washing basin portion  14  has an exterior surface  66 , an interior surface  68 , a left side wall  70 , a right side wall  72 , a rear edge  74 , and a front edge  76 . A handle  78  is attached, for instance by welding, to the exterior surface  66  of the right side wall  72 , as is a handle  80  to the exterior surface  66  of the left side wall  70 . The right side handle  78  and the left side handle  80  are preferably large enough so that a typical adult can grasp the handle with both hands. Unlike the handle  62  attached to the cover  16 , the handles  78 ,  80  connected to the right  72  and left  70  side wall are intended to support the weight of the portable parts washing apparatus  10  when it is being transported from place to place. 
     The rear edge  74  of the cover portion  16  is attached for pivotal movement to the rear edge  58  of the wash basin portion  14  by a piano hinge  62 . A ball joint stud  82  is attached to the right side wall  72  of the cover portion  16  and a second ball joint stud  84  is attached to the right side wall  56  of the washing basin  14 . The studs  82 ,  84  both have a rounded ball portion  86  at their distal ends  88 . These ball portions  86  are engaged respectively by a ball joint on a top end  90  and a bottom end  92  of a gas filled piston  94 . When the portable parts washing apparatus  10  is in use, the piston  94  holds the cover portion  16  open in relation to the washing basin  14 . However, if a fire should erupt in the parts washer  10 , the upper ball stud  82  is partially made from a metal the melts well below the temperature of a solvent fire. This disconnects the upper portion  90  of the piston  94  from the right side wall  72  allowing the cover  16  to fall and smother the fire. This upper ball joint stud  82  is a form of a fusible link know in the industry. 
     Attached, for example by welding, to the outer surface of the washing basin  14  is a left leg portion  38  and a right leg portion  40 . A collar portion  42  concentrically surrounds the drain  48 . The left leg portion  38 , the right leg portion  40 , and the collar  42  all extend downwardly to the same point so that all three portions  38 ,  40 ,  42  will support the weight of the container assembly  24  and anything placed inside it when it rests on the ground. The lower edge  96  of the left leg portion  38  forms foot  98  that extends perpendicularly toward the center of the parts washing basin  14 . Similarly, the lower edge  100  of the right leg portion  40  forms foot  102  that extends perpendicularly toward the center of the parts washing basin  14 . 
     An aperture  44  is formed in approximately the center of the planar sink base  46  for a solvent outlet, or drain  48 . A second aperture  104  is formed near the right side  56  as a solvent inlet  104 . The placement of the solvent inlet  104  is not critical, but it must not interfere with the placement of the base assembly  18  when the portable parts washing apparatus  10  is configured for transport. 
     A ninety degree hydraulic elbow fitting  106  is secured in the solvent inlet aperture  104  by a pair of nuts, washers and solvent-resistant gaskets  108 . A quick-disconnect female hydraulic fitting I  10  is attached to the lower portion  112  of the ninety degree hydraulic elbow  106 . A T-connector  114  is attached to the upper portion  116  of the ninety degree hydraulic elbow  106  that is inside the wash basin  14 . A flexible metal nozzle  118  is attached to the one side of the T-connector  114  and a hose with a flow-through brush  120  is attached to the other side of the T-connector  114 . Both of the nozzle  118 , and the hose and brush  120  combination are commonly used on parts washers and are know by those knowledgeable in the art. A feature of the preferred design is that the ninety degree hydraulic fitting  106  and female quick disconnect fitting I  10  are mostly protected against impact because of its placement in the cavity formed by the right side leg  40  and its front and back braces  122 . In this position, it is easily accessible for hookup with a basin supply hose  124  with a male hydraulic quick disconnect fitting  126  on each end, while at the same time being relatively protected from any side impact. 
     A radially extending flange  128  extends perpendicularly outward from the cover portion  16  along its left side edge  54 , right side edge  56  and front edge  60 . A corresponding radially extending flange extends perpendicularly outward from the wash basin  14  portion along its left side edge  70 , right side edge  72  and front edge  76 . When the cover portion  16  is closed, the flanges  128 ,  130  align as shown in FIG. 3. A plurality of apertures  132  are formed in the cover flange  128  with a corresponding plurality of apertures  132  axial aligned in the washing basin  14  flange  130 . 
     As shown in FIG. 3A, the shaft portion  134  of a one-quarter turn fastener  136  is permanently, but rotatably attached to the cover flange  128  while the spring portion  138  of the quarter turn fastener  136  is permanently attached to the washing basin flange  130 . When the cover  16  is closed and the two flanges  128 ,  130  meet, the shaft portion  134  of the one-quarter turn fastener  136  extends through the aperture  132  in the cover flange  128 , the aperture  132  in the washing basin flange  130 , and an aperture  132  the spring portion  138  of the fastener  136 . Turning the shaft portion  134  of the one-quarter turn fastener  136  approximately one-quarter revolution with a screwdriver causes the cams  140  on the shaft portion  134  to engage the spring portion  138  from its underside to compress the spring portion  138  against the lower surface of the wash basin flange  130 . The head  142  on the shaft portion  134  of the one-quarter turn fastener  136  correspondingly compresses against the upper surface of the cover flange  128 . This secures the upper flange  128  to the lower flange  130 . 
     The sink bottom wall  46  has an underside portion  144  located opposite the side that is contained in the basin portion  146 . Attached to this sink underside portion  144 , surrounding the drain  48 , is the downwardly extending collar  42 . The collar  42  serves to position the parts washing basin  14  on the base assembly  18 , to act as a splash guard for the solvent  28  while it is being centrifuged. It also acts as a support in tandem with the right  40  and left  38  side legs when the portable parts washing apparatus  10  is configured for transport and resting on the ground or other surface. 
     In the parts washing position (FIG.  1 ), the container assembly  24  rest on a base assembly  18  with an upper rim  148  of the base assembly  18  supporting the container assembly  24  by a lower side of the container base wall  144 . Referring to FIG. 2, mounted inside the base assembly  18  by a bracket  150  is a centrifugal filter assembly  12  and a solvent transfer means  20 . The centrifugal filter assembly  12  is positioned by the bracket  150  to be directly below the solvent drain  48  in the parts washing basin  14 . There is also a solvent transport means  20  mounted inside the base assembly  18 . The solvent transfer means  20  is comprised of a pump  152 , a drive motor  154  that powers the pump  152  and the centrifugal filter assembly  12 , a solvent supply hose  156  attached to an outlet  158  of the pump  152 , a washing basin supply hose  124  and the solvent directional means  36 . In the preferred embodiment, the solvent directional means  36  is comprised of a flexible metal nozzle  118  and a brush  120  in communication with a solvent hose through which the solvent flows. Both of these solvent directional means are well know in the art. The base assembly also forms the solvent reservoir that contains the solvent for distribution by the pump. The base assembly  18  also includes a cap  160  with a compression ring  162  that is used to seal the base assembly against leakage of the solvent  28  during transport. 
     The base assembly is fabricated from an industry standard thirty-five gallon steel drum  161  modified to include a recessed housing  163  in the side of the drum  161 . This recessed housing  163  is preferably made from the same material as the drum  161  and in the preferred embodiment is fabricated and attached to the steel drum  161  by welding to form a liquid tight seal. An electrical box  164  used for water resistant applications is mounted to a rear of the recessed housing  163  where a bulkhead fitting  166  (See FIG. 6) extends through the steel drum  161  into its interior. The electrical wires  168  from the motor  154  are placed through this solvent resistant bulkhead fitting  166  into the electrical box  164  where they are wired in series with a single pole electrical switch  170  and a pig tall  172 . The pig tail  172  extends from a top wall of the electrical box  164  and has a standard three prong electrical plug  174  at its end that can be plugged into any standard three wire electrical extension cord. 
     The recessed housing  163  also contain a supply outlet  176  for the solvent  28 . A female quick disconnect type hydraulic fitting  178  is mounted to the back wall of the recessed housing  162  next to the electrical box  164 . The male attachment end  180  of the female quick disconnect  178  extends through the wall  182  of the recessed housing  162  into the interior of the base assembly  18  where its is joined to the solvent resistant supply hose  156  that is attached to the outlet side  158  of the pump  152 . A significant design benefit provided by this recessed housing  162  is the protection of both the solvent outlet quick connect  178  and the electrical box  164  and switch  170  from most damaging impacts. 
     The centrifugal filter assembly is mounted to the base assembly  18  with a mounting bracket  27 , so that a filter receptacle  184  is positioned directly below the drain  18 . The centrifugal filter assembly  12  is comprised of a filter receptacle  184  with an open top end  186 , a perforated circumferential side wall  188 , and a base  190 . The filter receptacle  184  is preferably made from a stainless steel mesh supported by an upper collar  192  and the lower filter receptacle base  190 , although other solvent resistant metals and plastics may also be used. The filter receptacle base  190  at its center has an interior upward facing cone shaped imperforate portion  194  that is surrounded by the filter side wall  188  and an exterior downward facing portion  196 . Attached to the downward facing portion  196  is a filter shaft  198 . 
     The centrifugal filter assembly  12  is mounted to the interior surface  200  of the base assembly  18  using the bracket  27  shown schematically in FIG.  6 . The mounting bracket  27  is comprised of a longitudinal member  202 , a transverse member  204 , and a bracing member  206 . A sealed bearing  208  is attached coaxial with a opening formed near the center in the longitudinal member  202 . The filter shaft  198  is placed within the sealed bearing  208  for rotational movement. A filter pulley  210  is attached to the filter shaft  198 . A second sealed bearing  212  is mounted between the transverse member  204  and the bracing member  206 . A motor shaft  214  with a pulley  216  on its top end descends through the sealed bearing  212  where it is attached to the impeller shaft of a pump motor  154 . 
     In FIG. 2, the attachment of the mounting bracket  27  to the base assembly  18  is shown. A support bracket  216  is attached, for instance by welding, to the interior of the base assembly  18 . Each bracket  216  has a hole  218  for axial alignment with holes in the ends of the longitudinal member  202  and the transverse member  204  of the mounting bracket  27 . With all the centrifugal filter assembly  12  and the solvent transfer means  20  attached to the mounting bracket  27 , the bracket  27  is lowered into the base assembly  18  and bolted to the brackets  216 . To minimize vibration, the pump will preferably rest on a resilient solvent resistant pad  220  on the bottom of the solvent reservoir  222 . 
     The motor shaft pulley  212  and the filter shaft pulley  210  are interconnected with a belt  224  so that, when energized, the motor  154  will spin the filter receptacle  184  about an axis  228  with a generally vertical orientation drawn outwardly from the interior cavity of the filter receptacle  184 . Of course, the size of the pulleys  210 ,  212 , and the rated speed of the motor  154  will control the rate of rotation of the filter receptacle  184 . The faster this rate of spin, the greater the centrifugal force that will be exerted on the solvent entering the filter receptacle  184 . Preferably, the filter receptacle  184  will spin at approximately 400 to 500 revolutions per minute. At this rate of spin, the solvent is separated from the foreign waste materials without propelling the solvent upwardly toward drain or unnecessarily atomizing it. The preferred embodiment uses a common pump  152  and motor  154  (Little Giant 3E/4E 1/5 hp) that has been modified to drive both the pump  152  and the centrifugal filter assembly  12  at the same time. The modification to the motor  154  involves using a collar to co-axially attach the extended pulley drive shaft  214  extending to the motor shaft driving the pump impeller. The electrical cover of the pump motor is also reverse one hundred eighty degrees to put the pumps electrical cord into a more convenient position. Using this slightly modified pump for both the pump  154  and the centrifugal filter assembly  12 , significantly reduces the complexity and cost of manufacturing the invention. 
     As an example of the construction of the portable parts washing apparatus  10 , the container assembly  24  with cover  16  joined to washing basin  14  that has an eighteen inch (18″) diameter and a twenty-nine inch (29″) length. The total height of the container assembly  24  is twenty-one inches (21″) including the height of the left leg  38 , right leg  40 , and collar  42 . The steel drum used for the base assembly  18  has a fourteen and one-half inch (14½″) diameter and a twenty seven inch (27″) height. Of course, the portable parts washing assembly  10  can be scaled either up or down depending on the application. For instance, a standard 55 gallon drum could be used for the base assembly if the container assembly was scaled upward accordingly. 
     The assembly of the portable parts washing apparatus  10  into the parts washing configuration and then its disassembly into the transport configuration will now be described. Referring to FIGS. 3 and 7. each of the one-quarter turn fasteners  136  is turned one quarter revolution using a standard slotted screw driver. This releases the cams from the spring portion of the connector and frees the cover  16  for upward movement. In FIG. 4, the cover  16  is lifted and the base assembly  18  is removed and placed of the ground. The cap  160  of the base assembly has been removed by loosening the compression ring  162  that secures it to the steel barrel. A filter bag  226  is inserted into the centrifugal filter  184 . 
     Using the side handles  78 ,  80  (FIG.  3 ), the container assembly  24  is lowered onto the base assembly  18  with the collar  42  inside the barrel and the basin base wall supported by the rim  148  of the base assembly  18 . The basin supply hose  124  is then removed from its storage in the washing basin  14  of the container assembly  24  and attached to the solvent supply quick disconnect  178  located in the recessed housing  163 . The other end of the basin supply hose  124  is then connected to the quick disconnect located at the solvent inlet I  10  to the washing basin  14 . The pig tail  172  is then plugged into an extension cord. The pump and centrifugal filter can then be turned on for operation using the switch  170 . Disassembly of the portable parts washing assembly  10  is essentially the reverse of the procedure just described. It should be noted that since the basin supply hose  124  and the quick disconnect fittings  126 ,  110 ,  178  are designed for hydraulic use, they will not leak solvent when removed from their complementary fittings. It is also desirable to remove the filter bag  226  during disassembly to prevent the waste materials from being reintroduced into the solvent  28 . 
     When in use, the pump  154  pumps solvent  28  from the solvent reservoir  22 , through the solvent supply hose  156 , the basin supply hose  124  and the solvent direction means  36  (through the intermediate hydraulic fittings  126 ,  110 ,  178 ). From the brush  120  and nozzle  186  assembly  36 , the solvent  28  is directed over a part to be cleaned that is placed in the parts washing basin  14 . As the part is washed, the solvent is contaminated with foreign matter. This contaminated solvent flows from the parts washing basin  14 , through the drain  48 , into the spinning centrifugal filter receptacle  184 . The spinning action of the centrifugal filter receptacle  184  employs centrifugal force to drive the solvent through a disposable filter element  226 , after which the solvent falls back into the solvent reservoir  22 . In this way, the recirculation of the solvent in the portable parts washing apparatus  10  provides a continuous flow of filtered solvent through the nozzle and hose assembly  36  to the parts washing basin  14  for the washing of dirty parts, while both drying and containing most the waste from the dirty part in the disposable filter element  226 . 
     In the preferred embodiment, two design features enable the filter receptacle to more efficiently use centrifugal force to separate the solvent from the waste. The first modification helps retain the solvent inside the filter receptacle until centrifugal force draws it through the filter media and the perforated side walls. Referring to FIG. 8, this is done by slightly slanting the mesh side wall  188  is shaped in a frusto-conical configuration upwardly and inwardly from the base to the open top end  186 . This upward and inward slant is preferably to 12 to 14 degrees from vertical inwardly toward a generally vertical axis  228 . 
     The second design feature employs a deflecting member  230  that has a top rounded center portion  232  and a downwardly extending skirt  234  that slants outwardly from the vertical axis  228 . The deflecting member  230  is attached to, or formed integrally from, the center of the interior upward facing portion of the base member  190 . The purpose of the deflecting member  230  is to direct the solvent outwardly toward the side wall  188  and away from the center of the filter receptacle  184  where the centripetal acceleration approaches zero and the solvent is less likely to be affected by the corresponding centrifugal force. During normal use, a disposable filter element  226  is draped inside the filter receptacle  184 . The upper open portion  236  of the disposable filter element  226  contains a securing means  238  that is folded over the top edge  240  of the filter receptacle  184 . The securing means  238 , for instance, can be a string or elastic fiber that is sown into a channel  242  on the upper portion of the disposable filter element  226 . The lower closed portion  244  of the filter element  226  drapes over the deflecting member  230 . 
     Preferably, the disposable filter element  226  is approximately the same size and shape as the interior of the filter receptacle  184 , so that, when the filter receptacle  226  is spinning, the walls of the disposable filter element  226  will cling to the filter side wall  188 . The disposable filter element  226  is preferably made from a fine mesh linen cloth, although other filter media would work, for instance, a heavy, permeable paper filter. The preferred embodiment of the invention presently uses a 100 micron mesh linen for its filter media. Because of the centrifugal force placed on the disposable filter element  226  during its use, the disposable filter element  226  and its contents should be mostly free of solvent. The used disposable filter element  226  can be placed in a container to be processed by a solvent service provider when it has reached the end of its useful life. This relatively small volume of hazardous waste material can be sealed in a small and light container that is mostly free of solvent and that can easily and safely be transported to a hazardous waste processing plant. The solvent remains relatively free of contaminants and may be re-used for a much greater length of time than is now possible under the state of the art. 
     A second embodiment of the present invention is shown in FIG.  9 . Components of this second embodiment which are similar to components of the first embodiment will be given like numerical designation, with an “a” suffix distinguishing those of the second embodiment. 
     This second embodiment  10   a  is substantially similar to the first embodiment, except that the motive power to rotate the centrifugal filter assembly is modified. More specifically, instead of having a drive connection through the drive shaft  214  to the pulley  212  to rotate the pulley  210 , as in the first embodiment, there is provided a turbine which is driven from the output of the pump  152   a.    
     In this second embodiment, the line  156 A from the pump  152   a  leads to a T-connection  240 . This T-connection  240  has a left branch  242  that connects to a line  244  that in turn connects to the fitting  176   a,  which in turn connects through the line  124   a  to supply liquid to the outlet tubes  36   a  at the basin. The T also has a right branch  246  that connects through a line  247  to a tubular fitting that is mounted to the support assembly for the centrifugal filter assembly  12   a.  This fitting  248  discharges liquid solvents through a nozzle  250 , with the liquid solvent stream from the nozzle  250  impinging on a turbine  252  that is connected to a drive shaft  158   a  for the filter assembly  12 . 
     In operation, when electric power is directed to the motor  154   a,  the pump  152   a  directs the liquid solvent under pressure to the T-fitting  240 . Simultaneously, the liquid solvent is delivered through the line  244  to the fitting  176   a  to in turn supply liquid solvent through the outlet tubes  36   a  and to the basin. 
     At the same time, the liquid solvent is directed through the line  247  to the fitting  248  and through the nozzle  250  to rotate the turbine  252  and cause the centrifugal filter to rotate. 
     While this invention has been described in terms of a preferred embodiment, it is contemplated that persons reading the preceding description and studying the drawing will realize various alterations, permutations and modifications thereof. It is therefore intended that the following appended claims be interpreted as including all such alterations and modifications as fall within the true spirit and scope of the present invention.