Abstract:
A low pressure hot water parts washing apparatus recirculating a heated water/detergent solution and spraying same from a perforated manifold onto oily and dirt-laden parts carried by a rotary turntable. The turntable is peripherally mounted by bearings spaced about a conical solution reservoir tank to support parts without turntable tilting. The solution is drawn from the conical reservoir tank through apertures in a radiator tube housing heating elements, the elements being cleaned by a continual flow of solution passing thereover while efficiently heating the solution.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to apparatus for washing parts to remove greases, oils and dirt, the invention particularly relating to low pressure apparatus which recirculates a water detergent solution at a relatively high temperature to spray the solution onto grime-laden parts moving on a perimeter-supported turntable mounted for rotation within the apparatus. 
     2. Description of the Prior Art 
     Apparatus intended for cleaning oils, greases and similar debris from parts such as parts removed from a vehicle engine or body when repairing the vehicle have long been known in the art. Although such apparatus are particularly useful in the washing of automotive parts, it is to be understood that parts of virtually any type which can become soiled especially by greases, oils and debris which mixes with such greases and oils can be washed with parts washing apparatus of widely varying description according to the art. Such prior apparatus typically use either an organic solvent as the washing liquid or a mixture of a detergent with water which forms an aqueous cleaning solution. Those parts washing apparatus utilizing organic solvents have become unusable in many states and municipalities due to environmental problems including disposing of the organic solvent itself Further, since such solvent washers cannot heat the solvent used for parts cleaning, the solvent must be sprayed at high pressures which can result in forcing debris of certain types into crevices and the like in certain types of parts with little prospect of removing such debris from the part. Parts washers are known which embody low pressure spraying of aqueous detergent solutions onto the parts to be cleaned, the parts being cleaned by a “flooding” process rather than by a “blasting” process. 
     While turntables have previously been used for mounting parts to be cleaned for rotary movement relative to spraying nozzles within a parts washer, the prior art has not envisioned the mounting of such a turntable about its periphery and supported by structure associated with the periphery of a conical solution reservoir, roller bearings mounted to the periphery of the conical reservoir engaging peripheral portions of the turntable to permit random location of parts, including heavy parts, on the turntable without concern for unbalancing of the turntable and thus tilting. Low pressure parts washers of the prior art typically require heating of the cleaning solution, a requirement which takes a substantial amount of time and energy. The present parts washing apparatus utilizes an extremely efficient heating element and perforated tube arrangement, the tube acting as a radiator with heated solution moving through the perforations into the conical solution tank. The heated solution is continuously recirculated and is brought in contact in each circulation cycle with heating elements disposed internally of the perforated tube. The heating elements are thus maintained in a clean condition. 
     Examples of the prior art include the parts washer disclosed in U.S. Pat. No. 5,640,981 by Niemela et al, this parts washer lacking the energy efficient heating element and radiator tube arrangement of the invention. Minkin, in U.S. Pat. No. 4,143,669, describes a parts washer having a higher powered liquid spray than does the present invention, such higher pressure sprays being used with organic solvents. In U.S. Pat. No. 5,385,159, Mead describes a parts washer having an upper tank open at the top with a sloped bottom portion which facilitates settling of sludge. 
     Accordingly, a need exists in the art for a parts washer which effectively and efficiently removes dirt in the form of caked greases, oils and debris and which uses a recirculating water and detergent solution sprayed onto soiled parts at low pressures and which is capable of cleaning soiled oily and greasy parts within a short period of exposure to the cleaning solution. The art has also suffered a long felt need for an aqueous cleaning solution parts washing apparatus whereby the solution may be heated to a desirable cleaning temperature rapidly and with energy efficiency. 
     SUMMARY OF THE INVENTION 
     The invention provides a low pressure hot water parts washing apparatus which recirculates an aqueous detergent solution between a conical solution reservoir disposed in a lowermost portion of the apparatus to a spray manifold located within an uppermost spray chamber wherein the hot solution is sprayed onto parts which are to be cleaned. The parts are placed on a perforated turntable which rotates at about three revolutions per minute relative to the spray manifold which is fixed in place within the spray chamber. The turntable is supported about its full periphery by roller bearings which are mounted about the periphery of the conical solution reservoir, it being possible to place heavy parts which are to be washed at any location of the turntable without concern for tilting of the turntable due to imbalance brought about by non-judicious placement of parts on the turntable. The turntable is driven through a sprocket and chain drive arrangement by an electric motor disposed externally of the spray chamber, the drive arrangement constituting a positive drive which avoids slippage as can occur in friction drive arrangements. 
     The spray chamber and the conical solution reservoir communicate with each other but are separated by means of removable perforated plate elements which effectively act as filters to prevent solid debris from collecting in the conical reservoir. 
     Heating elements effectively and efficiently heat the solution within the conical solution reservoir and are disposed within a tubular perforated radiator which protects the heating elements and which assists in efficient heating of the solution. Cleaning solution in its normal recirculating path through the apparatus moves from the reservoir through holes in the tubular radiator to pass by the heating elements and thus clean the heating elements on a continuous basis during washing operation. Heating element function and life are thus improved and increased by this particular cleaning solution recirculation arrangement. 
     A programmable control unit is preferably used to control the time of operation of the apparatus by turning the apparatus on and off at preselected times without the need for intervention after programming. An automatic oil skimmer is also operated by the controls, the controls further monitoring water temperature and water level. Still further, the controls monitor the lifecycles of internal components of the apparatus and indicate over time the time of operation of the apparatus. A sealing door carried by rollers movable on a track formed integrally with a lower portion of the apparatus is easily closed and opened by a user, a proximity switch being employed to indicate whether the door is open, operation of the apparatus being discontinued as long as the door is open. 
     The controls also operate a wastewater evaporation function on the command of a user, the temperature of the solution being increased on command to evaporate water from the cleaning solution, the residue of the solution simply being removed from the apparatus after water evaporation. The controls also operate automatic water fill functions and control a low-water shutoff sensor. A removable parts tree can be provided within the interior of the spray chamber for mounting of small parts during a cleaning cycle. Removable castors can be employed for rolling of the apparatus and the castors can be removed to open up channels at the lowermost portion of the apparatus which receive lift elements of a fork lift for efficient movement of the apparatus. 
     Accordingly, it is a primary object of the present invention to provide a low pressure, hot water parts washing apparatus which recirculates a heated water/detergent solution within the apparatus and sprays the solution onto oily and dirt-laden parts moving relative to a perforated spray manifold on a rotary turntable, the aqueous solution being sprayed at low pressure through perforations in the manifold at low pressure. 
     Another object of the invention is to provide a parts washing apparatus operable at low pressure wherein parts mounted on a rotary turntable are cleaned by a low pressure spray of aqueous cleaning solution, the turntable being mounted for rotation by roller bearings fixedly mounted about an upper periphery of a conical solution reservoir within which the cleaning solution is heated and to which the cleaning solution is drained after spraying. 
     It is yet another object of the invention to provide a parts washing apparatus which recirculates a heated water/detergent solution into contact with parts which are to be cleaned and a solution heating chamber within which the solution is heated by heating elements disposed within a perforated tube which acts as a radiator to facilitate heating of the solution and which allows cleaning solution to be drawn into the interior of the tube and into contacting relationship with the heating elements so that the heating elements are continuously subjected to the cleaning action of the recirculated cleaning solution. 
     Further objects and advantages of the invention will become more readily apparent in light of the following detailed description of the preferred embodiments. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the parts washing apparatus of the invention shown in an operating condition with the door closed; 
     FIG. 2 is a perspective view of the parts washing apparatus of the invention shown with the door fully opened and without the screen elements in place; 
     FIG. 3 is a sectional view of the apparatus of FIG. 2; 
     FIG. 4 is a detail view of sealing elements used to facilitate sealing of the door to the main body of the apparatus; 
     FIG. 5 is a perspective view of interior portions of a cleaning chamber of the apparatus shown without a turntable in place and without screen elements in place; 
     FIG. 6 is a perspective view of the cleaning chamber of the apparatus shown with the turntable in place but without screen elements in place; 
     FIG. 7 is a partially exploded view of the apparatus with the exterior shell or cabinet removed; 
     FIG. 8 is a perspective view of a conical cleaning solution reservoir tank without peripheral shoulder portions including a reservoir tube and heating elements shown removed from the apparatus and partially cut-away; 
     FIG. 9 is a schematic of plumbing and electrical subsystems including connections to a control panel and to each other; and, 
     FIG. 10 is a plan view of the screen elements which are to be disposed between the washing chamber of the apparatus and the conical cleaning solution reservoir tank, the screen elements comprising a filter. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings and particularly to FIGS. 1 and 2, a parts washing apparatus  10  configured according to the invention is seen to comprise an upper cabinet  12  and a lower cabinet  14 , the upper cabinet  12  defining a cleaning chamber  18  as is seen in FIG.  2  and also in FIG. 6, the cleaning chamber  18  being substantially cylindrical on closure of door  100 . In essence, the combination of the upper cabinet  12  and the door  100  causes the upper cabinet  12  to take a cylindrical conformation. The lower cabinet  14  essentially comprises a cylindrical body portion of the apparatus  10  which is slightly greater in diameter than the diameter of the upper cabinet  12 . The lower cabinet  14  essentially comprises a housing for apparatus sub-systems including plumbing and electrical sub-systems which are controlled as will be described hereinafter to cause a heated aqueous cleaning solution to be sprayed at low pressure onto parts (not shown) which are to be cleaned of oils, greases, etc., within the cleaning chamber  18 . An access panel (not shown) covers an opening (not shown) in the lower cabinet  14 , the access panel in a conventional manner being removable in order to gain access to components of the apparatus  10  housed by the lower cabinet  14 . 
     The upper cabinet  12  and the lower cabinet  14 , along with most of the other metal components comprising the apparatus  10  are formed of stainless steel in order to provide a structure of particularly high quality which provides an increased operating lifetime especially with use of high temperature water and detergent cleaning solutions. The use of stainless steel to fabricate the apparatus  10  or at least major portions of it and particularly those portions which come in contact with hot cleaning solution provides an effective useable lifetime for the apparatus  10  which is substantially greater than is to be expected with ordinary carbon steel or similar materials most often used in the construction of parts washing apparatus. The cabinets  12 ,  14  are typically formed of fourteen gauge stainless steel and can be formed with cleaning chambers of differing sizes and parts capacities of differing weight and cleaning chamber dimensions. 
     It is to be noted that the apparatus  10  is conveniently sized in order to provide a work surface height, that is, the height of the opening in the upper cabinet  12 , so that an individual loading parts into the apparatus  10  loads at waist level in order to reduce the possibility of back strain. 
     A manifold  20  having perforations  22  along its length is seen in FIG. 2 inter alia to be formed of vertical legs  24 ,  26 , an upper horizontal bight portion  28  and a horizontally disposed terminal portion  30 . The perforations  22  extend substantially along the full length of the manifold  20  and are positioned thereon in order to direct a spray of a cleaning solution into central portions of the interior of the cleaning chamber  18 . The vertical leg  24  of the manifold  20  is connected as will be described hereinafter to plumbing apparatus housed within the lower cabinet  14 , cleaning liquid being forced under relatively low pressure such as about 11 psi through the manifold  20  and out of the perforations  22  into the interior of the cleaning chamber  18 . The manifold  20  is maintained in a fixed position within the cleaning chamber  18 . The terminal portion  30  of the manifold  20  is disposed in a position which is below the parts which are to be cleaned as will be seen from description yet to be provided. 
     The upper cabinet  12  is further provided with a vent  32  which allows escape of heated water vapor and steam, the vent  32  acting in a manner similar to the function of a pressure relief valve although low pressures are employed within the cleaning chamber  18 . 
     A conventional oil skimmer apparatus  34  including a fall-level indicator (not shown) is mounted to the apparatus  10  at a convenient location, the skimmer preferably being of the plate-type which is conventional in the art and which includes a motor (not shown) which drives a plate to skim oil from cleaning solution passed through the skimmer  34  an appropriate time after shut down of the cleaning function of the apparatus  10 . Essentially, the apparatus  10  is shut down after a day&#39;s operation and the oil skimmer  34  is caused to operate beginning about one hour after apparatus shutdown. The skimmer  34  can be provided with a reservoir at  35  into which relatively large sludge-like particles of hydrocarbons and the like can be deposited. 
     A motor  36  mounted to the upper cabinet  12  exteriorly of the apparatus  10  is covered by a hood  47 , the motor  36  best being seen in FIG.  7  and acting to drive a sprocket  40  mounted at a lower central portion of the cleaning chamber  18  by a stub shaft  41  which is in turn mounted for rotation by structural spokes  43  extending in regular fashion from the perimeter of conical cleaning solution reservoir tank  52 . The spokes  43  are substantially flat, elongated elements which connect to a cylindrical hub  45  through which the stub shaft  41  extends and is thereby mounted. The stub shaft  41  mounts a toothed sprocket  40  immediately above the hub  45 , the sprocket  40  being driven by a chain  42  which extends through an opening (not shown) in a side wall of the upper cabinet  12  and into mechanical contact with the motor  36 , the motor  36  driving the sprocket  40  by means of the chain  42 . The opening through which the chain  42  extends is covered by the hood  47 . The sprocket  40  is provided with a diametrically disposed bar element  49 . On rotation of the sprocket  40 , the bar element  49  is caused to rotate at approximately 3 to 6 revolutions per minute, surfaces of the bar element  49  coming into corresponding contact with camming pads  53  mounted to the underside of a turntable  38 , thereby to rotate the turntable  38 . 
     It is to be understood that the turntable  38  can be utilized to mount parts which are to be washed. A conventional parts tree (not shown) can be mounted to the turntable in order to hold parts which can best be washed through the use of such ancillary apparatus as contemplated. The turntable  38  can be formed of an upper ring  44 , a lower ring  46  with expanded mesh side walls  48  joining the rings  44 ,  46  about opposing peripheral undersurfaces thereof, a bottom  50  of the turntable  38  being fixed to the lower ring  46  in a conventional manner. It is to be understood that turntables such as the turntable  38  exist which are of conventional design although it is to be understood that modifications may be made to the turntable  38  which facilitates functioning with other structure to cause the apparatus to be operable, such as the camming pads  53 . 
     A conical cleaning solution reservoir tank  52  is seen in FIG. 2 inter alia to be conically shaped with the putative apex of the cone being disposed downwardly within the apparatus  10 , a circular periphery of the base of the conical tank  52  being upwardly disposed and being essentially turned outwardly about its periphery and welded to upper peripheral portions of the lower cabinet  14 . The connection between the lower cabinet  14  and the conical tank  52  is caused to have substantial strength since this combination of structure is intended to support the turntable  38  and the hundreds of pounds of parts which are to be placed on the turntable  38  for washing. 
     In order to prevent unbalancing of the turntable  38  such as can occur in other parts washing apparatus, the turntable  38  is mounted in the present apparatus  10  for rotation on bearings  58  which contact periphery  54  of the lower ring  46  comprising the turntable  38 . The bearings  58  are mounted for rotation by bearing mounts  60  which are fixed to peripheral portions of the conical tank  52 . The spokes  43  mounting the hub  45  and the stub shaft  41  which in turn mounts the sprocket  40  and the turntable  38  are seen to extend from the mount  60  to the hub  45 , the spokes  43  being fixed at each end respectively to said mount  60  and to the said hub  45 . The bearings  58  positively support the turntable  38  for rotary motion within the cleaning chamber  18  without tilting of the turntable  38  such as can occur with turntables of prior parts washing apparatus due to injudicious placement of parts which are to be cleaned on these prior art turntables. Turntables supported at their center by means of a shaft only are subject to tilting of the turntable which usually causes the apparatus to shut down or sustain damage. The present parts washing apparatus  10  in use functions properly regardless of the location on the turntable  38  occupied by the parts which are to be cleaned. 
     Perforated screen elements  56 , seen best in FIG. 10, are placed over the spokes  43  and have apertures  55  which mate with pins  57  which extend upwardly from upper surfaces of each of the spokes  43 . The pins  57  received within the apertures  55  of the screen elements  56  cause said screened elements  56  to stay in their proper location, thereby to form a continuous screen between the cleaning chamber  18  and the interior of the conical reservoir tank  52 . The screen or filter formed by the perforated screen elements  56  prevent rough debris and other unwanted materials from falling into the interior of the reservoir tank  52 . Further, at initial operation of the apparatus  10 , detergent is placed for dissolution onto the screen elements  56 . 
     The conical cleaning solution reservoir tank  52 , which is best seen in FIGS. 5 through 8, is seen to be substantially conical in conformation as has been indicated previously, the conical body of the tank  52  having a radiator tube  62  extending through aligned openings formed in the tank  52  and extending outwardly of the tank  52  at each end of the tube  62 . The radiator tube  62  is closed at either end by respective end plates  70  and  72 , the end plates  70 ,  72  and the ends of the radiator tube  62  extending externally of the conical reservoir tank  52  and being flush fit and effectively sealed at the openings mentioned above but not expressly shown which are formed in the tank  52  for receipt of the tube  62  therethrough. The radiator tube  62  is provided with a plurality of holes  64  through which cleaning solution passes from the interior of the tank  52 , the holes  64  being formed only in that portion of the tube  62  lying within the confines of the tank  52 . Heating elements  66  and  68  are mounted by the end plate  70 , the heating elements  66 ,  68  essentially being conventional hot water heating elements, said elements being conventionally fitted to the end plate  70  at which location electrical connections  74  connect with the heating elements  66 ,  68 . The heating elements  66 ,  68  are preferably 4500 watt heating elements and act to efficiently and effectively heat cleaning solution within the tank  52  with substantial energy efficiency. Cleaning solution sprayed through the manifold  20  within the cleaning chamber  18  moves downwardly by gravity into the conical tank  52  and through the holes  64  in the radiator tube  62  to contact the heating elements  66 ,  68  and thereby continuously clean said heating elements  66 ,  68  during operation of the parts washing apparatus  10 . Essentially, the only path which the cleaning solution can follow for recirculation is through the radiator tube  62  and into contact with the heating elements  66 ,  68 . The radiator tube  62  further enhances energy efficiency by heating of the cleaning solution within the conical tank  52  by radiation of heat to the solution from the radiator tube  62 . 
     Heated cleaning solution is drawn from that end of the radiator tube  62  which is sealed by the end plate  72 , the end plate  72  having a fitting  76  mounted thereto at one end and to one end of a hose  82  which extends between the fitting  76  and pump  78  which is driven by motor  80  in a direct-drive manner which is conventional in the art. The pump  78  thus draws heated cleaning solution from the tank  52  on the suction side of said pump  78 . Cleaning solution then goes through the pressure side of the pump  78  which has a fitting  84  disposed between the pump  78  and a hose  86  which connects to a fitting  88  formed on an end of the manifold  20  such that the cleaning solution on the pressure side of the pump  78  is forced upwardly into the manifold and sprayed through the manifold at a relatively low pressure. 
     The combination of the radiator tube  62  with the conical tank  52  has particular advantages which are not readily obvious. Shaping the solution-holding tank as a cone can be appreciated in its own right as providing several advantages. For example, the quantity of solution employed is less with the conical tank than with a cylindrical tank having the same base and height. With a smaller quantity of solution to heat, energy efficiencies are inherently present. Further, the lowermost portion of the tank  52  takes the shape of the apex of a cone since the conical tank  52  is inverted. For that reason, the tank  52  can be cleaned much more easily than can a cylindrical tank, a tank shaped as a rectangular solid or any other known tank. A temperature sensor  61  placed on a wall surface of the tank  52  at a location just below or near the projected lower portions of the tube  62  can provide an indication of the need to clean the tank  52 . Once sludge gathers in the bottom of the tank  52  to a level covering the sensor  61 , the sensor  61  will not read a temperature which is as high as the temperature of the solution in upper portions of the tank  52 , thereby indicating that the quantity of sludge materials present in the tank  51  has reached a point at least up to and possibly contacting lower portions of the tube  62  depending on the location of the sensor  61 . Temperature difference measurements can be taken relative to a comparison of the temperature read by the sensor  61  and by any sensor detecting the temperature of the solution. 
     The holes  64  formed in the radiator tube  62  are conveniently taken to be 11-64ths of an inch in diameter although the hole diameter can vary. However, it is to be understood that a relatively small hole diameter is desirable in order to prevent a vortex flow of the solution within the tank  52  during recirculation of the solution. In practice, the number of the holes  64  increase from the pump intake side of the tube  62  toward the other end of the tube  62 . Thus, there will typically be at least twice as many of the holes  64  at the end opposite the pump intake side of the tube  62  as are present at the pump intake side. Such an arrangement of the holes  64  permits a pulling of the solution by the pump  78  from all portions of the tank  52  at least above the tube  62  rather than the creation of one or more vortex flow patterns which would occur with a few large holes. In a vortex flow pattern, only a portion of the solution would be recirculated. The holes  64  are also seen to be formed only over the “top” half to two-thirds of the tube  62  such that the lower portions of the tube  62  are not perforated. This selective perforation of the tube  62  minimizes the tendency to draw sludge present in the lower portion of the tank  52  up into the tube  62  especially on start-up of the apparatus when the pump  78  is first activated. 
     The shape of the tank  52  further provides for heating efficiency, heat being transferred to the solution through the radiating effect of the tube  62  upwardly into the solution with heat flow curving outwardly at top portions of the solution toward upper walls of the tank  52 . Thus, a heat flow is created around the tank in a pattern whereby upward flow of heat first occurs, the flow cascading outwardly and then downwardly to efficiently heat the solution present throughout the upper portions of the tank  52  and particularly including the solution about the upper periphery of the tank  52 . Heated water moves in this flow pattern to be increasingly heated as the flow continues and to thus reach a desired solution temperature rapidly and with substantial energy efficiency. 
     Temperature sensors  92 ,  94 ,  96  are mounted in a wall of the tank  52  and connect to appropriate controls which are to be described hereinafter. First sensor  92  senses the temperature of the cleaning solution within a temperature range of 170° to 180° F. for normal cleaning operation, the sensor  92  through appropriate controls shutting off the heating elements  66 ,  68  once water temperature attains the desired temperature. The second sensor  94  is caused to operate in a mode to cause a wastewater evaporation function, the sensor  94  causing the heating elements  66 ,  68  to heat the cleaning solution to a temperature of up to 210 to 212° F. so that the cleaning solution evaporates leaving a residue which can be cleaned from the lower portion of the conical tank  52 . The parts washing function cannot operate when the apparatus  10  is controlled through the sensor  94 . The third sensor  96  allows heating of the cleaning solution to 140° F., an indication of this temperature allowing a user to realize that detergent may be added to the apparatus  10  without producing a foaming problem. Conventional electrical connections connect the sensors  92 ,  94  and  96  to appropriate controls for selection of the necessary function. 
     A low water level control sensor  98  is mounted to a wall of the conical tank  52  for indication of a minimum water level within the tank  52  at which parts washing can commence. Since powder detergents are approximately 90 to 95% inert, that is, fillers such as soda ash and the like, these detergents will not dissolve below a temperature of 140° F. and would drop to the bottom of the tank  52  in the event that inappropriate operating temperature, that is a detergent solubilizing temperature, had not been reached prior to distribution of the detergent within the interior of the cleaning chamber  18 . The powder detergent is simply thrown over the screen elements  56  when temperature of the water or cleaning solution within the tank  52  reaches a temperature of 140° F. The low level control sensor  98  is a part of a conventional water level control apparatus utilized to provide the desired function within the apparatus  10 . 
     The door  100  of the upper cabinet  12  is arcuate in shape in the manner in which a portion of the periphery of a cylinder is cut from the cylinder, the door  100  on full closure essentially forming a cylinder with remaining portions of the upper cabinet  12 . The door  100  moves on rollers  102  attached to upper and lower horizontal side edges of the door  100 , the rollers  102  moving on tracklike elements which comprise lips  104  of channels  106  which are formed along horizontal edge portions of the door opening of the upper cabinet  12 . A channel  105  which is disposed vertically at said door opening receives the forward edge of the door  104  therewithin and seals the door  100  by means of a brush seal  112 . The door  100  is seen to be provided with a plate element  108  (seen only in FIG. 9) which contacts a proximity switch  110  mounted to the upper cabinet at the door opening so that it can be determined that the door  100  is fully moved in place to cover the door opening and thus close and seal the apparatus  10 . A door interlock  111  can further be provided to prevent opening of the door  100  immediately after cleaning of parts. The interlock  111  can take the form of a variety of conventional interlock mechanisms such as a solenoid-operated pin lock which prevents opening of the door  100  until interior temperatures have fallen to a level whereby the door  100  can be opened without subjecting an operator to steam and vapors at potentially dangerous temperatures. The interlock may be timed or may be responsive to temperatures within the interior of the upper cabinet  12 . Brush seals  114  are also respectively located horizontal along edges of the door  100  in order to provide sealing functions. The forward edge of the door  100  fits within the U-shaped channel  105  which is formed along the door opening in a vertical sense to receive the forward edge of the door  100 . The door  100  is conveniently provided with a handle  122  to allow manual opening and closing of the door  100 . A control box  124  is conveniently mounted to a side wall of the apparatus  10  externally thereof, the control box having a seven day/twenty-four hour programmable timer and a Siemens PLC programming unit  125  (see FIG. 9) which allows programming of controls to turn the apparatus  10  on and off, fill the apparatus  10  with water, monitor the life cycles of all components of the apparatus  10 , monitor and cause to function the turntable motor  36 , the motor of the oil skimmer  34 , heating elements  66 ,  68 , etc. and to indicate the length of time that the apparatus  10  is operated over a given period of time. Controls (not shown) inside the control box  124  are programmable to produce a desired functioning of the apparatus  10 . It is to be understood, however, that the functioning of the apparatus  10  can be embodied in a hardwired arrangement (not shown) to produce all desired functions necessary for operation of the apparatus  10 . 
     The apparatus  10  can be seen to be provided with casters (not shown) mounted to undersurfaces of the lower cabinet  14 . The casters can be used to roll the apparatus  10  easily to desired locations. Channels (not shown) can be formed in a lowermost surface of the lower cabinet  14  to provide entryways for lifting of the apparatus  10  such as by a fork-lift truck or the like. 
     Certain features of the apparatus  10  described herein should be emphasized. The positive drive arrangement formed by the sprocket  40  and the chain  42  driven by the motor  36  is utilized to prevent slippage inherent in many turntable drive arrangements of the prior art. In the present invention, slippage does not occur during drive of the turntable  38 . 
     Further, it is desirable to maintain the heating elements  66 ,  68  in as clean a condition as possible. Accordingly, the heating elements  66 ,  68  are placed inside the radiator tube  62  whereby the heated cleaning solution is recirculated past and in contact with the heating elements  66 ,  68  so that said heating elements are continuously cleaned during operation of the apparatus  10 . 
     Further, the parts washing apparatus  10  functions without the necessity for tying down small parts or the like which could be dislodged from a parts tree or from the turntable  38 , cleaning solution being sprayed through the manifold  20  at low pressure of approximately 11 psi so that parts to be cleaned and particularly including small parts to be cleaned, are not dislodged from the turntable  38  on subjection thereof to a flow of cleaning liquid thereagainst. 
     It is therefore to be seen that the apparatus  10  of the invention can be configured in ways other than as explicitly described herein, the scope of the invention being defined by the scope of the recitations of the appended claims.