US3242057A

US3242057A - Rotary drum degreaser

Info

Publication number: US3242057A
Application number: US195214A
Authority: US
Inventors: Stephen J Talian; Harry J Hanft
Original assignee: Metalwash Machinery Co
Current assignee: Metalwash Machinery Co
Priority date: 1962-05-16
Filing date: 1962-05-16
Publication date: 1966-03-22
Anticipated expiration: 1983-03-22

Description

5 Sheets-Sheet 1 \wm vwm RY DRUM DEGREASER S. J. TALKAN ETAL.

a y IIIIIIIIIIII Frill March 22, 1966 Filed May 16, 196;?

gre 'l x z /l L/nA/ BY Ham er JAM/VA?- W 5% ATTORNEYS March 22, 1966 5, J, TALIAN ETAL 3,242,057

ROTARY DRUM DEGREASER Filed May 16, 1962 5 Sheets-Sheet 2 & N so 0 ATTO R N EYS S. J. TALIAN ETAL Filed May 16, 1962 ROTARY DRUM DEGREASER 5 Sheets-Sheet 3 ATTORNEYS March 22, 1966 5. J. TALIAN ETAL 3,242,057

ROTARY DRUM DEGREASER Filed May 16, 1962 5 Sheets-Sheet 4 k VINVEN ORS 5 5 STiPHEA Tum/v B Ham? Y uT/m/vr-r ATTO RN EYS March 22, 1965 5 TALIAN ETAL 3,242,057

ROTARY DRUM DEGREASER Filed May 16, 1962 5 Sheets-Sheet 5 INVENTORS TE'PMENIIZ'QL/AN A QPQY JA Awrr ATTO R N EYS United States Patent 3,242,057 ROTARY DRUM DEGREASER Stephen J. Talian, Bayonne, and Harry J. Hanft, Union, N.J., assignors to Metalwash Machinery Company, Elizabeth, N..l., a co-partnership Filed May 16, 1962, Ser. No. 195,214 11 Claims. (Cl. 202170) This invention relates to vapor degreasers in general and in particular to improvements in vapor degreasers of the type having a conveyor means passing therethrough wherein a tendency exists for the conveyor means to transport the solvent vapors from within the degreaser housing to outside of the housing.

While the present invention is described in its preferred embodiment employing an inclined helical drum conveyor, those skilled in the art will readily appreciate that the invention is equally applicable to degreasers employing screw or other conveyor systems.

In degreasers, it is customary to employ a tank or housing having a liquid reservoir of solvent or treating material in a lower portion which may be vaporized by suitable heat means. The solvents generally employed are those which have a vapor heavier than air, and as the solvent is vaporized by the heating means, the vapor rises to an intermediate level within the housing whereupon the vapors are condensed by a suitable water jacket and/or condensing coils at the maximum desired level. While the solvents and their vapors generally used in typical degreasing applications are non-flammable, such as trichlorethylene, etc., their vapors are both expensive as well as being highly toxic. Therefore, for cost reasons as well as for safety reasons, none of the vapors within the degreasers housing should be allowed to escape therefrom.

In degreasers having a continuously moving conveyor therethrough the problem of stripping and condensing all of the solvent vapors from the articles as they are conveyed out of the degreaser by the conveyor has been a continual design problem. In conveyors of the type having an inclined helical drum or screw conveyor therein, the problem has been particularly severe because of the tendency of the helical thread of the conveyor to discharge the vapor directly along with the degreased articles.

The present invention is directed toward a novel means for preventing escape of volatile vapors from the delivery end of the conveyor means. The invention includes an auxiliary condensing means adapted to encircle the discharge end of the helical conveyor and condense any vapor therein to prevent its discharge therefrom. Vapor in rotating drum conveyors is forced upwardly by the action of the conveyor above the normal condensation level within the degreaser housing because the vapor within the drum is effectively shielded from the main condensing means about the periphery of the housing. Heretofore, because of the nature of this type conveyor, escape of volatile vapors from the end thereof has always been a problem. Applicants arrangement has provided a novel and successful solution of this problem.

In the described preferred embodiment of the invention, articles to be treated are subjected to a three way cleaning action including emersion within the liquid solvent at the lower end of the revolving drum, thereafter the vapor phase thereabove and continuous tumbling to degrease all varieties of small parts including hard to clean shapes such as cups, etc.

Accordingly it is an object of the present invention to provide a continuous flow conveyor degreaser having improved vapor condensing means.

Another object of the invention is to provide a rotary drum conveyor degreaser wherein the articles to be de- 'ice greased are first subjected to an immersion within the solvent and thereafter pass through the solvent vapor while being tumbled.

Another object of the invention is to provide a novel water cooled annular condensing trough about the discharge throat of a drum conveyor.

Yet another object of the invention is to provide a degreaser having a conveyor adapted to transport articles therethrough wherein a minimum of solvent and solvent vapor is discharged with the articles from said degreaser.

A further object of the invention is to provide an automatic degreaser which is extremely compact and simple in design, inexpensive to manufacture, reliable and trouble free in operation and employs a minimum of parts.

These and other objects and advantages of the invention will become apparent and the invention will be fully understood from the following description and drawings in which:

FIG. 1 is a side elevational view of a degreaser accord ing to the invention;

FIG. 2 is a top plan view of the apparatus as shown in FIG. 1;

FIG. 3 is a horizontal sectional view taken along line 33 of FIG. 1;

FIG. 4 is an enlarged partial sectional view of the discharge end of the revolving drum conveyor showing the drum discharge condensing means;

FIG. 5 is a cross-sectional view of the invention taken along line 55 of FIG. 4; and

FIG. 6 is a perspective view of the invention, with. portions broken away, schematically showing the condensing means conduit inter-connections.

The apparatus shown in the figures includes a housing 10 having a loading chute 12 and a discharge chute 14 attached to opposite ends thereof. Small articles, such as those indicated at 16 may be deposited in the loading chute 12 and will fall by gravity to the interior of the housing 10 into a connecting chute 18 which communicates with the lower end of an inclined drum conveyor means 20. The conveyor drum 20 is rotationally supported at its upper and lower ends by suitable rotary supports shown generally at 34. A drum drive means 22 includes a motor 24 connected through a reduction gear box 25, and chain 26 to a sprocket 28; afiixed to the upper end of the drum 20. Aflixed to the interior wall of the drum 20 is a helical or spiral baflie 30 (FIG. 4) which contains the proper pitch to effectively transport the articles 16 as they are deposited at the lower end of the drum 20 up through the drum to the discharge end of the drum and into the unloading chute 14.

Disposed in the lower portion of the housing 10 is a solvent boiling chamber 36 heated by a suitable internal heating coil 38 through which steam or other heating medium may be passed. Adjacent the boiling chamber 36 is a solvent dip chamber 40 Whose normal upper level of solvent is determined by the upper edge of a partition or dam member 48. Accordingly, any excess liquid entering the dip chamber 40 will flow over the upper edge of the dam 48 into the solvent boiling chamber 36 which is generally maintained at a lower level. The heating coils 38 function to boil the liquid solvent in the chamber 36 and create a vapor in the area thereabove. As this vapor is generally of a density greater than air it will tend to remain in the lower portion of the housing 10. However to prevent excess rise of the level of this vapor, condensing means are employed in the form of an exterior water jacket 44 and interior condensing coils 46a and 46b disposed on opposite interior walls of said housing. Cool liquid, such as water, is obtained from a pair of supply conduits 94 and circulated through water jacket 44 and coils 46a and 46b to establish an upper level limit 42 for the volatile vapors. The cool condensing liquid flowing through coil 46a is discharged into a conduit 72 for purposes later explained. The liquid leaving coil 46!) passes through a conduit 82 to fill the space between

inclined plates

78 and 80. A rectangular aperture 96 in the degreaser side wall between the

plates

78 and 80 permits the condensing liquid therebetween to flow into the water jacket 44. A baflie 98 in the jacket 44 establishes a circular fluid flow path therein after which the condensing fluid is discharged through opening 100 to a suitable drain (not shown). Accordingly, as the vapors rising from the boiling chamber 36 build up to the region of the water jacket 44 they will be cooled and condensed whereupon they will fall upon a horizontally extending drainage plate 50 projecting inwardly from the inside wall of the housing 10. The drainage plate 50 is suitably pitched and includes an edge lip 51 so that the condensed vapor will flow by gravity toward the collection conduit 52 of a separator 54, see FIG. 3. If the upper level of the solvent vapors reach the horizontal level of sensor means 39 in the side of the chamber, the control means 41 is efiective to reduce the heat input to coils38 to reduce the boiling rate of the solvent in chamber 36.

The separator 54 functions to separate any condensed water vapor from the condensed solvent so that the water vapor may be removed and not returned to the solvent dip chamber 40. The separator includes an internal baflie plate 56 depending downwardly from a top portion thereof to the proximity of the lower boundary of the separator 54. Therefore as the condensed fluids enter the right hand portion of the separator 54 (FIG. 1) via the inlet conduit 52, any water therein will collect in the area 57 because of its being a lighter fluid than typical solvents such as trichlorethylene. As required, the water from the area 57 may be periodically drained through valve means 60. The heavier condensed solvent will pass beneath the lower edge of the plate 56 to the left side of the separator 54 and is returned through a suitable conduit 58 to the interior of the housing to replenish the solvent in the dip chamber 40.

Referring to the upper end of the drum conveyor means 20 which is best shown in FIG. 4, three spaced annular flanges 66 are aflixed to the drum outer periphery. These flanges 66 cooperate with upper and lower semi-circular arcuate baffles respectively 62 and 64 to provide a labyrinth seal between the vapor degreasing chamber 68 and the discharge chamber 70. The portion of the drum 20 within the chamber 68 is provided with a plurality of spaced apertures 32 to allow free entry and exit of degreasing vapors about the articles tumbling therein. That portion of the drum 20 within the chamber 70 is without apertures so that cool condensing water flowing thereover from a spray head or nozzle 74 will not enter the interior of the drum to contaminate and thereby mix with the solvent in the lower portion of the housing. The condensing liquid emitted from the nozzle 74 may be obtained from any suitable cold water source such as conduit 72 leading from the discharge end of condensing coil 46a (FIG. 6). However, it should be appreciated that such a series arrangement between the condenser coils 46 and the nozzle 74 is merely a matter of expediency in order to conserve the use of condensing water. The cold water emitted from the nozzle 74 descends over the aperture free upper periphery of the inclined drum 20 and collects thereabouts in an annular cold water ring 77 defined by a surface of the left baffles 66 of FIG. 4 and a cylindrical collar '76. The cylindrical collar 76 thereby cooperates with the latter element 66 and the drum 20 to form a rotating annular trough about the discharge throat of the cylinder which is continuously fed with a cold liquid from the nozzle 74. Accordingly, those degreasing vapors that have a tendency to be fed by the helical baffle up the interior of the drum 20 and out the discharge end of the drum along with the articles 16 will be condensed by this cool condensing annular ring 77.

The discharge chamber 70 is further cooled and insulated from the hot solvent vapors in the chamber 68 by a lower inclined drainage plate 78. The plate 78 directs the overflow liquids from the lower portion of the water ring 77 exteriorally of the housing 10 through a suitable drain opening 84. A second inclined plate 80, spaced from the uppermost inclined drainage plate 78 forms a chamber therebetween. As shown in FIGS. 4 and 6, the space between

plates

78 and 80 is supplied with cold condenser water from the discharge of the coil 46b to thereby cool the lowermost inclined portion of the chamber 70 and enhance its condensing effect upon the discharge throat of the drum 20. The helical baffle 30 contains along its outer peripheral edge a plurality of apertures 86 which permit the drainage of the condensed solvent vapor down the inclined slope of the drum 20 so that the vapors condensing within the drum may drain downwardly and through the drum apertures 32 into the solvent chambers 36 and 40.

The upper side of the housing 10 is provided with a pair of suitable access doors 88 to facilitate entrance to the interior of the chamber for maintenance as well as cleaning purposes. Disposed between the access doors 88 is a vent stack 90 which may be provided with blower means 92 to create a slight negative pressure within the housing 10 so that the air flow at the loading and discharge chutes 12 and 14 will be inward toward the interior of the housing rather than outward therefrom to further insure against the escape of the highly toxic solvent vapors into the adjoining work area.

While the present invention has been described as relating primarily to a degreasing apparatus employing a solvent such as trichlorethylene, those skilled in the art will readily appreciate that applicants novel arrangement and condenser means could be employed to great advantage or arrangements for the vapor treating of articles upon a conveyor not necessarily in need of degreasing. Furthermore, while applicant has described his invention as being particularly suitable to the condensation of vapors at the throat of a rotary drum conveyor, it will be readily appreciated that the invention is equally applicable for condensing vapors that would be carried by an inclined bucket conveyor or screw conveyor.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invent-ion may be embodied in many other ways differing from those suggestions listed above without departing from such principles.

What is claimed is:

1. A rotary drum degreaser comprising a housing having top and bottom walls and opposed inlet and outlet end walls each extending between said top and bottom walls, means for vaporizing a liquid, whose vapor is heavier than air, held in a lower portion of said housing, first condensing means for condensing the vapor at a predetermined level intermediate the top and bottom walls of said housing, apertured cylindrical drum conveyor means rotatably mounted within said housing, said drum conveyor means being inclined upwardly toward said outlet end wall of said housing and having a lower end portion adjacent inlet and walls of said housing adapted to extend into the liquid held in the lower portion of said housing, and an upper discharge end portion adjacent said outlet end wall of said housing terminating above the predetermined vapor condensing level, means for rotating said drum conveyor means to obtain a direction of feed of said articles therein from the lower end portion to the upper discharge end portion thereof, means extending between said inlet end wall of said housing and said lower end portion of said conveyor means for directing articles from said inlet end Wall of said housing to said lower end portion of said conveyor means, means at said outlet end wall of said housing for receiving articles from said discharge end portion of said conveyor means, and second condensing means about the upper discharge portion of said drum conveyor means for condensing the vapors therein and thereby prevent discharge of said vapors from the upper portion of said drum conveyor means.

2. Apparatus according to claim 1 wherein said drum conveyor means includes spiral screw bai'He means having apertures therethrough to permit flow by gravity of liquid therein to a lower portion of said housing.

3. Apparatus according to claim 2 including inclined drainage plate means afiixed from an interior wall of said housing surrounding said drum conveyor means at a level below the level of said first condensing means for collecting vapors condensed thereby.

4. Apparatus according to claim 3 including separation means operatively associated with said drainage plate means for removing water from said condensed vapor.

5. Apparatus according to claim 2 wherein said second condensing means includes inclined plate means, said plate means having a doubled walled portion for receiving condensing liquid therebetween.

6. In a degreaser for degreasing articles at least partly with volatile vapors, an inclined rotary helical conveyor having a lower article-receiving end and an upper articledischarging end, liquid-retaining means surrounding the upper article-discharging end of said conveyor for retaining an annular ring of cool condensing liquid surrounding and in engagement with said conveyor, and means for continuously supplying relativley cool condensing liquid to said liquid-retaining means.

7. In a degreaser as recited in claim 6, said liquidretaining means surrounding the article-discharging end of said conveyor being carried. by and rotatable with said conveyor.

8. In a degreaser as recited in claim 6, said inclined helical conveyor having a rotary cylindrical housing and said liquid-retaining means including an annular flange attached to the exterior of said housing and extending radially outward therefrom, and a cylindrical collar coaxial with said housing and afiixed at one end to said flange to form an annular trough about said housing, said means for supplying a cool condensing liquid directing the liquid into an upper portion of said trough.

9. In a degreaser for at least partly degreasing articles with volatile vapors, an inclined rotary helical conveyor having a lower article-receiving end and an upper articledischarging end, said conveyor having an outer cylindrical drum carrying in its interior a helical member for conveying articles through said drum, and means for maintaining in direct engagement with the exterior surface of said drum adjacent said upper article-discharging end thereof a cooling, condensing liquid for condensing any vapors within said drum to prevent discharge thereof through the article-discharging end of said drum.

110. In a degreaser, a housing having top and bottom walls and opposed inlet and outlet end walls each extending between said top and bottom walls, means for vaporizing a liquid, whose vapor is heavier than air, held in a lower portion of said housing, first condensing means for condensing the vapor at a predetermined level intermediate the top and bottom walls: of said housing, apertured cylindrical drum conveyor means rotatably mounted within said housing, said drum conveyor means being inclined upwardly toward said outlet end wall of said housing and having a lower inlet end portion adjacent said inlet end wall of said housing adapted to extend into liquid held in the lower portion of said housing and said apertured cylindrical drum conveyor means having an upper discharge end portion adjacent said outlet end wall of said housing terminating above the predetermined vapor condensing level, partition means extending across the interior of the housing intermediate the ends of said drum conveyor means and separating the interior of said housing into a vapor chamber and into a discharge chamber, said discharge end portion of said conveyor means being located in said discharge chamber, and said partition means including, at least in part, a double-walled portion having an interior space for receiving cooling liquid, means for rotating said drum conveyor means to obtain a direction of feed of articles therein from the lower inlet end portion to the upper discharge end portion of said conveyor means, means for directing articles from said inlet end wall of said housing into said lower inlet end portion of said drum conveyor means, means at said outlet end wall of said housing for receiving articles from said upper discharge end portion of said conveyor means, and second condensing means extending around the upper discharge end portion of said drum conveyor means for condensing vapors therein to prevent discharge of said vapors from said discharge end portion of said conveyor means.

11. A degreaser as recited in claim 6 and wherein said second condensing means includes a trough carried by and surrounding said discharge end portion of said conveyor means and adapted to contain a cooling liquid which directly engages said drum conveyor means at said discharge end portion thereof for condensing vapors therein.

References Cited by the Examiner UNITED STATES PATENTS 509,664 11/1893 Howard 202185.4 X 2,089,102 8/1937 Savage 202 2,090,191 8/1937 Edhofer 202-17() 2,273,939 2/1942 Dammers 202170 2,280,811 4/1942 Edhofer et al. 202-170 2,458,253 1/1949 Chisolm et al. 202194 X 2,662,851 12/1953 Jones et al. 202-470 2,673,835 3/1954 Kearney l34-l1 X 2,865,445 12/1958 Buchler 202238 X NORMAN YUDKOFF, Primary Examiner. GEORGE D. MITCHELL, Examiner.

Claims

1. A ROTARY DRUM DEGREASER COMPRISING A HOUSING HAVING TOP AND BOTTOM WALLS AND OPPOSED INLET AND OUTLET END WALLS EACH EXTENDING BETWEEN SAID TOP AND BOTTOM WALLS, MEANS FOR VAPORIZING A LIQUID, WHOSE VAPOR IS HEAVIER THAN AIR, HELD IN A LOWER PORTION OF SAID HOUSING, FIRST CONDENSING MEANS FOR CONDENSING THE VAPOR AT A PREDETERMINED LEVEL INTERMEDIATE THE TOP AND BOTTOM WALLS OF SAID HOUSING, APERTURED CYLINDRICAL DRUM CONVEYOR MEANS ROTATABLY MOUNTED WITHIN SAID HOUSING, SAID DRUM CONVEYOR MEANS BEING INCLINED UPWARDLY TOWARD SAID OUTLET END WALL OF SAID HOUSING AND HAVING A LOWER END PORTION ADJACENT INLET AND WALLS OF SAID HOUSING ADAPTED TO EXTEND INTO THE LIQUID HELD IN THE LOWER PORTION OF SAID HOUSING, AND AN UPPER DISCHARGE END PORTION ADJACENT SAID OUTLET END WALL OF SAID HOUSING TERMINATING ABOVE THE PREDETERMINED VAPOR CONDENSING LEVEL, MEANS FOR ROTATING SAID DRUM CONVEYOR MEANS TO OBTAIN A DIRECTION OF FEED OF SAID ARTICLES THEREIN FROM THE LOWER END PORTION TO THE UPPER DISCHARGE END PORTION THEREOF, MEANS EXTENDING BETWEEN SAID INLET END WALL OF SAID HOUSING AND SAID LOWER END PORTION OF SAID CONVEYOR MEANS FOR DIRECTING ARTICLES FROM SAID INLET END WALL OF SAID HOUSING TO SAID LOWER END PORTION OF SAID CONVEYOR MEANS, MEANS AT SAID OUTLET END WALL OF SAID HOUSING FOR RECEIVING ARTICLES FROM SAID DISCHARGE END PORTION OF SAID CONVEYOR MEANS, AND SECOND CONDENSING MEANS ABOUT THE UPPER DISCHARGE PORTION OF SAID DRUM CONVEYOR MEANS FOR CONDENSING THE VAPORS THEREIN AND THEREBY PREVENT DISCHARGE OF SAID VAPORS FROM THE UPPER PORTION OF SAIDD DRUM CONVEYOR MEANS.