Stainless steel toilet resistant to corrosion by sea water

Abstract
A stainless steel toilet resistant to corrosion by sea water. The toilet has a toilet bowl portion which is butt-welded to a rim. The welding is carried out while the inside surface of the weld line is flushed with argon gas. Similarly, a P-trap is butt-welded to an exit opening at the bottom of the bowl portion. A flush ring assembly is supported below the rim member. The result is a toilet which can be operated with sea water without corrosion for a period of years.
Description




BACKGROUND OF THE INVENTION




The field of the invention is plumbing fixtures and the invention relates more particularly to toilets and still more particularly, to toilets useful when sea water is used in place of fresh water to flush the toilet.




Stainless steel toilets have been used for many years and are particularly adaptable for use in prisons. An example of a stainless steel toilet is shown in U.S. Pat. No. 5,067,181.




Attempts to use stainless steel toilets utilizing sea water as the flushing medium have in the past been unsuccessful. In spite of the development and use of more corrosion resistant stainless steel, sea water still brought about corrosion at the weld lines and all known efforts to produce a corrosion-free toilet for use with sea water to date have fallen short.




BRIEF SUMMARY OF THE INVENTION




It is an object of the present invention to provide a stainless steel toilet which can operate utilizing sea water as the flushing medium without exhibiting significant corrosion.




The present invention is for a stainless steel toilet resistant to sea water. The toilet comprises a toilet bowl portion having an oval upper ring, sidewalls extending downwardly from the upper ring to a trap outlet ring. A rim member has an oval lower ring of the same size and shape as the oval upper ring of the toilet bowl. The rim member extends upwardly and then inwardly to a seat rest portion, which in turn, extends inwardly and downwardly to an inner terminus edge. The rim member is fabricated from stainless steel and the upper ring of the toilet bowl portion is butt-welded to the oval lower ring of the rim member along a butt-weld line. A P-trap, having an upper ring having the same size and shape as the trap outlet ring of the toilet bowl portion, is fabricated from stainless steel and butt-welded to the trap outlet ring along a butt-weld ring. A flush ring assembly is supported below the rim member and covered by the rim member. The flush ring assembly is fabricated from a small conduit provided with a plurality of water outlet passageways aimed to direct a plurality of water flushing streams against the inner surface of the toilet bowl portion.




The butt-welding is carried out with an argon gas flow maintained on an inner surface of a weld line during the welding step. A process for fabricating the stainless steel toilet is also set forth.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a side view of the stainless steel toilet of the present invention.





FIG. 2

is a top view thereof.





FIG. 3

is a back view thereof.





FIG. 4

is an enlarged cross-sectional view taken along line


4





4


of FIG.


2


.





FIG. 5

is an exploded side view showing the rim, bowl, and upper portion of P-trap of the toilet of FIG.


1


.





FIG. 6

is a perspective view of the exterior of the bowl and rim of the toilet of FIG.


1


.





FIG. 7

is a view of an argon purging assembly ring assembly used during the butt-welding process of the rim to the bowl.





FIG. 8

is a side view showing the argon purging assembly for welding the trap outlet ring to the P-trap.





FIG. 9

is a bottom view of the flush rim of the toilet of FIG.


1


.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




The stainless steel toilet of the present invention is shown in side view in FIG.


1


and indicated generally by reference character


10


. The toilet has a toilet bowl portion


11


which is welded to a rim member


12


at its top and to a P-trap


13


at its bottom. These three elements are shown separated in

FIG. 5

of the drawings. The bowl is supported by toilet housing


14


, which is preferably also fabricated from stainless steel, although it is not normally contacted by sea water. Other methods of supporting the toilet assembly may be substituted for housing


14


, depending upon the environment in which the toilet is used.




The P-trap


13


curves-upwardly and then downwardly to an outlet


15


. During flushing, sea water enters through elbows


16


, then passes through flush inlet tube


17


. Flush inlet tube


17


terminates in flushing rim junction box


18


, which has two outlets. The larger outlet


19


feeds blowout tube


20


. Blowout tube


20


passes sea water into a blowout jet casting


21


, which feeds sea water into the interior of P-trap


13


along the upwardly sloped top edge


22


thereof. The top edge of blowout tube


20


is indicated by reference character


24


and the bottom edge by reference character


23


.




The smaller outlet


25


feeds flush ring


26


. Flush ring


26


is shown in

FIG. 9

of the drawings and has an inlet


27


, which feeds sea water into tee


28


. Tee


28


has two outlets


29


and


30


, which feed a continuous hollow polymeric loop


31


. Loop


31


has a plurality of holes


32


which direct water against the inside surface of toilet bowl portion


11


. As shown in

FIG. 4

, the holes


32


are formed so that the sea water is directed at an angle “a” from the vertical. An angle of about 35° provides an appropriate spray pattern for rinsing the inner surface


33


of toilet bowl


11


.




Flush ring


26


is preferably held under the upper surface


34


of rim member


12


by a plurality of blocks


35


. Blocks


35


are adhered by an adhesive to the under surface


36


of the upper surface


34


of rim member


12


. It has been found that a block fabricated from ABS polymer is satisfactory for this purpose. As seen in

FIG. 4

, the upper edge of flush ring


26


is about even with the lower inner terminus


37


of rim member


12


. The toilet of

FIG. 1

should be fabricated from a highly corrosion resistant stainless steel such as 300 series austenetic stainless steel.




It was found by numerous experiments that conventional welding techniques used for stainless steel toilets did not prevent corrosion, even when 300 series austenetic stainless steel was used. The corrosion by sea water is especially harmful to the weld lines of the finished toilet. Conventionally, stainless steel toilets are made with an overlap so that the various parts can be easily assembled prior to the welding. Such overlaps, however, resulted in crevice corrosion and it was found that by utilizing butt-welding, crevices are eliminated and a corrosion-free assembly could result. It was also found important to bathe the interior of the weld line with argon, which sanitizes the atmosphere behind the weld and allows for better weld penetration with less heat allowing for less potential of the forming of chromium carbides ergo less potential for corrosion.




The welding technique to accomplish a weld which will not corrode under the frequent impingement of sea water is illustrated in

FIGS. 6 and 7

of the drawings. In

FIG. 6

, the toilet bowl portion


11


and the rim member


12


are placed on a table


40


and a series of clamps


41


are adjusted so that their inner faces


42


abut the oval upper ring


43


of toilet bowl portion


11


. They also abut the oval lower portion


44


of rim member


12


. Sufficient clamps are used so that the two members are aligned in a lower edge to upper edge alignment. It has been found that about 10 clamps are sufficient for this purpose. After the two parts are clamped as shown in

FIG. 6

, they are tack welded so that they will retain the proper alignment during the final welding process.




Next, the tack welded assembly


54


is inverted to an upright position as shown in FIG.


7


and placed over an argon supply post


44


. A pair of argon supply rings


45


and


46


are placed inside the toilet bowl portion


11


through the opening in rim member


12


. A series of flexible feed lines


46


are affixed to the argon supply rings and are fed by a manifold


48


. Manifold


48


is fed from a source of argon through flexible tubes


49


and


50


to fittings within argon supply posts


44


. Next, a gasket


51


and a cover


52


are placed over the opening in rim member


12


. A series of clips


53


hold the argon supply rings


45


and


46


adjacent the weld line


55


. Next, the interior of the assembly of

FIG. 7

is filled with argon and the argon passes outwardly from argon supply rings


45


and


46


through outwardly facing holes so that the inner surface of weld line


55


is bathed in argon. Next, the bowl


11


and rim


12


are carefully welded. Cover


52


has a small hole through its flat upper plate so that air can escape as the argon is filling the interior of the bowl.




After completing the upper weld, the P-trap is similarly butt-welded as indicated in

FIG. 8

of the drawings. In this case, the cover


52


is removed as is the argon supply assembly and the bowl is again inverted and placed on a rubber flange


57


which surrounds an argon supply plate


58


. Supply plate


58


is somewhat like a showerhead having a plurality of holes through which argon passes, filling the space above rubber flange


57


with argon gas. P-trap


13


has a circular end ring


59


which matches the circular exit opening


60


of toilet bowl portion


11


. The bowl


11


and P-trap


13


are clamped so that the end ring


59


abuts the circular exit opening


60


. After the interior surface is filled with argon, the two end rings are carefully welded together to form a butt-weld ring.




It is also important that the top edge


24


of blowout tube


20


is butt-welded to the flushing rim junction box


18


. Similarly, it is important that blowout tube


20


have its bottom edge


23


butt-welded to blowout jet casting


21


.




By taking these precautions, the net result is a toilet assembly having welds with no crevices which can withstand the use of sea water over long periods of time without corrosion. The result is a relatively lightweight, as compared to porcelain, toilet assembly. Unlike porcelain to which metal fittings are attached and rust, discoloring the porcelain, the stainless steel remains uncorroded and retains its original appearance.




The present embodiments of this invention are thus to be considered in all respects as illustrative and not restrictive; the scope of the invention being indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.



Claims
  • 1. A stainless steel toilet resistant to corrosion by sea water, said toilet comprising:a toilet bowl portion having an oval upper ring, side walls extending downwardly from said oval upper ring to a trap outlet ring, said toilet bowl portion being fabricated from stainless steel sheet metal, a rim and seat member having an oval lower ring of the same size and shape as the oval upper ring of said toilet bowl portion and said rim and seat member extending upwardly and then inwardly to a seat portion which, in turn, extends inwardly and downwardly to an inner terminus edge and said rim and seat member being fabricated from stainless steel and said oval upper ring of said toilet bowl portion being butt welded by butt welding to said oval lower ring of said rim and seat member along a butt weld line and wherein said butt welding is carried out by supporting at least one argon supply ring held adjacent an inner surface of said butt weld line, said at least one argon supply ring having outwardly facing openings through which argon escapes and bathes the inner surface of said butt weld line with argon; a P-trap having an upper ring having the same size and shape as the trap outlet ring of said toilet bowl portion and said P-trap being fabricated from stainless steel and said upper ring of said P-trap being butt welded to said trap outlet ring along a butt weld ring and wherein said butt welding is carried out with argon gas maintained on an inner surface of a weld line during a welding step; and a flush ring assembly supported below said rim and seat member and covered by said ring and seat member, said flush rim assembly being fabricated from a hollow conduit supported independently of said rim and seat member provided with a plurality of water outlet passageways aimed to direct a plurality of water flushing streams against an inner surface of said toilet bowl portion and said flush ring assembly having a sea water inlet opening.
  • 2. The stainless steel toilet of claim 1 wherein said stainless steel is 300 series austenitic stainless steel.
  • 3. The stainless steel toilet of claim 1 wherein said flush ring assembly is supported below said rim and seat member by a plurality of polymeric blocks adhered to an underside of said rim and seat member and to said flush ring assembly.
  • 4. The stainless steel toilet of claim 3 wherein said plurality of water outlet passageways are formed to direct streams of water downwardly at about 35 degrees from the vertical toward an inner surface of said toilet bowl portion.
  • 5. The stainless steel toilet of claim 1 further including a stainless steel flushing rim junction box having a flush ring sea water outlet connected to said flush ring assembly and said flushing ring junction having a sea water opening inlet butt welded to a stainless steel sea water inlet tube and said flushing ring junction having a blowout tube outlet butt welded to the inlet of a blowout tube and said blowout having an outlet butt welded to a blowout jet casting and said blowout jet casting having an outlet welded to an upper side of said P-trap.
  • 6. A process for fabricating a stainless steel toilet impervious to corrosion by sea water comprising:forming a toilet bowl portion having an oval upper ring, side walls extending downwardly from said oval upper ring to a trap outlet ring, said toilet bowl portion being fabricated from 316 stainless steel; forming a rim and seat member having an oval lower ring of the same size and shape as the oval upper ring of said toilet bowl portion and said rim and seat member extending upwardly and then inwardly to a seat portion which, in turn, extends inwardly and downwardly to an inner terminus and said rim and seat member being fabricated from 316 stainless steel; butt welding said oval upper ring of said toilet bowl portion to said oval lower ring of said rim and seat member while maintaining an inner surface of a resulting weld line immersed in argon during said butt welding step and wherein said butt welding is carried out by supporting at least one argon supply ring held adjacent an inner surface of said butt weld line, said at least one argon supply ring having outwardly facing openings through which argon escapes and bathes the inner surface of said butt weld line with argon; forming a P-trap having an upper ring having the same size and shape as the trap outlet ring of said toilet bowl portion and said P-trap being fabricated from 316 stainless steel; and butt welding said upper ring of said P-trap to said trap outlet ring of said toilet bowl portion while maintaining an inner surface of a resulting weld line immersed in argon during said butt welding step.
  • 7. The process of claim 6 further including the step of affixing a flush ring to the under-surface of said ring and seat member, said flush rim being fabricated from a polymer.
  • 8. The process of claim 6 further including the step of forming a flushing ring junction box having a sea water inlet, a toilet bowl and rim and seat member outlet, a flush ring feed opening and a blowout tube outlet and butt welding said sea water inlet to an outlet of a flush inlet tube, butt welding said toilet bowl and rim and seat member outlet to said toilet bowl and rim and seat member and forming a blowout tube having a blowout tube inlet and a blowout tube outlet and butt welding said blowout tube inlet to said blowout tube outlet of said flushing ring junction box, forming a blowout jet casting having a blowout tube inlet and a P-trap inlet portion and butt welding said blowout tube outlet of said blowout tube to said blowout jet casting blowout tube inlet and butt welding said blowout jet casting P-trap inlet portion to an opening in said P-trap and connecting said flush ring feed opening to an inlet of said flush ring.
US Referenced Citations (5)
Number Name Date Kind
4454405 Riley Jun 1984 A
4538307 Barnum et al. Sep 1985 A
4559650 Prukner Dec 1985 A
5067181 Hafner et al. Nov 1991 A
5142707 Prue Sep 1992 A