Waste Disposal System And Method

Abstract

Vacuum and pressure are selectively applied by an air pump through a conduit interconnecting two tanks which have a second interconnecting conduit connectable to the access fitting of a boat waste receptacle. Application of vacuum withdraws the waste from the receptacle into one of the tanks and lake water into the second tank through a third conduit whose inlet end can be dropped overboard. The lake water is then expelled by air pressure into the receptacle as a flushing fluid and thence withdrawn into the first tank from which it and the previously withdrawn waste are finally expelled through a fourth conduit connectable to a public sewer or other disposal facility.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

My invention relates to the art of servicing, i.e., cleanout and flushing, of toilet waste receptacles, of small pleasure boats, airplanes, travel trailers and like vehicles. Increasing anti-pollution legislation imposes severe problems on the operators of such craft. For example, certain states now prohibit the indiscriminate dumping of such receptacles into the adjacent waterways, even at considerable distances off shore. This makes it necessary for operators of such craft to make suitable provision for discharging their receptacles into a public sewer system or other land based disposal facility approved by the authorities. My invention provides an improved system and method for accomplishing this desired result which both is entirely sanitary and takes but a relatively few minutes to accomplish. A principal feature of my invention distinguishing it from the prior art is that provision is made for first withdrawing the waste from the receptacle being serviced, followed by flushing the receptacle and withdrawing the flushing fluid therefrom, followed, if desired, by refilling the receptacle with a second quantity of flushing fluid, and thence finally expelling the withdrawn waste and initial flushing fluid into a public sewer. The system also distinguishes importantly from the prior art in that the pump means is completely isolated from the waste and flushing fluid flow circuit so that all problems of clogging the pump are avoided.

2. Description of the prior art

The closest approach to such a system in the prior art of which I am aware is that disclosed in the U.S. Pat. No. 3,528,462 to Quase wherein waste from the boat access fitting is withdrawn through a pump to a submerged storage tank, from which it may be periodically discharged through suitable piping to an installation on shore for later further removal by a tank truck or the like. No provision, however, is made for flushing and refilling the waste receptacle in the boat, and all waste withdrawn therefrom must pass through the pumps. In the U.S. Pat. No. 3,546,713 to Gagne an on-board waste disposal system for boats is disclosed in which the waste is pumped into successive tanks for maceration, sterilization and liquid separation, respectively, from the last of which the liquid is discharged over board below the water line. No provision is made for removal of the solid wastes, and, as in the Quase patent, all waste flow is directly through the various pumps used in the circuit.

SUMMARY OF THE INVENTION

It is therefore a principal object of my invention to provide for servicing such vehicle equipped waste receptacles by selectively applying vacuum or air pressure to a waste holding tank and a flushing fluid holding tank in order to draw the waste into the former and flushing fluid into the latter so that the flushing fluid may thence be delivered to the receptacle and thereafter withdrawn into the waste holding tank for final expulsion therefrom along with the previously withdrawn waste into a public sewer or other external disposal facility. It is a further important object of my invention to provide such a system wherein the pumping of waste and flushing fluid from the receptacle being serviced is accomplished without allowing these materials to pass through the pump, thereby avoiding any possibility of the pump becoming clogged or worn by passage of those materials therethrough.

In accordance with the invention, the waste receptacle may be refilled with clean flushing fluid by withdrawing a second quantity thereof into the flushing fluid holding tank and thence discharging the same into the receptacle after the initial flushing fluid quantity therein has been withdrawn into the waste holding tank.

The means by which these and other objects and advantage of the invention are attained will be more clearly understood from the following detailed description of one preferred embodiment selected for illustration, having reference to the drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic layout of a waste receptacle servicing system embodying the invention;

FIG. 2 is a cross sectional view of a check valve used in the system of FIG. 1;

FIG. 3 is an elevational view of a physical unit incorporating the features of the system shown in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now in detail to the draiwngs, and first to FIG. 1, a system is shown including a closed waste holding tank 1, a closed flushing fluid holding tank 2, a coupler 3 connectable to a typical waste access fitting (not shown) of the boat or other vehicle whose waste receptacle is to be serviced, an air pump 4 and suitable connecting conduits for carrying out the invention.

The waste holding tank 1 has an outlet, preferably located in the lower portion thereof, in the form of a conduit 5 through which flow is limited to the outward direction only by a check valve 6. The conduit 5, downstream of the check valve 6, may be connected by a flexible hose (not shown) to a public sewer or other suitable waste disposal facility. In the upper portion of the tank 1 is a combined dual inlet and outlet shown in the form of a conduit 7 which connects with the interior of the tank via a valve seat 8. A fluid level responsive valve 9 is provided for closing the outlet conduit 7 against outward flow by moving into abutment with the seat 8 when the fluid level in the tank reaches a predetermined height. The tank 1 is also provided with an inlet, preferably but not necessarily located in the upper portion thereof, as shown in the form of a conduit 10 through which flow is limited to the direction inwardly of the tank by a check valve 11. The conduit 10 serves as a waste conduit, being connected at its opposite end to the coupler 3. The conduit 7 is an air conduit having a branch 7' whose opposite end forms a combined inlet and outlet in the upper portion of the flushing fluid holding tank 2. As in the case of the tank 1, the latter combined inlet and outlet is provided with a valve seat 12 which is closable against flow therethrough by a fluid level valve 13. The tank 2 also has an inlet, shown in the form of a conduit 14, through which flow is limited to the direction inwardly of the tank by a check valve 15. To this conduit 14, upstream thereof from the check valve 15, may be connected a flexible hose (not shown) leading to a suitable source of flushing fluid. In the case of servicing a waste receptacle of a boat while docked this is simply accomplished by extending the opposite end of the flexible hose overboard below the water line. Obviously, however, the end of the conduit 14 upstream of the check valve 15 might be similarly connected to any suitable water reservoir or pressure water supply line. The flushing fluid holding tank 2 is also provided with a combined inlet and outlet in the form of a conduit 16 which connects thereto at a height preferably located below that of the valve seat 12 and valve 13. This conduit 16, which serves as a flushing fluid delivery conduit, connects at its lower end with the coupler 3 in common with the waste conduit 10.

A second branch 7" of the air conduit 7 is shown leading to a four-way or selector valve 17. The air conduit branch 7" forms a combined inlet and outlet of the selector valve 17 which interconnects, through a vacuum air line 18 and a pressure air line 19 with the inlet and outlet, respectively, of the air pump 4. It will be understood that the pump 4 is suitably driven, as by an electric motor (not shown). A suitable adjustable relief valve 20 is shown installed in the vacuum air line 18 to limit the vacuum applied therein by the pump 4 to a predetermined value, such as 15 inches of mercury. Also a suitable pressure relief valve 21 is shown installed in the air pressure line 19 to limit the pressure developed therein to a predetermined value, such as 20 pounds per square inch. 22 and 23 are gauges to indicate the respective vacuum and pressure, respectively, developed by the pump 4 in operation. A filter 24 may also be incorporated in the vacuum air line 18 to intercept moisture and any foreign particles which might otherwise be drawn into the pump 4.

Selectively closable and openable valves 25 and 26 are shown installed in the air conduit 7 and flushing fluid conduit 16, respectively. The inclusion of the valve 25 is not essential to the operation of the system, but it does perform the useful function of expediting the applications of vacuum and pressure to the flushing fluid holding tank 2 during withdrawal of fluid therein through the conduit 14, and expulsion of such fluid into the receptacle via the coupler 3, respectively, since closure of the valve 25 during those times renders it unnecessary to build up the same vacuum or pressure in the waste holding tank 1. Also, while the selector valve 17 and the valves 25 and 26 may be operated manually, it will be appreciated that suitable energizing means (not shown) such as solenoids may be incorporated therewith in a circuit including timing or sensing devices and a start button, so the different sequential operations of the system may be carried out automatically.

THe sequence of operating steps in servicing a waste receptacle will now be described. The air pump 4 preferably operates continuously throughout the cycle, and upon setting the selector valve 17 in the dotted line position shown and opening the valve 25 and closing the valve 26 vacuum will then be applied both to the waste holding tank 1 and the flushing fluid holding tank 2. This will result in withdrawing the waste contained in the receptacle being serviced into the tank 1 and simultaneously withdrawing flushing fluid through the conduit 14 into the tank 2. Since such waste receptacles are normally vented, this action may be continued until an audible loss of vacuum is noted in the waste conduit 10. It will be appreciated that the capacity of the waste holding tank 1 should be large enough to accomodate the contents of the largest receptacle intended to be serviced, plus the fluid holding capacity of the flushing fluid holding tank 1. Over-filling of the flushing fluid holding tank is prevented by closure of the fluid level responsive valve 13 therein. Next, upon resetting the selector valve 17 to the solid line position shown, closing valve 25 and opening the valve 26 air pressure will thence be applied by the pump 4 to the tank 2 for expelling the flushing fluid therefrom, into the receptacle via the coupler 3. When this is completed, the selector valve 17 is reset in its dotted line position, the valve 25 is again opened and the valve 26 is again closed, whereupon vacuum is again applied by the pump to the tanks 1 and 2 resulting in the flushing fluid being withdrawn from the waste receptacle through the coupler 3 into tank 1 while simultaneously a fresh quantity of flushing fluid is drawn into the tank 2 through the conduit 14. Thereafter, if it is desired to refill the waste receptacle with a fresh quantity of flushing fluid, which is usually the case, the selector valve 17 is moved to its solid line position, the valve 25 is closed and the valve 26 is opened, thereby resulting in air pressure being applied to the contents of the tank 2 to force the fresh flushing fluid through the coupler 3 into the waste receptacle. Thereafter, or if such refilling of the receptacle is deemed unnecessary, the valve 25 may be opened and the valve 26 closed with the selector valve 17 in its solid line position so that pressure is applied by the pump through conduit 7 to the waste holding tank 1 to expel to the sewer via the conduit 5 all of the waste and flushing fluid previously withdrawn thereinto from the receptacle. It will be appreciated that the check valve 11 in the waste conduit 16 prevents return of waste therethrough during this discharge of material from the tank 1, and that likewise the check valve 15 prevents return flow of flushing fluid through the conduit 14 when discharging such fluid from the tank 2 to the receptacle, and that check valve 6 prevents loss of vacuum in the waste holding tank 1 during withdrawal thereinto of waste from the receptacle via the coupler 3 and waste conduit 10.

Referring to FIG. 2 it will be seen that the check valve 11 in the waste conduit leading to the tank 1 preferably comprises an elongated housing 27 which may be constructed in one piece, or in a plurality of sections as shown. In the particular embodiment illustrated the body of the housing is formed of a pair of oppositely facing bell shaped members 28 and 29 whose large ends are joined together by a cylindrical member 30. The inlet to the housing is formed by a nipple 31 having an inner portion 32 extending into and sealingly joined to the smaller end of the bell member 28, and an outer portion 33 which may be serrated or threaded as at 34 for gripping engagement with the adjacent end of the waste conduit 16 (FIG. 1). Likewise, the outlet end of the housing is similarly formed by a nipple 31' for connecting the smaller end of the bell member 29 to its connecting end of the waste conduit 16. Sealingly received within the inner portion 32 of the nipple 31 and extending therefrom into the housing is a rigid sleeve member 35 connecting a further extending sleevelike member 36 of elastically flexible material. The opposite sidewalls 37, 38 of this flexible member 36 are preformed so as to normally taper toward and into abutment with each other (as shown in their solid line positions) to form a closure against reverse flow through the housing. During forward flow, fluid pressure forces the extended ends of the oposing sidewalls 37, 38 out of engagement with each other and toward their positions shown in dotted lines. Preferably a valve of this construction is also used for the check valve 6 in the discharge conduit 5 from the waste holding tank 1. Valves of this construction have proven exceptionally reliable and positive in operation and have a further advantage of requiring relatively low fluid pressures to effect forward flow therethrough, yet afford a positive seal against reverse flow.

FIG. 3 shows a portable unit incorporating the waste holding tank 1, flushing fluid holding tank 2, air pump 4, valving and interconnecting conduits and flow lines described in connection with FIGS. 1 and 2. The assemblage, as shown, is mounted on a trailer-like chassis 40 having road wheels 41 for conveniently maneuvering the unit around a marina dock, air field or travel trailer servicing area.

It is appreciated that the individual components of the system may take various different forms and that their interconnections may be modified from those specifically illustrated and described without departing from the spirit and scope of my invention as hereinafter claimed.

Claims

Having thus described my invention, I claim:

1. In a system for servicing waste receptacles of marine and other vehicle-equipped sanitary facilities, a coupler connectable to the waste receptacle to be serviced, a waste holding tank having an outlet connectable to an external sewer, a flushing fluid holding tank having an inlet connectable to a source of flushing fluid, a waste conduit interconnecting said coupler and waste holding tank, a flushing fluid conduit interconnecting said coupler and flushing fluid holding tank, and means for selectively applying vacuum and air pressure to the interiors of each of said tanks for sequentially effecting the withdrawal of waste into the waste holding tank from the receptacle, delivering a quantity of flushing fluid to the receptacle, withdrawal of the flushing fluid quantity into the waste holding tank and expulsion of said waste and flushing fluid quantity from the waste holding tank to said sewer, said means including an air pump having an inlet and outlet, an air conduit having connections with each of said tanks, a valve selectively operable to connect the air conduit to either of said pump inlet or pump outlet, and valves respectively operable to control air flow to and from said waste holding tank via said air conduit and flow of flushing fluid to and from said flushing fluid holding tank via said flushing fluid conduit, said air conduit connections with the tanks being located in the upper portions of the tanks and each including a valve seat and a fluid level responsive valve movable against the seat to block flow outwardly of the tank when the fluid level therein reaches a predetermined height, said means further including check valves in each of said waste holding tank outlet, flushing fluid tank inlet, and waste conduit, at least one of said check valves in the waste holding tank outlet and waste conduit comprising an elongated valve housing having an inlet at one end and an outlet at the other end, a fixed sleeve extending into the housing from said inlet, and an elongated hollow member sealingly secured at one end to the sleeve and having elastically yieldable sidewall portions extending toward said outlet and tapering toward each other to form a closure therebetween at their extended ends.

2. In a system for servicing waste receptacles of marine and other vehicle-equipped sanitary facilities, a coupler connectable to the waste receptacle to be serviced, a closed waste holding tank having a check valve controlled outlet in the lower portion thereof, a closed flushing fluid holding tank having a check valve controlled inlet connectable to a source of flushing fluid, an air pump having an inlet and an outlet, an air conduit interconnecting the upper portions of said tanks, a selector valve alternatively operable to connect either said pump inlet or pump outlet to said air conduit, a selectively closable and openable valve controlling flow in said air conduit between said selector valve and the waste holding tank, a waste conduit interconnecting said coupler and the lower portion of the waste holding tank, a flushing fluid conduit interconnecting said waste conduit and the lower portion of the flushing fluid holding tank, a selectively openable and closable valve controlling flow in said flushing fluid conduit, and a check valve accommodating one way flow only to the waste holding tank from said waste conduit, said last named check valve including a valve housing having an inlet connected to said waste conduit and an outlet connected to said waste holding tank and a sleevelike member of elastically flexible material within said housing, said member having one of its ends connected to said housing inlet and its opposite end extending toward said housing outlet, said extended end of said member having a normally pinched configuration in which the opposite sidewalls thereof are in abutting engagement with each other to form a closure against reverse flow.