Waste discharge valve for toilet bowl

[57] ABSTRACT

An improved waste discharge valve having a simplified mounting arrangement that generally facilitates final assembly to the flush bowl of a portable toilet. The preferred embodiment of the unique valve mounting arrangement simultaneously serves as a pivot axis about which the valve is freely movable. The preferred embodiment of the invention also utilizes a valve flap construction that is slightly dish-shaped so as to trap a small amount of flushing fluid and thereby form a water seal which prevents the passage of noxious odors from a holding tank located below the flush bowl.

Claims, 4 Drawing Figures

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PATENTED JAN H9/4

3.781.920

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3,781,920

WASTE DISCHARGE VALVE FOR TOILET BOWL

This invention is generally directed to portable waste handling systems such as are commonly used today in portable outhouse facilities and other portable toilets, such as for trailer and marine use. In particular, it relates to a unique type of discharge valve and mounting arrangement for a portable toilet flush bowl.

Today there is an increasing emphasis on avoiding the pollution of lakes and streams with discharged waste material. In some instances laws have been promulgated which require the provision of toilets for boats, camping trailers and the like, which are constructed to prevent the discharge of waste material from such vehicles. Since large numbers of portable toilet systems will be required in the near future, it is, as always, very important to minimize the per unit cost of materials and labor utilized in the construction of such systems.

Difficulties often arise in servicing these units since residue usually remains in the holding tank even after it is emptied. Further, the toilet facilities are usually mounted in cramped close quarters. Accordingly, simplified assembly and/or servicing procedures are very important considerations.

There have been numerous discharge valves used in combination with flush bowls to control the discharge of waste effluent therefrom. Typical (but not allinclusive) of these prior art valves are the ones illustrated in prior U. S. Pat. Nos. 139,531 and 2,401,098 issued to Barrett and to Peter, respectively. The trap valve arrangement disclosed in the Barrett patent is balanced by a counter-weight to cause a valve opening whenever the bowl is partially filled and an automatic valve closure when the bowl is emptied as a result of the opening process. The Peter patent discloses another valve structure that is counterbalanced to automatically close and which is also provided with a water seal to prevent the escape of noxious odors from a holding tank below.

However, both of these prior art devices, as well as others, suffer from several disadvantages that have, until now, presented undesirable problems. One of the difficulties involves the relatively high cost and labor involved in assembling the valve to the flush bowl. This is due primarily to the use of conventional hinges and screw fasteners in the prior art discharge valve arrangements. Further, due to the use of conventional, cumbersome mounting arrangements, the prior counterbalanced discharge valves are usually difficult to adapt for use in unusually cramped spaces. That is, the relative orientation of the counter weight position and valve opening direction with respect to the flush bowl is fixed with such conventional mounting arrangements. Such fixed relative positions may be acceptable for some specific applications, but unacceptable with other physical space limitations and configurations as should be appreciated.

Now, however, a greatly improved and unique mounting arrangement has been discovered for such discharge valves which significantly reduces the disadvantages discussed above.

The preferred exemplary embodiment of this invention comprises a formed plastic valve which is mounted by means of a hinge arrangement to a unique circular clip-shaped stainless steel rod. This clip slidably attaches to the formed rim of the usual toilet discharge port and includes an integral hinge. A cast lead weight is disposed at the outer end of the valve to counterbalance the weight of the plastic valve body. This arrangement allows the device to be clipped or mounted freely on the toilet bowl rim, while also allowing it to be adjusted to substantially any position within a full circle by simply rotating the mounted valve apparatus.

Preferably, this valve construction utilizes corrosion resistant materials so that it will operate continuously without attention or lubricants. No springs or mechaI nisms are employed for its operation as it simply works by the force of gravity.

Preferably, the plastic valve body is essentially flat with a very shallow dish form to it. In the closed position, the dish portion of the valve would fit flush against the bottom of the toilet bowl, and would trap or contain a small amount of the residual liquid left from the flushing action. Excess fluid would merely overflow the device and return to the holding tank.

Compared to conventional mounting arrangements, the simple clip and/or integral hinge rod of this invention represents a substantial savings in the cost of construction materials and labor.

The preferred embodiment discussed below not only completely cuts off any direct line of vision into the holding tank below, it also forms a liquid seal to help prevent the escape of noxious vapors from the holding tank. Further, this small amount of trapped liquid on the plastic valve surface serves to extinguish any lighted cigarettes dropped into the toilet and tends to minimize the adherence of solid waste to the plastic surface as might be the case if the surface were left in a dry condition.

Using the mounting arrangement of this invention, the discharge valve apparatus can be simply pushed directly onto the discharge part of the bowl, spreading the C-shaped clip sufficiently to pass the widest point in the discharge port diameter. Alternately, it is possible to mount the device by simply positioning one side of the C-clip correctly in the curled discharge port lip, then spreading the C-clip until it snaps over the opposite side of the curled lip. The second method is preferred as it is quicker, more stable during assembly, and requires less force. Ideally, the C-clip is exposed to less stress in this manner and, therefore, has better spring retention after mounting.

As should now be appreciated, the assembled discharge valve of this invention may be positioned in virtually an infinite number of positions about the bowl discharge port except for those arc areas where the extended counterbalance, etc. interfere with the particular configuration of holding tank, hoses, etc. being utilized for a particular application. This, of course, is a great advantage as it makes the toilet bowl readily adaptable to different toilet configurations. It also facilitates servicing as should be apparent to those in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects and advantages of this invention will be apparent from the followihg detailed description and the accompanying drawings, of which:

FIG. 1 is a fragmentary, somewhat schematic side view, partly in section, of an exemplary embodiment of a flush bowl having a discharge valve and attaching apparatus constructed according to this invention;

FIG. 2, is a view corresponding to FIG. 1 but showing another embodiment of the invention;

3,781,920

FIG. 3, is a view corresponding to FIG. 2 but showing the valve in an open position; and

FIG. 4 is a plan view of an exemplary embodiment of the mounting arrangement of this invention.

Referring now to FIG. 1, the usual flush toilet bowl 10 is adapted to mate with an upper opening in a holding tank (not shown). The lower end (discharge part) of the bowl, which usually is generally round in overall shape, is provided with the usual out-turned peripheral lip 12 defining a shallow outer peripheral groove 14. A flap-like discharge valve device 16 is mounted as a unit below the lower open end of the bowl by a clip 18, having a substantially C-shaped configuration.

As can best be seen in FIG. 4, the C-clip 18 consists of two relatively springy legs 20 integrally attached to a straight base portion 22 that also serves as an integral pivot pin for the discharge valve 16. Placed about this base portion 22, for free movement thereabout, is an elongated hinge bracket 24. One end of the bracket is provided with a V-shaped bearing section 26 that is adapted to freely embrace the base portion 22 of C-clip 18 thus permitting relatively free rotational movement therebetween.

Extending laterally from the bearing section 26 is a flange 28. The flange and a main body section 30 of the hinge bracket 24 are formed with apertures (not shown) that are adapted to receive nut and bolt fasteners 32 to secure the discharge valve to the bracket.

The main body section 30 of the hinge bracket has an angled lower end 34 that extends in a direction opposite to that of the flange 28. This lower end 34 has a counterweight 36, formed from any suitable material, e.g., lead, secured thereto. The counterweight is heavy enough to urge the discharge valve 16 upwardly against the lip 14 on the lower end of the bowl when the toilet ³⁵is empty and light enough to cause automatic valve opening when any desired predetermined amount of waste material and flushing fluid is deposited in the toilet as should be apparent to those in the art.

In the embodiment shown in FIG. 1, the discharge ⁴⁰valve itself is generally in the form of a trough having a downwardly and rearwardly sloping bottom terminating in an open rearward end 40. The trough can be made from any suitable material, e.g., styrene plastic. In the closed position shown in FIG. 1, the trough ⁴⁵blocks the line of sight through the bowl into the holding tank (not shown).

The forward end of the trough has an integrally formed outwardly projecting flange 42 terminating in a downwardly inclined lip 44 both of which extend partly around the adjacent sides of the trough, as at 45, to strengthen that portion of the discharge device attached to the hinge bracket. Both the flange and the lip have apertures therein (not shown) which are aligned ₅₅with the apertures in the hinge bracket 24 to receive ³the fasteners 32 and thereby secure the C-clip 18, the hinge bracket 24 and the trough 38 in one integral unit.

In an alternate preferred embodiment of the invention shown in FIGS. 2 and 3, the discharge device 10 ₆θ is shaped in the form of a shallow dish-like flap 46'having a generally flat bottom and urged by the counterweight 36 into abutting contact with the entire lower edge of the lip 14 on the bowl. In this position the bowl opening is completely closed, thereby blocking the line ₆₅of sight of the user into the holding tank. After a flushing operation, the waste matter is discharged into the holding.tank, and the flap 46, after it resumes the posi4 tion shown in FIG. 2, will capture a small quantity of flushing fluid in the shallow basin 48 of the flap. The liquid will rise to a level that is a fraction of an inch in height and thus form a water seal with the lip on the 5 bowl which serves to prevent the free escape of noxious fumes from the holding tank. However, if pressure in the holding tank increases due to the expansion of the gases therein (from ambient heating and the natural decomposition of the waste matter), the water seal will 10 allow such expanding vapors to bubble therethrough.

The novel C-clip 18 of the invention provides several advantages. In one respect the legs 20 of the C-clip make the mounting of the unit to the lower lip 14 of the bowl 12 much easier. The legs are relatively springy 15 and upon attachment to the bowl are spread apart from each other to conveniently facilitate mounting of the discharge valve over the open lower end of the bowl. The legs 20 are tightly held to the lip 14 by the compressive forces generated by the C-clip. This tight fit 20 will be sufficient to maintain the valve in operative position, notwithstanding severe shocks which may be imparted thereto during transport, etc. As should now be appreciated, the mounting arrangement may be made even more secure by deepening the groove around the discharge port.

Further, the base portion 22 of the C-clip is attached to the legs, and it also serves as a pivot for the entire valve. Thus, after the collection of waste effluent on the discharge valve and a subsequent flushing operation, ³⁰ the combined weight of the waste material and flushing fluid will overcome the opposing force of the counterweight 36 and move the discharge device downwardly (see FIG. 3) to dump the accumulated waste effluent into the holding tank. Upon cessation of the flushing operation, the counterweight will automatically reposition the discharge device into abutting engagement against the lower edge of the lip 14 on the bowl.

While only a few embodiments of this invention have been explicitly discussed, those in the art will recognize that many modifications may be made in these embodiments without in any way departing from the basic features of the invention as discussed above. Accordingly, all such modifications are considered as part of the invention.