Dual Flush Toilet Mechanism

The invention relates to a toilet flush tank mechanism, and, more particularly, to a selectively bouyant float securable to the flush tank outlet valve adapted for permitting a dual flush system.

Conventional flush-tank toilets in homes and apartments are designed to use a standard volume of water which is considered necessary to flush the toilet bowl satisfactorily under maximum requirement conditions. Often less than maximum water volume can satisfactorily flush the toilet. Accordingly, one way to save water which is so wastefully flushed through toilets is to provide a selective flushing system which utilizes a full flush cycle for solid wastes and a partial flush for liquid wastes.

It may also be seen that in circumstances wherein a shortage of water exists or where it is necessary to use a minimum of water during flushing of a toilet, such as in droughts or when the toilet is connected to a cesspool system of sewerage, it is advantageous to provide dual flushing systems. Apparatus therein designed to provide dual flushing systems for flush-tank toilets may include multiple outlet ports, devices actuated by the fall of a separate float which exerts a force on the outlet valve, or devices actuated by the fall of the conventional float which controlls the inlet means and which by falling exerts a force on the outlet valve.

There are numerous disadvantages to these prior art devices. Some of the aforesaid mechanisms require more than one exterior flushing handle, others have multiple levers, still others employ cams and locking devices. Many of such mechanisms are unreliable in every day operations. Moreoever most of the aforesaid designs are costly and require considerable work, skill and tools for installation. It has also been found that such devices are often hard to operate due to poor leverage characteristics of the actuating mechanism thereof and multiple exterior actuating handle arrangements. Also such devices often include parts which are arranged in a manner wherein lateral forces are exerted on cooperating parts thereof in a manner to cause poor seating of the float means for stopping the flow of water at the termination of flushing cycle or binding of the actuating lever during movement thereof. A further problem has been the wear factor between moving parts which results in poor operation and readjustment of the relative positions of the cooperating parts of the flush tank.

It would be an advantage therefore to provide an improved dual-flush mechanism which fits any ordinary flush-tank toilet and overcomes the problems of the prior art. The apparatus of the present invention is designed for just such a purpose and includes a single open ended float housing directly securable to a commode flush valve and having selectively regulatable venting ports for controlling float weight and bouyancy by the water-air ratio therein. In this manner, additional levers and/or latches and other flush tank apparatus is not necessary to effect a dual-flush system. Similarly, the effective cost of such a device is drastically lowered as is the complexity of installation.

The invention relates to apparatus for selectively discharging substantially all or only a predetermined portion of the water within the flush tank of a toilet and includes a float housing having selectively regulatable venting ports. More particularly, one aspect of the invention includes an improved dual flush control device of the type coupled to the flush valve of commode tanks having a drain valve seat, a drain pipe connected to the seat, a float-type flexible valve, a secondary float connected to the valve so as to effectively ride on the flexible valve and sink it prior to the surface of the liquid in the flush tank reaching the top of the flexible valve. The improved device is comprised of an open ended float having a vented upper surface and trapped air space formed therein. The float is slidably connected to the flexible valve and constructed to selectively resist rapid changes of water level therein so as to allow its weight to ride upon the flexible valve to sink it prior to a complete flush.

In another aspect of the invention, the improved float is comprised of an inverted cupped shaped housing having a central tubular element for receiving the shaft of the flexible valve therethrough. The cup is vented at the top surface thereof with a tubular port which entraps air upwardly thereof. The entrapped air permits the float to rise to the surface of the tank between flushes. If the cup is held in the upward position during the flushing action by the tank lever, the commode tank water level drops below it and the cup water is permitted to escape. In this manner a normal flush is permitted.

In yet another aspect, the invention includes an inverted cup float having a tubular venting port of sufficient size for communicating with the atmosphere in such a manner as to permit the water level inside the float to equalize with that of the commode tank during a flush. In this manner the bouyancy of the cup is maintained during flushes to again permit complete commode tank draining.

For a more complete understanding of the present invention, and, for further objects and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of one embodiment of apparatus constructed in accordance with the principles of the present invention disposed within the flush tank of a conventional commode with portions thereof cut away to illustrate the operation thereof;

FIG. 2 is an enlarged side elevational, cross-sectional view of the float housing shown in FIG. 1 taken along lines 2--2 thereof; and

FIGS. 3, 4 and 5 are fragmentary side elevational views of the apparatus of FIG. 1 illustrating in a three step sequence, the functioning of the present invention through one mode of operation.

Referring first to FIG. 1, there is shown in fragmentary perspective a commode tank 10 of conventional design, wherein means are provided for selectively providing dual volume flush modes. The tank 10 as shown, includes an upwardly opening tank member 12 and a removable cover 14. The bottom of the tank is referred to by the reference number 16 and has an outlet opening 17 formed therethrough. The upper end of an outlet pipe 18 is secured through the outlet opening 17 and said pipe includes a valve seat 20 at its upper terminal end. Formed integrally with the upper end of the outlet pipe 18 is an overflow standpipe 22 and the upper end of the standpipe 22 projects to an elevation spaced above the upper water level 24. The elements of the intake valve, such as the lever arm float, being conventional, are not shown.

The front wall 28 of the tank member 12 has an opening (now shown) formed therethrough and a shaft portion (not shown) having a lever-type handle 30 on its outer end. An operating arm 34 is secured to the shaft of the handle 30 and extends across the upper area of the tank 10, generally parallel to the front wall 28. A second arm 36 generally interconnects arm 34 with a flush valve 38 in conventional commodes. Flush valve 38 in this particular embodiment is comprised of a flexible bulb 40 usually formed of rubber, or the like, which seats across the valve seat 20 and is removable therefrom via valve stem 42. The valve stem 42 is secured to the top of flush valve 40 with a threaded interconnection 44 and is supported thereabove through a support bracket 46 extending outward from overflow pipe 22. The conventional commode tank 10 is generally provided in such a configuration wherein actuation of the handle 30 lifts the lever arms 34 and 36 respectively to pull upwardly valve stem 42 and valve bulb 40 to permit flow of the water therein through drain pipe 18. The bulb 40 generally encapsulates air therewithin providing bouyancy and permitting the commode tank 10 to complete the flush before the weight of the valve 38 causes it to seat and seal the tank for refilling.

In accordance with the principles of the present invention apparatus is provided for securement to the flush valve 38 and includes a float housing 50 formed of plastic, or the like, slidably mounted upon the valve stem 42. A movable stop 52 is provided beneath the housing 50 and upon the stem 42 for permitting selectivity of float movement and variations in flush mode characteristics. Referring now to FIG. 2, there is shown a cross-sectional elevation of the housing 50 wherein it may be seen that a central tubular element 54 is provided therein and sealably secured through the upper surface 56 thereof. The tube 54 is adapted for receiving the valve stem 42 therethrough for centralized, slidable engagement therewith. The housing 50 is further comprised of generally cylindrical side walls 58, sealably depending from the upper surface 56 for encapsulating a selected volume of air and water therein.

Still referring to FIG. 2, it may be seen that the housing 50 is provided with a vented, or ported upper surface 56. In the particular embodiment of housing 50 shown in FIGS. 1 and 2 a pair of tubular ports are provided. A first port 60 is formed with a small aperture or orifice 62 formed in the bottom surface 64 thereof. A second port 66 is also provided on the surface 56 with a larger aperture 68 provided along the lower recesses thereof. A stopper, or sealing element 70 is shown to be received within the port 66 for sealing same against fluid flow during operation within the commode tank 10. The stopper 70 may be seen to be preferably of a size adaptable for insertion in either of the ports 60 or 66 for selectively regulating the operation of the housing 50.

In operation, the ports of the housing 50 selectively vent the inner volume thereof with the air within the commode tank 10. When the port 66 is sealed via stopper 70 fluid such as air and water is permitted to flow into and out of the housing 50 in a restricted manner through orifice 62. When the stopper 70 is sealably engaged in port 60 fluid is permitted to flow relatively unobstructed into and out of the housing 50 through orifice 68. The differential air flow characteristics provided with the ports 60 and 66 respectively permits selectivity in the desired flush mode. By permitting fluid to flow through port 66, the housing 50 merely becomes a passive element riding upon valve stem 42 and producing negligible effect upon the flushing operation of the valve 38. When port 66 is sealed from the environment air is permitted only to enter the housing 50 through orifice 62 whereby the housing 50 effectively functions as a weighted element during the flushing operation, as described in more detail below.

The housing 50 remains bouyant within the tank 10 because a trapped air space is provided above the bottom surfaces of the tubular ports 60 and 66 from which air is not permitted to escape in either mode of operation. In this manner, housng 50 will always float to the top surface of the water level 24 within the commode tank 10 if permitted. The water level within the housing 50 will also be substantially equivalent to that on the outside thereof when given sufficient time to equalize; either slowly through the venting or orifice 62 or rapidly through aperture 68. Once the handle 30 is actuated and the bulb 40 is removed from the valve seat 20, the water level 24 will begin to drop in tank 10, with the water egressing through the outlet pipe 18. The bouyancy of the bulb 40 will normally hold it above pipe 18 during the flushing operation. As the water level drops, the housing 50 will also begin to fall as its weight, with port 66 sealed, will be substantially increased by the trapped water therein. Since the orifice 62 is of a restricted size, the inner volume of the housing 50 will not permit rapid water level equalization with that outside. In ths manner the housing 50 will acquire substantial weight for driving the valve stem 42 and bulb 40 downwardly along with the water level 24 as it egresses. When the stop 52 engages the housing 50, and particularly the lower end of the tubular element 54, the bulb 40 will be driven back into the valve seat 20 for premature termination of the flush. Referring now to FIGS. 3-5, the above-referred to sequence is more clearly illustrated. In FIG. 3 it may be seen that the stopper 70 is disposed within the unrestricted port 66 for limited volume flushing. In this configuration, the housing 50 floats atop water level 24 with water level therein substantially equivalent thereto. In FIG. 4 the flushing actuation has been set into motion with drainage of the water from the commode tank 10 through the outlet pipe 18 with the bulb 40 being in an upwardly disposed position therefrom. The weight of the trapped water within the housing 50 and above the water level 24 then causes the housing 50 to move downwardly upon the valve stem 42 until coming in contact therewith.

In FIG. 5 the weight of the water filled housing 50 against the stop 52 has driven the valve stem 42 and bulb 40 back into the valve seat 20 to prematurely terminate the flush at the water level shown therein and some degree less than that normally provided in a full flush operation. It may be seen that the above-described flush volume is selectable via the position of the stop 52 upon the valve stem 42. It may also be seen that a full volume flush may be achieved not only by opening port 66, but also by holding handle 30 downwardly until the water level 24 drops below the bottom surface of the housing 50. In this manner, with housing 50 and bulb 40 upwardly supported by the handle 30 and respective lever arms, the water egresses until the housing 50 is vented from its open bottom whereby water is permitted to immediately escape.

It may further be seen that the above-described apparatus is equally adaptable to commode tanks 10 of different varieties. For example, in some commode tank structures the flush valve 38 is comprised of a "flapper" type bulb wherein a rigid valve stem 42 is not utilized. Such a commode structure is shown and described in U.S. Pat. No. 3,156,930 issued to C. J. Moutton on Nov. 17, 1964. As shown therein, the conventional valve bulb may be pivoted about the drain pipe and actuated with a chain, or the like. In such an application, the apparatus of the present invention could be easily adaptable by supporting the housing 50 above the valve bulb in a manner similar to that shown and described above.

It is thus believed that the operation and construction of the dual flush toilet mechanism of the present invention will be apparent from the foregoing description. While the apparatus shown and described has been characterized as being preferred, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the following claims.