# Patent

## Title
Automatic dual flush activation

## Abstract

A multi flush volume flush valve is in communication with an automatic flush control. The flush control determines the presence of a user and the amount of time the user uses the toilet. The usage time is compared to a predetermined time value to determine the appropriate flush volume based on an assumption regarding usage time and flush volume needs. The comparative value statistically adjusts to the restroom traffic.

## Background
CROSS-REFERENCE TO RELATED PATENT APPLICATION
This application claims priority from U.S. Provisional Patent Application No. 60/848,439, filed Sep. 29, 2006, herein incorporated by reference in its entirety.


FIELD OF THE INVENTION
The present invention relates generally to the field of flush valves in general. More particularly, the present invention relates to automatic control of a multiple-volume flush valve.
BACKGROUND OF THE INVENTION
Flush valves are used selectively to control the flushing of a urinal or toilet with a certain fixed volume of water. Typically, flush valves include a flexible diaphragm which forms a seal between the inlet and outlet, whereby a disruption of the diaphragm will result in a flow of water into the urinal or toilet to evacuate the waste.
Commercial toilets and urinals have traditionally utilized a single flush volume in their operations. This flush volume is designed to provide the maximum amount of water needed that may be needed to clear solid waste products. However, solid waste and liquid waste generally require different volumes of water to be cleared from the bowl. In a single flush system, the higher volume of water necessary to flush solid waste is also used to flush liquid waste, with the result that more water than is necessary is often used. Ideally, the smallest amount of water necessary to achieve an adequate flushing of the waste would be utilized.
While a multi-flush volume valve allows for a more efficient flush, it only achieves this efficiency if the appropriate flush mode is used with current multi-flush volume valves that are manually activated. In such systems, the proper flush volume is determined by the user; thus, manual actuation of the flush valve often results in an improper choice of flush volume. Users may be unaware of the dual flush system and, thus, do not appropriately use it. In addition, users may be aware of the system, but simply give no thought to how they are actuating the flush valve, but instead activate the device as they have in the past. Thus, there is a need for an automatic dual flush volume valve which allows for the selection of an appropriate flush volume based on the specific fixture use. Additionally, there is a need for an automatic dual flush volume valve that makes the proper decision of flushing volume.
SUMMARY OF THE INVENTION
One embodiment of the invention relates to an automatic system and method for automatically selecting between at least two flush volumes of gallons per flush (“gpf”). The system includes a multi-volume flushometer in operative communication with a flush control apparatus. The flush control apparatus determines if a user is present; and if the user is present, a timer is started. When the user is no longer detected, the timer is stopped and the elapsed time obtained is the usage time for that particular use. That usage time is compared to a predetermined usage time to determine the appropriate volume of flush to deliver.
These and other objects, advantages, and features of the invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a valve in accordance with one form of the invention;
FIG. 2 is a flow chart depicting a system in accordance with the principles of one embodiment of the present invention; and
FIG. 3 is a flow chart depicting the conditional subroutine logic for initial startup of the system comparison values.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to a flush valve system having at least two gallons per flush volumes (gpf, gallons per flush). Flush valve systems are generally known in the art, for example U.S. Pat. App. Pub. No. 2006/0151729, incorporated herein by reference. In addition, automatic sensor based flush valve actuation is also generally known, see for example U.S. Pat. No. 6,978,490, incorporated herein by reference. FIG. 1 illustrates one embodiment of a flushometer 11 of the present invention which includes a body 10 having an inlet 12 and an outlet 14. When installed the inlet 12 is connected to a water supply (not shown); and the outlet 14 is connected to a fixture (not shown) such as a toilet or urinal. A valve kit assembly is indicated generally at 16, and the valve kit assembly 16 generally includes a retaining disk, relief valve, sleeve guide, refill head, and a flow control ring. In the illustrated embodiment the valve kit assembly 16 comprises a diaphragm assembly 18. However, this could be other components well known in the art, such as a piston assembly (not shown), which meters water using a piston rather than a diaphragm. The valve kit assembly 16, shown in FIG. 1, includes a diaphragm 19 peripherally held to the body 10 by an inner cover 20. The diaphragm 19 is seated upon a shoulder 22 at the upper end of the body 10 by an inner cover 20. The diaphragm edge 52 of the diaphragm 19 is clamped in this position by the inner cover 20. An outer cover 21 is screw threaded onto the body 10 to hold the inner cover 20 in position compressing the diaphragm edges between the inner cover 20 and the shoulder 22.
The diaphragm assembly 18, as shown in FIG. 1, is closed upon a valve seat 26 formed at the upper end of a barrel 28. The barrel 28 forms the fluid conduit connecting the valve seat 26 with the outlet 14. The diaphragm assembly 18 further includes a relief valve 30 having a downwardly extending stem 32 telescopically carrying a movable sleeve 34. A handle assembly 37 of the present embodiment is described in further detail below. In general, a handle 38 is provided to actuate a plunger 36. The sleeve 34 is positioned for contact by the plunger 36 when operated by the handle 38. In one embodiment, the handle assembly 37 is retained on the body 10 by a nut 39.
The diaphragm assembly 18, in addition to the diaphragm 19 and the relief valve 30, includes a retaining disk 40, a refill ring 42 and a flow control ring 44. The underside of the retaining disk 40 is threadedly attached to a collar 46, which in turn is threadedly attached at its exterior to a sleeve guide 48 which carries the refill ring 42. The above described assembly of elements firmly holds the diaphragm 19 between an upper face 41 of the refill ring 42 and a lower facing surface 43 of the collar 46. Above the diaphragm assembly 18 is a pressure chamber 50 which maintains the diaphragm assembly 18 in a closed position when the flush valve 11 is not in use and the water supply is under pressure.
As is known in the art, when the handle 38 is operated, the plunger 36 will contact sleeve 34, tilting the relief valve 30 off its seat on the retaining disk 40. This will permit the discharge of water within the pressure control chamber 50 down through the sleeve guide 48. Inlet pressure will then cause the diaphragm 19 to move upwardly off the valve seat 26, permitting direct water communication between the inlet 12 and the outlet 14 through the space between the bottom of the diaphragm assembly 18 and the valve seat 26. The raising of the diaphragm 19 also lifts the relief valve sleeve 34, allowing it to clear the plunger 36 even if the user maintained the handle 38 in an actuated position. Once the valve sleeve 34 clears the plunger 36, the relief valve 30 reseats on the retaining disk 40. As soon as this operation has taken place, the pressure control chamber 50 will begin to fill through the filter 40 and bypass orifice 54 in the diaphragm assembly 18. As flow continues into the pressure chamber 50, the diaphragm assembly 18 will move back down toward the valve seat 26; and when it has reached that position, the flush valve 11 will be closed.
Various methods for achieving a plurality of flush volumes are known in the art. For example, U.S. Pat. App. Pub. No. 2006/0151729, which has been incorporated by reference, teaches angling the plunger to strike the stem at different points. The present invention is applicable with a wide variety of the known methods of providing multiple flush volumes.
In one embodiment of the present invention, systems and methods are used for determining the appropriate flush volume to apply using a multi-volume flushometer such as, but not limited to, those previously discussed. In one embodiment, the system includes a mechanism for determining the presence of a user. While there are a multitude of presence-aware sensors, examples of sensors that could be used with the present invention include: infrared, capacitance, weight, thermal, motion, and combinations thereof. Upon determination of presence, by a sensor, of a user, the system starts a timer. When the user is no longer detected, the timer is stopped to determine an elapsed “usage” time. This time is representative of the time the user was using the plumbing fixture. Given that a longer usage time tends to indicate solid waste rather than only liquid waste, a longer usage time will trigger a heavier flush volume.
In one embodiment, the system “learns” by averaging prior liquid uses and prior solid waste uses to determine the unique average for each type of use for that particular installation at that particular time. It will be appreciated that each installation of urinal or water closet may experience a unique use profile. For example, usage patterns concerning the type of waste may vary based on the relative position of the installation in the restroom.
By determining the usage time, designated tx, whenever an installation is used, the type of use (i.e. solid or liquid) can be ascertained and the appropriate flush volume used. In one embodiment, the time tx is compared to a predetermined average usage time above which represents solid waste and below which represents liquid waste. In a further embodiment, a unique average liquid waste and average solid waste usage times can be determined for each installation, designated tl, and ts, respectively. In one embodiment, time tx is compared to the predetermined average liquid waste usage time tl, wherein if the usage time is less than or equal to the time tl, a reduced flush volume is appropriate. In another embodiment, the usage time tx is compared to an average solid waste usage time ts, wherein if the usage time is more than the average solid waste usage time ts, a full flush volume is used.
In should be appreciated that in certain embodiments, initial “seed” values representing the liquid waste time and solid waste time are necessary. For example, when the system is first installed, no prior average usage time ts or tl will have been determined. Therefore, the system may be provided with preset times Tl and Ts, or even a Tp (singular system present value for comparison) which take the place of system averaged tl and ts, respectively, for determining the appropriate flush volume. In an exemplary embodiment, the preset value Tl is used upon power start up to represent detection time for solid waste evacuation. As mentioned before, a suitable substitute for this could be a singular system start up value Ts for comparison until the database is large enough to generate tl and ts. This value is used as the seed value (i.e. the initial starting point into which actual usage times tx are compared against) for determining when to flush a reduced volume. Similarly, the preset value Tl is used upon power start up to represent detection time for liquid waste evacuation. The value Tl is used as a seed value (i.e. the initial starting point into which actual usage values tx are later averaged into) for averaging liquid waste flush time average. As with ts and tl, in an exemplary embodiment, Ts>Tl. tl is the system average time calculated beyond a default start up value to use as comparison to determining liquid waste flushing condition, i.e. Tl<Ts embedded within the electronic flushometer logic is a routine called reduced flush logic. Thus, Tl or Ts are initially the values that tx is compared against.
In an exemplary embodiment, the system includes a counter Nc that keeps track of the number of flush cycles that the system has undergone since startup. Each time a new tx is determined, Nc is recalculated such that Nc=Nc+1. Nc is compared to a system assigned value Np to determine when a significant sample size of times tx has been accumulated. Nc can also be used as appropriate statistical values are necessary for the averaging routines. While the preset values Tl and Ts are used, the usage time tx for each use event is still used for averaging. For example, an initial usage event following installation of the system will utilize the preset values to determine the flush value. However, the usage time for that event tx will be averaged in to the appropriate preset value of Tl or Ts (depending on whether tx was greater or less than Tl) resulting in one of ts or tl as appropriate. This process continues with the preset values serving as the initial seed for the averaging of tx to form ts and tl (with each subsequent usage averaging the new tx into the ts or tl calculated originally from the preset value) and also being used to determine the flush volume (rather than the averages tl and ts which are being calculated “in the background”).
In an exemplary embodiment, after a preset number of cycles Np, i.e. when Nc is greater than Np, the system switches to using tl and ts to determine the flush volume rather than the preset values Tl and Ts. It will be appreciated that the number of cycles prior to the averages being used may be selected depending on the particular applications such that where usage times vary widely, a larger number of cycles are requires before the average is used and where usage times are consistent, a relatively fewer number of cycles are required prior to the averages being used.
In one embodiment, the device may trigger a flush of a specific volume after a predetermined amount of time even if the user is still detected. Such an intra-usage flush would serve to prevent clogging of the device where a large amount of material is being deposited. It should be appreciated that such a intra-usage flush should be of a minimal volume so as not to disturb the user.
FIG. 2 illustrates a flow chart of the logic for one embodiment of the present invention. The reduced flush logic is started at step 203 in FIG. 2. Next determination of a valid target (user) takes place at step 205. If no user is present, then the process logic jumps by returning back to step 203, essentially cycling until a user is detected. If a user is detected at step 205, then the Nc counter is indexed at step 207 and then a timer is started at step 207 to determine tx. When a user is no longer detected at step 209, the timer is stopped at step 211, setting tx. In one embodiment, the time tx for the first use after power up of the device is compared to the system “seed” value TL; after a predetermined number of usage cycles (chosen to provide a statistically significant averaging value), all subsequent comparisons are against the average tL rather than the seed value TL. In one embodiment, the time, tx, is stored at step 212. At step 213, the counter Nc is compared to a preset value Np such that if the counter is greater than the preset value, then the system moves to step 215 to compare tx to the average value tl, but if Nc is less than Np, the systems moves to step 214 for the comparison subroutine using the seed value TL.
FIG. 3 illustrates the subroutine for step 214 where at step 230 tx is compared to TL, and if it is greater than or equal to TL, the system goes to step 223 for a full flush and if less than, to step 217 for a reduced flush.
The time tx is compared to Tl at step 215. If tx is less than tl, then a reduced volume flush is performed at step 217. In one embodiment, the time, tx, is averaged into the time Tl in step 219 to generate a new average tl at step 221. If tx is greater than or equal to tl, then a full flush is performed at step 223.
In one embodiment, the newly acquired time tx is used to modify the existing time Ts or Tl depending upon its comparative value. In one embodiment, the time, tx, is then averaged into Ts or Tl at step 225 to generate a new Ts at step 227 or Tl at step 221.
The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments, and with various modifications, as are suited to the particular use contemplated.

## Claims

1. A system for controlling the flush volume of a flushometer, comprising:
a dual flush valve associated with a waste receptacle fixture, the dual flush valve having a solid waste flush volume corresponding to a full flush volume and a liquid waste flush volume corresponding to a reduced flush volume;
a presence detection sensor associated with the flush valve, the presence detection sensor configured to monitor for the presence of a user and provide a signal upon the detection of a user in a predefined area;
an automatic flush control in communication with the presence detection sensor and the dual flush valve, the automatic flush control comprising a memory unit associated with the presence detection sensor and the flush valve, the memory unit having stored therein computer program instructions for:
receiving the presence detection sensor signal;
initiating a usage timer upon the detection of the user;

stopping the usage timer upon no longer receiving a presence detection sensor signal; generating a usage time tx that equals time elapsed from initiation to stoppage of the usage timer when the user is no longer detected;
modifying a usage cycle count Nc by increasing Nc by 1;
determining if a number of cycles Nc is less than a predetermined number of cycles Np,;
if Nc<Np,
then determining if the usage time tx is greater than or equal to a preset usage time value Tp where if tx is greater than or equal to the preset value Tp, then the flush valve is opened for the full volume flush, and if tx is less than the preset value Tp, then the flush valve is opened for the reduced volume flush;
if Nc>Np,
then determining if the usage time tx is greater than or equal to a calculated average usage time tp where if tx is greater than or equal to the calculated average usage time tp, then a full volume flush is performed, and if tx is less than the predetermined average usage time tp, then the reduced volume flush is performed; and
modifying tp according to the value of tx,

wherein the automatic flush control provides instructions actuating the dual flush valve for the solid waste flush volume or the liquid waste volume based on usage time.

2. The system of claim 1, wherein Tp and tp further comprise a preset liquid waste use time value T1 and an average liquid waste use time value t1, respectively.

3. The system of claim 2, wherein modifying tp comprises modifying t1 based on tx to calculate a new t1.

4. The system of claim 1, wherein Tp and tp further comprise a preset solid waste use time Ts and an average solid waste use time value ts, respectively.

5. The system of claim 4, wherein modifying tp comprises modifying ts based on tx to calculate a new ts.

6. The system of claim 1, further comprising storing the time tx in a memory unit.

7. The system of claim 1, wherein detecting the user comprises the use of a sensor selected from the group consisting of infrared, capacitance, weight, thermal, motion, and combinations thereof.

8. The system of claim 1, wherein the memory unit further includes instructions to trigger a flush of a specific volume after a predetermined time even if a user is detected.