Abstract:
A liquid level control apparatus for a flush tank includes a valve mechanism communicating with a fill tube and operable between open and closed conditions, two floats, at least one of which is coupled to the valve mechanism for closing it when the at least one float reaches a predetermined height, and structure interconnecting the floats so as to substantially prevent their vertical movement until a predetermined liquid level is reached corresponding to the predetermined height, thereby causing sudden movement of the at least one float to the predetermined height and sudden closing of the valve.

Description:
BACKGROUND 
   This application relates to apparatus for controlling the liquid level in vessels and, in particular, to such apparatus for use in toilet flush tanks. The apparatus disclosed herein is an improvement of those disclosed in U.S. Pat. Nos. 6,123,099 and 6,539,973. 
   The aforementioned patents disclose several types of valves utilizing a flexible, resilient pinch tube as a valve member, which is controlled by an actuator engageable with the outside of the tube to pinch it closed. Some of the embodiments disclosed in those patents utilize a float which encircles and moves along an upright fill tube. Upward movement of the float with rising water level is arrested until the water level reaches the desired shutoff level, whereupon the buoyancy force on the float overrides the arresting force so that the float suddenly moves to a shutoff positioned for effecting a snap-action shutoff of the valve. 
   While these prior arrangements have afforded a satisfactory snap-action shutoff, they require complex floats with plural tube passages therethrough, since the outlet of the pinch valve communicates with the tank through a separate tube externally of the fill tube, which also passes through the float. 
   SUMMARY 
   This application discloses a flush valve assembly which avoids the disadvantages of prior valve assemblies while affording additional structural and operating advantages. 
   In an embodiment, apparatus for controlling the level of liquid in a vessel having a fill tube communicating with the vessel and with a source of liquid, includes a valve mechanism communicating with the fill tube and operable between open and closed conditions relative to the fill tube, two floats in the vessel, at least one of the floats being coupled to the valve mechanism for moving the valve mechanism to its closed condition when the at least one float reaches a predetermined height, and structure interconnecting the floats so as to substantially prevent their vertical movement until a predetermined liquid level is reached corresponding to the predetermined height, thereby causing sudden movement of the at least one float to the predetermined height of the valve mechanism to the closed condition. 
   In an embodiment, apparatus for suddenly terminating filling of a vessel having a fill tube communicating with the vessel and with a source of liquid when a predetermined liquid level is reached, includes a valve mechanism communicating with the fill tube and operable between open and closed conditions relative to the fill tube, a first float coupled to the valve mechanism for effecting movement of the valve mechanism to its closed condition when the first float reaches a predetermined height in the vessel corresponding to the predetermined liquid level, and arresting mechanism including a second float cooperating with the first float to substantially prevent vertical movement of the first float until the predetermined liquid level is reached. 
   In an embodiment, the valve mechanism may include valve actuating mechanism having an arm, the second float having an aperture therein through which the arm extends, the arresting mechanism being responsive to initiation of vertical movement of the first float for shifting to an arresting condition wherein the second float is tilted sufficiently to cause the arm to bind in the aperture and prevent vertical movement of the floats, the buoyancy force on the second float when the predetermined liquid level is reached being sufficient to untilt the second float and unbind the arm, thereby to permit the first float to jump to the predetermined height. 
   There is also disclosed a method of suddenly closing an inlet valve to a vessel when a predetermined liquid level in the vessel is reached, including providing two floats in the vessel, coupling at least one float to the valve for closing the valve when the at least one float reaches a predetermined height in the vessel corresponding to the predetermined liquid level, and interconnecting the floats so as to prevent vertical movement of the at least one float until the predetermined liquid level is reached. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For the purpose of facilitating an understanding of the subject matter sought to be protected, there are illustrated in the accompanying drawings embodiments thereof, from an inspection of which, when considered in connection with the following description, the subject matter sought to be protected, its construction and operation, and many of its advantages should be readily understood and appreciated. 
       FIG. 1  is a fragmentary view of a flush tank including an embodiment of liquid level controlling apparatus, shown in side elevation, with parts shown in solid line in their position after draining of the flush tank and in broken line in their position after the tank has been refilled; 
       FIG. 2  is a slightly reduced top plan view of the apparatus of  FIG. 1 ; 
       FIG. 3  is a sectional view taken generally along the line  3 — 3  in  FIG. 2 ; 
       FIG. 4  is an enlarged sectional view taken generally along the line  4 — 4  in  FIG. 2 ; 
       FIG. 5  is a further enlarged fragmentary view similar to the right-hand side of  FIG. 3 , illustrating the float in its arrested position; 
       FIG. 6  is an enlarged top plan view of the right-hand side of the apparatus of  FIG. 2  with the valve cap and deflector removed; 
       FIG. 7  is a sectional view taken along the line  7 — 7  in  FIG. 5 ; 
       FIG. 8  is an enlarged bottom plan view of the valve cap of the apparatus of  FIG. 3 ; and 
       FIG. 9  is a sectional view taken along the line  9 — 9  in  FIG. 8 . 
   

   DETAILED DESCRIPTION 
   Referring to  FIGS. 1 and 2 , there is illustrated a liquid level controlling apparatus in the form of a flush valve assembly, generally designated by the numeral  10 , for use in a vessel, such as a toilet flush tank  11 , for controlling refilling of the flush tank subsequent to a flushing operation. The tank  11  has a bottom wall  12  and a peripheral side wall (not shown) and contains water which fills the tank  11  to a predetermined full level  15 . The flush tank may be provided with an overflow pipe  16 , which extends through a complementary opening in the bottom wall  12  and projects upwardly therefrom into the tank and communicates, by a suitable means, with the toilet bowl (not shown), all in a known manner. 
   Referring also to  FIGS. 3–6 , the flush valve assembly  10  includes an input conduit in the form of an adjustable-height fill pipe assembly  20 , which includes an upstanding fixed pipe  21  having a radially outwardly extending annular flange  22  and a cylindrical collar  23  which depends from the flange  22  and is receivable in a complementary opening in the bottom wall  12 . Depending from the collar  23  is an externally threaded stem  24  for coupling to an associated pressurized water source. In use, a gasket  25  is disposed between the annular flange  22  and the upper surface of the bottom wall  12 , and the pipe  21  is secured in place by a washer  26  and a nut  27 , all in a known manner. The bottom wall aperture for the fill pipe assembly  20  is disposed at a predetermined distance from the aperture for the overflow pipe  16 , which distance is standard in almost all flush tanks currently sold in the United States. 
   Projecting radially outwardly from the outer surface of the pipe  21  at equiangularly spaced-apart locations thereon are four rows of vertically-spaced adjustment lugs  28 . A circumferential groove is formed in the outer surface of the pipe  21  adjacent to its upper end for receiving an O-ring seal  29  ( FIG. 3 ). The upper end of the fixed pipe  21  is telescopically received in the lower end of an adjustable pipe  30 . More specifically, the pipe  30  has a central cylindrical bore  31  provided with an enlarged-diameter cylindrical counterbore  32  at its lower end, in which the fixed pipe  21  is received. The adjustable pipe  30  is provided at its lower end with four equiangularly spaced and radially inwardly projecting lugs  33 . The central bore  31  is provided at the upper end of the pipe  30  with a frustoconical counterbore  34 , which communicates with a recess  35  which is rectangular in transverse cross section. The upper end of the pipe  30  has a large-diameter cylindrical counterbore  36 , which defines an annular seat surface  37  at the upper end of the rectangular recess  35 . Extending longitudinally through the pipe  30  parallel to the longitudinal axis thereof are six circumferentially spaced cylindrical channels  38 . The upper end of the adjustable pipe  30  is externally threaded, as at  39 . 
   The adjustable pipe  30  is provided with a skirt or a collar  40 , which includes an annular flange  41  projecting radially outwardly from the pipe  30  just below the external threads  39 , and is integral at its outer edge with a depending cylindrical flange  42 . As can best be seen in  FIGS. 3 ,  5  and  6 , the flanges  41  and  42  have a rectangular notch  43  formed therein, closed by a bottom or base wall  44  which is parallel to the annular flange  41 . The skirt also includes a pair of upstanding rectangular lugs  45  on opposite sides of the base wall  44  having aligned pivot holes therethrough. Extending into the adjustable pipe  30  just about the base wall  44  is a radial aperture  47 , which communicates with the recess  35  (see  FIG. 5 ). Depending from the cylindrical flange  42  and from the base wall  44  is a frustoconical flange  48 . 
   In assembly of the fill pipe assembly  20 , the fixed pipe  21  is fitted up inside the counterbore  32  of the adjustable pipe  30 . In this regard, the adjustable pipe  30  is rotationally oriented so that its lugs  33  are aligned between the rows of lugs  28  on the fixed pipe  21 . Then the adjustable pipe  30  is lowered to the desired height and rotated ¼turn to bring the lugs  33  into alignment with the rows of lugs  28  for resting on the selected ring of lugs  38 . It will be appreciated that the O-ring  29  provides a fluid-tight seal between the pipes  21  and  30 . 
   The flush valve assembly  10  includes a valve mechanism  50  ( FIG. 3 ), which includes a valve housing insert  51 , a valve member  55 , a cap  60  and a deflector  70 . The valve housing insert  51  is a rectangular block dimensioned to fit in the rectangular recess  35  in the adjustable pipe  30  and has an axial, somewhat dumbbell-shaped channel  52  extending therethrough for communication with the counterbore  34  and the bore  31  in the adjustable pipe  30 . Also formed in the valve housing insert  51  is a side slot  53  ( FIGS. 4 and 5 ), which communicates with the center of the axial channel  52  and, in use, is positioned for alignment and communication with the radial aperture  47  in the adjustable pipe  30 . 
   The valve member  55  is shaped complementary to and is mateably received in the axial channel  52  of the valve housing insert  51 . The valve member  55  is formed of a flexible and resilient material, such as a suitable rubber or elastomer, and is supported by the valve housing insert  51 , which may be formed of a suitable rigid plastic material. The valve member  55  has a central cylindrical neck  56  joining frustoconical portions  57 , which in turn respectively communicate with cylindrical portions  58 , all of which portions are snuggly disposed in complementary-shaped portions of the valve housing insert  51 . The cylindrical portions  58  respectively communicate with frustoconical portions  59 , the lower one of which is snuggly received in the frustoconical counterbore  34  in the adjustable pipe  30 . 
   Referring also to  FIGS. 8 and 9 , the cap  60  has a cylindrical stem  61  integral at its upper end with an enlarged-diameter head  62  which has diametrically-opposed arcuate cutouts  63  therein. A cylindrical bore  64  extends axially through the cap  60  and is provided at the stem end with a frustoconical counterbore  65 . Formed in the distal end face of the stem  61  is a rectangular recess  66 . 
   In assembly, the cap  60  is fitted in the upper end of the adjustable pipe  30 , with the stem  61  seated on the seat surface  37  and the head  62  resting on the upper end of the adjustable pipe  30  (see  FIGS. 3 and 5 ). The cap  60  is rotationally oriented so that the cutouts  63  are respectively aligned with the groups of the longitudinal channels  38  in the adjustable pipe  30  (see  FIG. 4 ). In order to ensure this orientation, the rectangular recess  66  is shaped and dimensioned to mateably receive the upper end of the valve housing insert  51 , with the upper frustoconical portion  59  of the valve member  55  snugly seated in the frustoconical counterbore  65  of the cap  60 . 
   The deflector  70  has an elongated cylindrical body  71 , the lower end of which is internally threaded, as at  72 , and the upper end of which is closed by a dome-shaped end wall. Referring also to  FIG. 7 , equiangularly spaced-apart vanes  73  project radially inwardly from the cylindrical body  71 , each vane having a tapered or angled bottom edge  74 . An axial hole  75  is formed in the end wall. A cylindrical nipple  76  projects radially outwardly from the cylindrical body  71  adjacent to the end wall and defines a radial passage  77 , which communicates with the interior of the deflector  70  and is adapted to be coupled by a suitable flexible tube  78  to the upper end of the overflow pipe  16 , as can best be seen in  FIGS. 1–3 . 
   In assembly, the lower end of the deflector  70  is threadedly engaged with the upper end of the adjustable pipe  30  until the tapered bottom edges  74  of the vanes  73  engage the head  62  of the cap  60 , thereby holding the cap  60  in place which, in turn, holds the valve housing insert  51  and the valve member  55  in place. 
   The valve mechanism  50  also includes a valve actuating mechanism  80 , including an elongated push rod  81  which extends through the radial aperture  47  in the adjustable pipe  30  and through the side slot  53  in the valve housing insert  51  for engagement with the neck  56  of the valve member  55 . The push rod  81  has an enlarged head  82  at the outer end thereof. The valve actuating mechanism  80  also includes a cam member  83 , having a circular plate  84  with a flat rear side  85  and disposed for pivotal movement about the axis of a pivot pin  86 , which extends through an eccentric opening in the plate  84  and is journaled in complementary bearing holes in the lugs  45 . The flat side  85  of the circular plate  84  is disposed for engagement with the head  82  of the push rod  81  (see  FIG. 5 ). Integral with the circular plate  84  and extending downwardly and laterally outwardly therefrom is an extension arm  87 . 
   The valve actuating mechanism  80  also includes a generally cylindrical float  90  which is disposed coaxially about the overflow pipe  16  for axial movement therealong. The float  90  has an inner cylindrical wall  91  and an outer cylindrical wall  92  joined by an annular top wall  93 . Depending from the walls  91  and  92  at diametrically opposed locations are tabs,  94 , respectively provided with holes  95  formed therethrough (see  FIG. 4 ). The float  90  is coupled to the cam member  83  by a connecting rod  100 , which may be somewhat Z-shaped, having an upper portion  101  connected to the extension arm  87 , an intermediate portion  102  and a lower clevis portion  103  ( FIG. 2 ), which has a bight  104  and a pair of depending legs  105  which, respectively, extend through the holes  95  in the tabs  94  and terminate at downturned tips  106 . 
   In operation, it will be appreciated that, when the tank  11  is refilling after a flush, when the water in the tank reaches a predetermined level  107 , it will exert a buoyancy force on the float  90  which will cause it to begin to rise vertically along the overflow pipe  16 . This movement will tend to pivot the connecting rod  101  and the cam member  83  in a clockwise direction, as viewed in  FIG. 1 , which will tend to move the valve mechanism  50  to a closed position, as will be explained more fully below. 
   It is a significant aspect of the flush valve assembly  10  that, as the water level starts to move above the level  107 , the movement of the valve mechanism  50  toward its closed position is arrested until the water reaches the full level  15  ( FIG. 1 ). In this regard, there is provided an arresting float  110 , which is disposed about the upper end of the fill pipe assembly  20  and the deflector  70  for movement axially therealong. The float  110  includes an inner cylindrical wall  111  and an outer cylindrical wall  112  joined by an annular top wall  113  for cooperation to define an open-bottom annular chamber  114  ( FIGS. 3–5 ). Extending laterally outwardly from the outer cylindrical wall  112  is a radial projection  115 , which is integral at its outer end with a depending arm  116  which extends downwardly well below the lower ends of the cylindrical walls  111  and  112  and is provided adjacent to its lower end with a rectangular slot  117  formed therethrough. 
   In assembly, the float  110  is fitted down over the upper end of the fill pipe assembly  20  before installation of the deflector  70 , so that the float rests upon the annular flange  41  of the adjustable pipe  30 , as can be seen in  FIGS. 1 and 3 . The upper portion  101  of the connecting rod  100  is then fitted through the slot  117  and assembled with the extension arm  87  of the cam member  83 . 
   In operation, after a flush the flush tank  11  empties, in a known manner, and the floats  90  and  110  and the connecting rod  100  drop to the position illustrated in  FIGS. 1 ,  3  and  4 . In this regard, the downward or counterclockwise pivotal movement of the cam member  83  is limited by engagement with the skirt  40 . This also limits the downward movement of the connecting rod  100  and the float  90 . The parts may be dimensioned and arranged so that, in this post-flush condition, the upper edge of the slot  117  stops against the connecting rod  100  at a contact point  118  (see  FIG. 3 ), at which position there may be a slight clearance between the lower end of the slot  117  and the connecting rod  100 . 
   In this post-flush condition, the valve mechanism  50  is in an open condition and water flows freely from the associated source, upwardly through the fixed pipe  21 , the bore  31  in the adjustable pipe  30 , the valve member  55  and the cap  60  into the deflector  70 . The deflector vanes  73  serve to break up the water flow and distribute the force exerted on the deflector  70 . A majority of the water entering the deflector  70  drops back down through the cutouts  63  in the cap  60  and then downwardly through the channels  38  in the adjustable pipe  30  into the tank  11  for refilling the tank. A smaller portion of the water entering the deflector  70  exits through the nipple  76  and the bowl fill tube  78  into the overflow pipe  16 , and then back down into the toilet bowl for refilling the bowl. 
   When the water in the tank  11  reaches the level  107  ( FIG. 1 ), the buoyancy force on the float  110  tends to lift it, thereby tending to pivot the connecting rod  100  in a clockwise direction, as viewed in  FIG. 1 , which tends to put upward pressure on the depending arm  116  of the arresting float  110 . Because of the eccentric location of the slot  117  relative to the central axis of the float  110 , this upward pressure tends to tilt the float  110  in a clockwise direction, as can best be seen in  FIG. 5 , causing the lower end of the slot  117  to contact the upper portion  101  of the connecting rod  100  at contact point  119 . Thus, in this tilted position, the connecting rod  100  engages both the top and the bottom of the slot  117  at the contact points  118 ,  119 , creating a binding which arrests upward movement of the connecting rod  100  and the float  110  thereby, in turn, arresting upward movement of the float  90 . The tilted position of the parts is shown exaggerated in  FIG. 5  for purposes of illustration. In actual practice, this tilting movement may be extremely small, so as to be barely noticeable to the naked eye. 
   When the water level in the tank  11  reaches the full level  15 , the buoyancy force exerted on the float  110  will cause it to level itself, breaking the bind between the connecting rod  100  and the slot  117 , thereby permitting the floats  90  and  110  to rise. The floats  90  and  110  will thereupon suddenly jump to the dotted-line positions illustrated in  FIG. 1 , thereby pulling the connecting rod  100  up and pivoting the cam member  83  in the clockwise direction, as viewed in  FIGS. 1 ,  3  and  5 . This pivotal movement about the axis of the pivot pin  86  will cause the upper edge of the flat side  85  of the circular plate  84  to move downwardly to the right against the head  82  of the push rod  81 , driving the push rod  81  to the right for pinching closed the neck  56  of the valve member  55 , shutting off the flow of water through the valve member  55 , in a known manner. This movement of the parts from the solid-line to the broken-line position in  FIG. 1  will occur almost instantaneously, causing a snap-action shutoff of the valve mechanism  50 . 
   An umbrella valve (not shown) may be installed in the upper end of the deflector  70  for normally closing the axial hole  75 . In the event that a low pressure should develop upstream of the valve member  55  while the valve is open, this low pressure will open the umbrella valve, exposing the interior of the deflector  70  to ambient air pressure through the axial hole  75 , and preventing siphoning of water from the tank  11  back through the channels  38  in the adjustable pipe  30 . 
   In a constructional model of the flush valve assembly  10 , the parts may all be formed of suitable plastic or elastomeric materials. However, the connecting rod  100  and the cam member  83  could be formed of an easily machineable metal, such as brass, to ensure adequate stiffness. It can be seen that the fill pipe assembly  20  and deflector  70  and the overflow pipe  16  serve as guides for the vertical movement of the floats  90  and  110 . While substantially cylindrical floats are illustrated, it will be appreciated that other shapes could be utilized and, while floats with open-bottom chambers are illustrated, other types of floats, such as those with closed buoyancy chambers, could also be used. 
   From the foregoing, it can be seen that there has been provided an improved flush valve assembly which is of relatively simple and economical construction, accomplishes snap-action shutoff of the flush valve and is usable, without modification, in almost all flush tank arrangements currently sold in the United States. 
   The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. While particular embodiments have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made without departing from the broader aspects of applicant&#39;s contribution. The actual scope of the protection sought is intended to be defined in the following claims, when viewed in their proper perspective based on the prior art.