Abstract:
The float valve has a water inlet, a perforated bottom surface and a lift valve mounted between the water inlet and the bottom surface. A float and a rocker arm are used to raise and lower the disc of the lift valve in response to a water level inside the housing. The valve seat has a first vertical axis and the water inlet has a second vertical axis and the first and second vertical axes are parallel to each other and are spaced apart a distance corresponding substantially to a radius of the valve seat. In another feature, a stud on the rocker arm interferes with the valve stem when the float is in a down position, for leaning the valve stem away from the axes of the valve seat and of the water inlet.

Description:
FIELD OF THE INVENTION 
   This invention pertains to Christmas tree watering devices and more particularly, it pertains to a float valve connected to a hose and a funnel to fill the reservoir of a Christmas tree stand with water from an elevated position. 
   BACKGROUND OF THE INVENTION 
   Generally, a natural Christmas tree has lower branches that extend more than an arm&#39;s length around its stand. The tree stand is often covered with decorating paper and snow-imitating wool or is hidden by a manger. Wrapped gifts are stowed around the tree stand for several days and even weeks preceding Christmas eve. Therefore, the reservoir of a tree stand is hardly accessible to add water therein. 
   For all these reasons, a hose and a funnel are normally used to add water into the reservoir of a tree stand to keep the tree fresh and green during the entire holiday season. In most Christmas tree watering systems, a valve is mounted inside the reservoir of the tree stand to stop the flow of water from the hose and funnel when the water has reached a predetermined level inside the reservoir. The backflow of water inside the funnel indicates a full-reservoir condition. 
   Numerous Christmas tree watering systems have been developed in the past and have enjoyed varying degrees of success. Some watering systems of the prior art are known to occasionally fail to indicate a full-reservoir condition. This deficiency causes an overflow of water from the reservoir of the tree stand or from the funnel above the tree stand, to the floor. An overflow of water from the reservoir of the tree stand is a particular concern because that water often contains dissolved tree sap and other tree extracts which could stain a carpet permanently. 
   Christmas tree watering systems of a common type are described in the following documents; 
   U.S. Pat. No. 5,076,009 issued on Dec. 31, 1991 to Michael Cibor; 
   U.S. Pat. No. 5,522,179 issued on Jun. 4, 1996 to Peter R. Hollis; 
   U.S. Pat. No. 5,575,110 issued on Nov. 19, 1996 to Luc. M. Couture; 
   U.S. Pat. No. 6,073,390 issued on Jun. 13, 2000 to Stephen R. Baudier; and 
   U.S. Pat. No. 6,260,303 issued on Jul. 17, 2001 to George Lewis Sappenfield. 
   The type of Christmas tree watering systems described in these documents generally comprises a funnel on a Christmas ornament or at other elevated location along the tree. A hose is connected to the funnel and extends to a valve mounted inside the reservoir of the tree stand. The valve has a float therein moving with the water level inside the reservoir. The float carries a valve disc which coincides with the end of the hose, and blocks the end of the hose when the water in the reservoir rises to a predetermined level. 
   A second type of watering system is described in the U.S. Pat. No. 5,090,443 issued on Feb. 25, 1992 to Paul S. Jacobsen. This document discloses a float valve in which the end of the water hose is laying against a float. The float moves upward in a casing with the level of water in the reservoir of the tree stand, to bend the hose and block the flow of water inside the hose. 
   A third type of watering system is described in the U.S. Pat. No. 5,937,574 issued on Aug. 17, 1999 to David R. Jacques. This document discloses a float valve for a Christmas tree stand in which is mounted a float on the end of a lever. The lever is pivoted on a pin through its centre. A stud on the opposite end of the lever pushes a ball away from a valve seat thereby allowing a flow of water through the valve seat. As the float rises, the stud retracts and let the ball fall into the valve seat to block the flow of water through the valve seat. 
   In the prior art valves of the first and second types, the head pressure from the water inside the hose and the funnel forces the valve&#39;s flap or disc to open. In this arrangement, the inertia of a rush of water in the hose, such as in the case of an unsteady filling of the funnel, tends to open the valve, even when the float is partly submerged. Therefore, in order to properly close the valve, the float must first gain sufficient buoyancy to overcome this head pressure. 
   In the prior art valve of the third type, the inflow of water in the hose acts directly against the ball of the valve forcing it to close unexpectedly or prematurely, thereby generating an overflow of water over the rim of the funnel. 
   As such, it may be appreciated that there continues to be a need for a new and improved float valve which is not susceptible of slow closure because of a head pressure and is not susceptible of premature closure from a flow surge inside the inlet hose. 
   SUMMARY OF THE INVENTION 
   The float valve according to the present invention comprises a lift valve wherein the valve disc closes against a valve seat in a same direction as the flow of water through the valve seat, and wherein the valve stem and disc are movable sideways from the flow of water to avoid the force of the flow of water through the valve seat. A movement of the float with the rising water pulls the valve disc back into the flow of water such that this flow assists the float in closing the valve. The float valve is thereby reliable for indicating a full-reservoir condition in a timely manner. 
   In accordance with one feature of the present invention, there is provided a float valve for use in a Christmas tree watering system. The float valve comprises a housing having an upper portion, a water inlet in the upper portion, and a perforated bottom surface. A lift valve inside the float valve has a circular valve seat between the water inlet and the perforated bottom surface; a valve disc mounted between the water inlet and the valve seat and a valve stem extending from the valve disc through the valve seat. 
   The float valve according to the present invention also has a mechanism to raise and lower the valve disc in response to a water level inside the housing. In this arrangement, the valve seat has a first vertical axis and the water inlet has a second vertical axis and the first and second vertical axes are parallel to each other and are spaced apart a distance corresponding substantially to a radius of the valve seat. 
   Because of this structure, the flow of water through the valve seat is offset from the valve seat and from the valve disc whereby it is less susceptible of applying a force on the valve disc in a closing direction, when the valve seat is fully open. 
   In accordance with another feature of the present invention, the mechanism to raise and lower the valve disc comprises a float and a rocker arm pivotally connected to the housing, to the float and to the valve stem for a seesaw movement with the float and the valve stem. The rocker arm has a clevis on one end thereof. The valve stem is pivotally mounted in the clevis and the rocker arm has a stud thereon adjacent the clevis. The stud interferes with the valve stem for blocking a movement of the valve stem in the clevis and for leaning the valve stem away from the axis of the water inlet. 
   When the float is in a lower position, the valve disc is positioned away for the flow of water through the valve seat and does not restrict the flow of water through the valve seat. When the float rises to a prescribed level, however, the float pulls the valve stem and the valve disc back into the axis of the valve seat whereby the flow of water through the valve seat helps to close the valve. 
   Upon closure of the valve, the water level rises quickly into the hose and the funnel at a same rate as the water added into the funnel, to reliably indicate a full-reservoir condition. 
   Still another feature of the float valve of the present invention is that it is susceptible of a low cost of manufacture with regard to both materials and labour, and which accordingly is then susceptible of low prices of sale to the consumer, thereby making such float valve economically available to the public. 
   Other advantages and novel features of the present invention will become apparent from the following detailed description of the preferred embodiment. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     One embodiment of the present invention is illustrated in the accompanying drawings, in which like numerals denote like parts throughout the several views, and in which: 
       FIG. 1  illustrates a Christmas tree and a preferred tree watering system comprising the float valve according to the preferred embodiment; 
       FIG. 2  is a perspective view of the float valve according to the preferred embodiment with the housing broken away to illustrate the internal structure thereof; 
       FIG. 3  is a cross-section view of the preferred float valve in a closed mode, as seen along a vertical plane passing widthwise through the valve housing; 
       FIG. 4  is another cross-section view of the float valve, in an open mode; 
       FIG. 5  is a perspective view of the clip holding the housing halves together. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will be described in details herein one specific embodiment, with the understanding that the present disclosure is to be considered as an example of the principles of the invention and is not intended to limit the invention to the embodiment illustrated and described. 
   Referring to  FIG. 1 , one best mode of using the float valve of the present invention in a Christmas tree watering system is illustrated therein. In this illustration, the float valve  20  is mounted inside a tree stand reservoir  22  and is retained to the rim of the tree stand reservoir by a clip  24 . A hose  26  extends from the float valve  20  to a funnel  28  mounted at a convenient height in the Christmas tree  30 . In the preferred embodiment, the hose  26  is coloured to blend in with the branches of the tree and the funnel  28  is decorated as a Christmas ornament. Water is added into the funnel  28  until the float valve shuts off and a backflow of water is observed in the funnel  28 . The height of the float valve  20  is selected so that the reservoir  22  contains a proper level of water therein when the backflow is observed in the funnel  28 . The content of the funnel  28  and of the hose  26  may then seep down slowly into the tree stand reservoir  22  without overfilling the reservoir. 
   Referring now to  FIGS. 2–4  simultaneously, the structural arrangement and operation of the float valve  20  according to the preferred embodiment will be described in details. 
   The float valve  20  has a housing  32  made of an upper half  34  and a lower half  36  joined together at a horizontal seam  38 . The seam  38  preferably comprises a ridge and groove lock  40  such that the two halves  34 ,  36  are separable from each other for periodically cleaning the interior of the valve housing  32 . 
   The upper portion of the upper half  34  comprises a valve compartment  42  which is covered by a cap  44 . A hose nipple  46  extends upward from the cap  44 . The lower half  36  of the valve housing  32  has a perforated bottom surface  48  which is illustrated in  FIG. 2 . In use, water is introduced in the valve housing  32  through the hose nipple  46  and flows out of the housing through the perforations in the bottom surface  48 . 
   The upper half  34  of the valve housing  32  has a pair of holed tabs  50 , holding a rocker arm  52  by its middle segment. The upper half  34  of the valve housing  32  also has a float guiding cavity  54  in which is mounted a cylindrical float  56 . The float  56  is free to move up and down according to the level of water in the housing  32 . The upper half  34  of the valve housing  32  has a vent hole  58  in the upper wall thereof to evacuate trapped air from the float guiding cavity  54  during the movement of the float  56 . 
   The rocker arm  52  has a rounded end  60 , a transverse shaft  62  through its middle segment and a clevis  64  on the other end thereof. That other end is also referred to as the clevis end. The transverse shaft  62  is mounted in the holed tabs  50  for a seesaw movement of the rocker arm about the holed tabs  50 . 
   The float  56  has a socket  66  in its side in which is engaged the rounded end  60  of the rocker arm  52 , for causing the rocker arm  52  to move with the float  56 . 
   The float valve  20  also comprises a valve stem  68  with a lower thick end  70  and a valve disc  72  mounted on the upper end of the stem  68 . 
   The thick lower end  70  is pivoted in the clevis  64  of the rocker arm  52 . The valve stem  68  has an appropriate length such that the valve disc  72  moves up and down inside the valve compartment  42  in response to a movement of the float  56  and the rocker arm  52 . 
   A valve seat  74  in the bottom surface of the valve compartment  42  creates a partition between the valve compartment  42  and the upper half  34  of the housing. 
   The valve stem  68 , the valve disc  72  and the valve seat  74  constitutes a poppet-type valve also referred to as a lift valve. 
   The valve stem  68  is further dimensioned to engage the valve disc  72  into the valve seat  74  and seal the valve seat  74  when the float  56  is in its upper position as illustrated in  FIG. 3 . It will be appreciated that an upward movement of the float  56  causes the rocker arm to tilt and to pull the valve stem  68  downward to close the valve seat  74  and to stop the flow of water between the valve compartment  42  and the upper and lower halves  34 ,  36  of the housing  32 . 
   A seep hole  76  which is illustrated in  FIG. 2  may be provided through the valve disc  72  to slowly drain the content of the hose  26  and of the funnel  28  following an addition of water to the reservoir  22  of a tree stand. Although a seep hole  76  is illustrated, it will be appreciated that the same result may be obtained with an imperfect seal between the valve disc  72  and the valve seat  74 . 
   Referring particularly to  FIG. 4 , the axis  78  of the hose nipple  46  is offset from the axis  80  of the valve seat  74  by a distance ‘A’ corresponding substantially to the radius of the valve seat  74 . The advantage of this offset is that only a limited portion of the water flowing into the valve compartment washes against the valve disc  72  and the corresponding downward force on the valve disc  72  is relatively small. 
   In order to further reduce the amount of water washing against the valve disc  72 , a short stub  82  is provided on the rocker arm  52  adjacent the clevis  64 . This short stub  82  pushes against the thick end  70  of the valve stem  68  when the rocker arm is tilted in the valve-open position as illustrated in  FIG. 4 , and causes the valve stem  68  and the valve disc  72  to lean away from the axis  78  of the hose nipple  46 . When the valve disc  72  is in this position, very little water washes against the valve disc  72  and only a negligible downward force is applied against the valve disc  72 . 
   Referring back to  FIG. 3 , the short stub  82  moves away from the thick end  70  of the valve stem  68  when the rocker arm  52  moves to a valve-closed position as illustrated in that drawing. Therefore the valve disc  72  is then free to align with the valve seat  72  to close the valve seat. When the rocker arm moves toward the position illustrated in  FIG. 3 , the valve disc  72  is brought back in alignment with the valve seat  74  and into the flow of water through the valve seat, whereby this flow enhances the closing of the valve seat  74  by the valve disc  72 . 
   For reference purposes, the size and material of the float  54  is selected such that its buoyancy causes the valve disc  72  to close the valve seat  74  when the water level inside the housing  32  is slightly above the seam  38 . 
   The clip  24  of the preferred valve  20  is illustrated in its entirety in  FIG. 5 . The clip  24  has an upper and lower identical grooves, labelled  84 ,  86  respectively. The grooves  84 ,  86  face each other and are separated by a riser  88  having a length substantially the same as the height of the upper and lower halves of the housing  32 . In use, the clip  24  mounts to the housing  32  to enclose the housing  32  and to keep both halves  34 ,  36  together. The upper groove  84  engages over a ridge  90  on the top of the upper half  34 , as best seen in  FIG. 2 . The lower groove  86  engages over a second ridge  92  which is only partly illustrated in  FIGS. 3 and 4 , extending over the exterior bottom surface of the lower half  36 . It will be appreciated from the illustrations that although the second ridge  92  is only partly illustrated, it has substantially a same cross-section as the first ridge  90  for engagement into a similar groove as for the first ridge. 
   In addition to keeping both halves together, the clip  24  is well fastened to the housing  32  by the engagement of the grooves  84 ,  86  and ridges  90 ,  92 , and is used to support the housing to the rim of a reservoir as previously illustrated. For this purpose the clip  24  has a curved lip  94  on its upper end opposite the upper groove  84  relative to the riser  88 . The curved lip  94  defines a hook  96  on the riser  88  for attachment to the rim of a tree stand reservoir. 
   All the components of the preferred float valve are made of plastic by injection molding for example. 
   As to other manner of usage and operation of the present invention, the same should be apparent from the the above description and accompanying drawings, and accordingly further discussion relative to the manner of usage and operation of the invention would be considered repetitious and is not provided. 
   While one embodiment of the present invention has been illustrated and described herein above, it will be appreciated by those skilled in the art that various modifications, alternate constructions and equivalents may be employed without departing from the true spirit and scope of the invention. Therefore, the above description and the illustrations should not be construed as limiting the scope of the invention which is defined by the appended claims.