Abstract:
A flush tank includes an outlet pipe attached to a receptacle for discharging water, a float disposed close to the outlet pipe to selectively block the outlet pipe, and to control an outward flowing of the water through the outlet pipe. A magnetically forcing device may magnetically force the float to block the outlet pipe, and a detecting device may be used to detect users and to actuate the magnetically forcing device to release the float. The magnetically forcing device includes an electromagnetic device supported by a frame to act with the float. A stop may be attached to the frame to limit a movement of the float relative to the outlet pipe.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a flush tank, and more particularly to a flush tank having an electromagnetic control device for easily controlling and actuating or operating the flush tank. 
   2. Description of the Prior Art 
   Various kinds of typical flush tanks have been developed and widely used nowadays, and comprise a float movable toward an outlet pipe, in order to control the water flushing of the flush tanks, and a coupling chain coupling the float to an actuating knob, in order to control the engagement or the disengagement of the float and the outlet pipe. 
   For example, U.S. Pat. No. 5,249,313 to Chang, U.S. Pat. No. 5,459,885 to Gaw, U.S. Pat. No. 5,524,297 to Harrison, and U.S. Pat. No. 5,924,143 to Harrison disclose four of the typical flush tanks and also comprise a float coupled to a coupling chain which may actuate the float toward and away from the outlet pipe. 
   In addition, for the typical flush tanks, the float may not suitably or solidly forced to block the outlet pipe when the gasket is aged, or when the water level within the water tank is not high enough, or the like. 
   Furthermore, the control devices for the typical flush tanks include a mechanical mechanism and is required to be provided and attached to the flush tank, and is required to be operated manually. The mechanical operation of the mechanical mechanism may make noised while in use. 
   The applicant has developed a typical flush tank having an electromagnetic control device for easily controlling and actuating or operating the flush tank, and disclosed in U.S. Pat. No. 6,237,165 to Chen et al. However, the typical electromagnetic control device for the flush tank is also required to be operated manually and includes a complicated configuration. 
   The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional flush tanks. 
   SUMMARY OF THE INVENTION 
   The primary objective of the present invention is to provide a flush tank including an electromagnetic control device for easily and automatically controlling and actuating or operating the flush tank. 
   In accordance with one aspect of the invention, there is provided a flush tank comprising a receptacle for receiving water therein, an outlet pipe attached to the receptacle for discharging the water, a float disposed close to the outlet pipe to selectively block the outlet pipe, and to control an outward flowing of the water through the outlet pipe. A magnetically forcing device may further be provided for magnetically forcing the float to block the outlet pipe, and a detecting device may be used to detect users and to actuate the magnetically forcing device to release the float automatically without being depressed or operated or actuated by the users. 
   The magnetically forcing device includes an electromagnetic device disposed in the receptacle for acting with the float. The float includes at least one projection extended therefrom for acting with the electromagnetic device. The magnetically forcing device includes a frame disposed in the receptacle to support the electromagnetic device, and for acting with the float. 
   The frame includes a casing provided therein to receive the electromagnetic device. The frame includes at least one block provided thereon and made of magnetically attractable material, the float includes at least one extension extended therefrom and made of magnetically attractable material for acting with the block. 
   A stop may further be provided and attached to the frame, for engaging with the float and for limiting a movement of the float relative to the frame. The frame includes at least one post extended therefrom, the stop includes at least one leg extended therefrom and adjustably secured to the post. The stop includes a loop attached to the leg and to slidably receive the post. 
   The post includes a plurality of apertures formed therein, the stop includes a catch provided on the leg to selectively engage into either of the apertures of the post, to adjustably secure the leg of the stop to the post. The leg includes a spring blade provided thereon to support the catch. The leg includes a hand grip provided on the spring blade to move the spring blade to disengage the catch from the leg. 
   The electromagnetic device includes a core for acting with the float, and a coil disposed around the core, to move the core relative to the coil. The electromagnetic device includes a housing to receive the core and the coil. The electromagnetic device includes a duct to receive the core. The duct includes a cushioning member disposed therein to engage with and to cushion the core. 
   The electromagnetic device includes a container having a cavity formed therein to slidably receive the core. A knob may further be provided and attached to the receptacle, and a chain coupled between the knob and the float. 
   Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided hereinbelow, with appropriate reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a flush tank in accordance with the present invention; 
       FIG. 2  is a partial cross sectional view illustrating the control device of the flush tank; 
       FIG. 3  is a perspective view of the control device for the flush tank; 
       FIG. 4  is a partial exploded view of the control device for the flush tank; 
       FIG. 5  is a top plan view of the control device for the flush tank; 
       FIG. 6  is a partial side plan view of the control device for the flush tank; 
       FIG. 7  is a partial cross sectional view taken along lines  7 — 7  of  FIG. 3 ; 
       FIG. 8  is a partial cross sectional view similar to  FIG. 7 ; illustrating the operation of the control device for the flush tank; and 
       FIG. 9  is a partial cross sectional view similar to  FIG. 2 ; illustrating the operation of the control device for the flush tank. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings, and initially to  FIGS. 1 and 2 , a flush tank in accordance with the present invention includes a receptacle  10  normally attached to a wall member  11 , and disposed above the rear portion of a toilet  12 , for receiving water to flush the toilet  12 . The receptacle  10  comprises a usual actuating knob  14  attached thereto, for controlling the flushing of the toilet  12 . 
   As shown in  FIGS. 2–4  and  9 , an outlet pipe  20  is normally attached or secured to the bottom portion of the receptacle  10  with one or more fasteners  21 , and includes a passage  22  formed therein for allowing the water contained in the receptacle  10  to flow out and to flush of the toilet  12  or for discharging the water. A usual overflow tube  23  is attached to the outlet pipe  20  to maintain a water level of the receptacle  10 . 
   A frame  30  is attached or secured to the receptacle  10 , such as secured to the outlet pipe  20  of the receptacle  10  with one or more stays  24 , and includes a space  31  formed therein to slidably receive a float  40  therein. The float  40  is disposed above or close to the outlet pipe  20  and includes a pad  41  attached to the bottom thereof, for engaging with the outlet pipe  20 , to control the water outward flowing through the outlet pipe  20 . 
   The frame  30  includes one or more, such as two blocks  32  provided thereon or extended therefrom, and made of metal or magnetic members or magnetically attractable materials for magnetically attracting purposes. The frame  30  further includes one or more, such as two blocks or casings  33  provided thereon or extended therefrom, and each having a chamber  34  formed therein ( FIGS. 5 ,  7 ,  8 ) to receive an electromagnetic device  50  therein. 
   As shown in  FIGS. 7 and 8 , each of the electromagnetic devices  50  includes a container  51  engaged into the chamber  34  of the corresponding casing  33  and having a cavity  52  formed therein, such as formed in the upper portion thereof. A housing  53  is engaged in the container  51  and includes an orifice  54  formed in the upper portion thereof and communicating with the cavity  52  of the container  51 . 
   Each of the electromagnetic devices  50  includes a duct  55  disposed in the housing  53 , a core  56  slidably received in the duct  55  and having an upper portion movable or engageable into the cavity  52  of the container  51 , and a coil  57  engaged around the core  56  or the duct  55 , for actuating the core  56  to move relative to the duct  55  and the housing  53  or the container  51 . 
   It is preferable that a resilient or cushioning member  58  is disposed in the lower portion of the duct  55 , and includes a depression  59  formed therein, to slidably receive the lower portion of the core  56 , and to cushion the core  56 , and to prevent the core  56  from impacting or hammering into the housing  53  or the container  51 . 
   The float  40  includes one or more, such as two extensions  42  provided thereon or extended therefrom, and made of magnetic members or magnetically attractable materials or metal for magnetically attracting or acting with the corresponding blocks  32  of the frame  30 . However, the magnetically attracting force between the extensions  42  of the float  40  and the blocks  32  of the frame  30  is smaller than the floating force or the buoyancy of the float  40 . 
   The float  40  further includes one or more, such as two projections  43  provided thereon or extended therefrom, and made of magnetic members or magnetically attractable materials or metal, or having a magnet  44 , such as a permanent magnet  44  disposed therein for magnetically attracting or acting with the electromagnetic device  50 . For example, when the electromagnetic device  50  is not energized, the magnetic core  56  of the electromagnetic device  50  may act with or may attract the projections  43  or the magnets  44  of the float  40  ( FIG. 7 ). 
   When the magnetic core  56  of the electromagnetic device  50  is acted with or attracted the projections  43  of the float  40 , and when the extensions  42  of the float  40  are also acted with the blocks  32  of the frame  30 , the magnetically attracting force between the extensions  42  and the blocks  32 , and between the core  56  and the projections  43  is arranged to be greater than the floating force or the buoyancy of the float  40 , in order to force the float  40  downwardly to block the outlet pipe  20  ( FIG. 2 ). 
   The flush tank further includes a sensor or detecting device  60  ( FIG. 1 ) attached to the wall member  11 , and preferably disposed above or close to the rear portion of the toilet  12 , for detecting whether the users are using the toilet  12  or not. The detecting device  60  is electrically coupled to the electromagnetic devices  50 , with such as wires  61  ( FIGS. 3 ,  4 ), for actuating the electromagnetic devices  50 . 
   For example, when the detecting device  60  has detected that a user is using the toilet  12 , the electromagnetic devices  50  may be actuated to force or to pull the core  56  into the duct  55 , and thus to separate the core  56  from the projections  43  or the magnets  44  of the float  40  ( FIG. 8 ). As shown in  FIG. 5 , the frame  30  may include one or more pathways  35  formed therein to receive the wires  61 . 
   When the core  56  is separated from the projections  43  or the magnets  44  of the float  40 , the magnetically attracting force between the extensions  42  of the float  40  and the blocks  32  of the frame  30  is smaller than the floating force or the buoyancy of the float  40 , and is thus not good enough to force the float  40  downwardly to block the outlet pipe  20 . At this moment, the float  40  may float upwardly away from the outlet pipe  20  ( FIG. 8 ), to allow the water in the receptacle  10  to flow out through the outlet pipe  20  and to flush the toilet  12  ( FIG. 9 ). 
   It is preferable that the core  56  may be formed into different polarity from that of the magnet  44  when the core  56  is separated from the projections  43  or the magnets  44  of the float  40 , or when the core  56  is forced into the duct  55  by the coil  57 , in order to further force the magnet  44  and the float  40  upwardly away from the frame  30  and the electromagnetic devices  50 . 
   After the water flushing operation, the float  40  may move downwardly to block the outlet pipe  20  again. The electromagnetic devices  50  may be switched off or de-energized when the float  40  floats upwardly away from the outlet pipe  20  to conduct the water flushing operation. At this moment, the core  56  is not acted by the coil  57 , and may be attracted to the magnet  44 , to solidly retain the float  40  to the frame  30 , and to solidly block the outlet pipe  20  again. 
   As shown in  FIGS. 2–4 , a usual pull chain  45  may further be provided and coupled between the float  40  and the actuating knob  14  ( FIG. 1 ), to allow the float  40  to be pulled and disengaged from the outlet pipe  20  manually by the users, and to allow the toilet  12  to be flushed by the water when the float  40  is pulled disengaged from the outlet pipe  20 . 
   As shown in  FIGS. 3 and 4 , the frame  30  may further include one or more, such as two posts  37  extended therefrom and each having one or more apertures  38  formed therein, and may further include a stop  70  adjustably secured thereto. For example, the stop  70  includes one or more, such as two legs  71  extended therefrom and each having a loop  72  provided thereon to slidably receive the posts  37 , and to slidably secure the stop  70  to the frame  30 . 
   The stop  70  includes one or more, such as two spring blades  73  formed in the legs  71  thereof respectively, and each having a catch  74  extended therefrom ( FIG. 4 ), for engaging into the corresponding apertures  38  of the posts  37 , and thus to adjustably secure the stop  70  to the posts  37  of the frame  30 . Each of the spring blades  73  may include a hand grip  75  extended therefrom, for pushing the spring blades  73  to disengage the catches  74  from the apertures  38  of the posts  37 , and thus to allow the legs  71  of the stop  70  to be slid and adjusted up and down along the posts  37 . 
   The stop  70  includes an opening  77  formed therein for receiving the usual pull chain  45 , and includes an inner peripheral shoulder  78  formed therein ( FIGS. 2 ,  9 ) for receiving the upper portion of the float  40 , and for limiting the movement of the float  40  relative to the frame  30 . 
   It is to be noted that the float  40  is allowed to be automatically floated or moved upwardly away from the outlet pipe  20  to allow the water in the receptacle  10  to flow out through the outlet pipe  20  and to flush the toilet  12  when the detecting device  60  has detected that a user is using the toilet  12 , such as when the user has been detected to use the toilet  12  and then moved away from the toilet  12 . The typical electromagnetic control devices for the flush tanks are still required to be operated manually. 
   In addition, the electromagnetic device  50  and the magnet  44  may be enclosed or shielded or covered or protected with plastic materials, to prevent the electromagnetic device  50  and the magnet  44  from being rusted. In addition, the core  56  is received in the container  51  and the housing  53 , and will not make noises while moving relative to the duct  55 . No typical flush tanks have a magnetically attracting device to force the float to block the outlet pipe. 
   Accordingly, the flush tank in accordance with the present invention includes an electromagnetic control device for easily and automatically controlling and actuating or operating the flush tank. 
   Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.