Abstract:
A water removal system for removing water from an elevator pit that includes a sump, a pump, a pump input tube, a pump output tube and a switching mechanism. The sump at least partially extends below a lower surface of the elevator pit. The plump mounted outside of the elevator pit. The pump input line is operably connected to the sump and the pump. The pump output line is operably connected to the pump. The switching mechanism is mounted outside of the sump and is operably connected to the pump and the sump.

Description:
REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. Provisional Applic. No. 60/987,851, filed Nov. 14, 2007, the contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to a water removal system. More particularly, the invention relates to an elevator pit water removal system. 
     BACKGROUND OF THE INVENTION 
     Elevators have gained significant popularity in modern society as the elevators enable persons even with limited physical capabilities to move between the floors in buildings. As elevators enable buildings to be much taller, society has been able to form into more densely populated business and residential configurations. 
     Since it is often desirable for the elevators to service all of the floors in a particular building, it is necessary for a pit to be formed beneath the elevator that is adapted to receive a lower portion of the elevator that is below the floor of the lowest level. 
     Depending on the area in which the building is located, water may be present in the ground that is located beneath the building. Because of the position of the elevator pit beneath the ground level, the presence of water surrounding the elevator pit may cause water to leak into the elevator pit. If such water is not removed from the elevator pit, the water may cause degradation of the elevator components that are located in the elevator pit and thereby impact the safe operation of the elevator. 
     The ground water may exert hydronic pressure on the components of the building and, if not released, may cause damage to the components of the building. Such damage may ultimately render the building uninhabitable. 
     One technique for removing water from an elevator pit involves placing a pump in the elevator pit. While this option enables water to be removed from the elevator pit, the building/elevator codes in many parts of the country do not permit mechanical devices other than elevator related equipment to be placed in the elevator pit. 
     One technique that has been utilized to prevent water from entering the elevator shaft is applying a waterproof coating to the walls and floor of the elevator shaft. While this technique may restrict water from entering the elevator shaft, this technique often fails due to hydronic pressure caused by water in the ground surrounding the elevator pit. 
     Because of the building components that surround the elevator pit, it is often not possible to excavate the area surrounding the elevator pit to install other water removal systems. Additionally, worker protection regulations also would necessitate the length and width of such a hole to be impermissibly large. 
     SUMMARY OF THE INVENTION 
     An embodiment of the invention is direct to a system for removing water from an elevator pit. The water removal system may include a sump basket, a pump assembly and a water level sensor. The sump basket may be located in or under the elevator pit. The pump assembly removes water from the sump basket. The water level sensor controls the operation of the pump assembly based upon the level of water in the sump. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic illustration of a water removal system according to an embodiment of the invention. 
         FIG. 2  is a side view of an alternative configuration of the pump inlet tube and the pressure sensor tube. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the invention is directed to a water removal system, as illustrated at  10  in the Figures. While the water removal system is particularly suited for use in conjunction with an elevator pit  12 , the water removal system  10  may be adapted for other applications in which water must be removed. 
     The water removal system  10  includes a sump basket  20  that is installed in a lower surface  22  of the elevator pit  12 . The sump basket  20  is fabricated with a size that is adapted to receive the water that flows into the sump basket  20  without overflowing. The larger the width and depth of the sump basket  20 , the more water that can accumulate in the sump basket  20 . 
     In one configuration, the sump basket  20  has a cylindrical shape with a width and a height that are each between about 12 and 36 inches. In another configuration, the width and the height of the sump basket  20  are each between about 20 and 30 inches. 
     The sump basket  20  may be fabricated from a variety of materials such as plastic or concrete. Additionally, the sump basket  20  may be pre-fabricated or formed on site. To increase the safety of the elevator pit  12  and prevent objects from inadvertently entering the sump basket  20 , a sump lid  24  may be placed over the sump basket  20 . 
     While the sump lid  24  substantially covers the sump basket  20 , the sump lid  24  may permit water on the lower surface  22  of the elevator pit  12  to drain into the sump basket  20 . Drain tile from walls and/or floors may be tied into the sump basket  20 . 
     The water removal system  10  also includes a pump assembly  30  that is located outside of but in proximity to the elevator pit  12 . The size and capacity of the pump assembly  30  may be selected based upon a variety of factors such as a height the water must be lifted for discharge, the run over which the water must be pumped to reach the discharge and the volume of water that must be removed from the sump basket  20 . In one configuration, the pump assembly is a shallow well style pump. 
     The pump assembly  30  is operably connected to the sump basket  20  with a pump inlet tube  32 . The size and material from which the pump inlet tube  32  is fabricated are selected based upon the volume of water that must be removed from the stump basket  20 . In one configuration, the pump inlet tube  32  has a diameter of about one inch and is fabricated from copper. 
     Depending on the size of the elevator pit  12 , the pump inlet tube  32  may be mounted on the surface of the wall or floor of the elevator pit  12 . Alternatively, the p-ump inlet tube  32  may be mounted behind the wall or floor of the elevator pit  12 . 
     A pump outlet tube  34  is attached to the pump assembly. Water pumped out of the sump basket  20  using the pump assembly  30  may be directly discharged. Alternatively, depending on the composition of the water pumped out of the sump basket  20 , the water may need to be treated prior to discharge. 
     In certain embodiments, if the water contains contaminants such as oil that exceed applicable building or environmental codes, a separator sump  40  may be utilized to collect the water from the pump outlet tube  34  and then separate the contaminants from the water such as through settling. 
     In such a configuration, a separator pump  60  may be utilized to discharge water from the separator sump  40  using a separator sump outlet tube  62 . The separator pump  60  may have a variety of configurations such as being at least partially submersed in the separator sump  40 . Alternatively, it is possible for the water removal system  10  to utilize a trap to prevent the escape of sewer gas. 
     In many applications, it will not be necessary or desirable for the pump assembly  30  to run continuously. Operation of the pump assembly  30  may be controlled by a water level sensor that monitors the water level in the sump basket  20 . 
     In one configuration, the water level sensor utilizes a pressure sensor tube  50  that extends from the sump  40  to a pressure switch  52 . As the level of water in the sump basket  20  exceeds a specified level, the water pressure inside the end of the pressure sensor tube  50  inside the sump basket  20  raises and such pressure increase is transmitted to the pressure switch  52 , which controls the operation of the pump assembly  30 . 
     The size and material from which the pressure sensor tube  50  is fabricated are selected based upon the pressure sensitivity and the length of the pressure sensor tube  50 . In one configuration, the pressure sensor tube  50  has a diameter of about one half of an inch and is fabricated from copper. 
     Depending on the size of the elevator pit  12 , the pressure sensor tube  50  may be mounted on the surface of the wall or floor of the elevator pit  12 . Alternatively, the pressure sensor tube  50  may be mounted behind the wall or floor of the elevator pit  12 . 
     Because of the location of the pump inlet tube  32  and the pressure sensor tube  50  in the elevator pit  12 , it may be difficult to inspect these tubes. It may also be difficult to access the components of the water removal system  10  to ensure that they are operating correctly. To enable the evaluation operation of the water removal system  10 , the pump inlet tube  32  and/or the pressure sensor tube  50  may have a valve that may be used for introducing water into the sump basket  20  for testing the operation of the water removal system  10 . 
     As an alternative to separately mounting the pump inlet tube  32  and the pressure sensor tube  50  in the elevator pit  12 , it is possible to mount one of the tubes inside of the other tube for a portion of the length, as illustrated in  FIG. 2 . In one configuration, the pressure sensor tube  50  may be mounted inside of the pump inlet tube  32 , as the pressure sensor tube  50  is generally smaller than the pump inlet tube  32 . 
     As an alternative to configuring the water level sensor to operate using a hydraulic mechanism, it is possible to operate the water level sensor using other mechanisms. Examples of such alternative mechanisms for the water level sensor include pneumatic and optical. The pneumatic system could operate using a mechanism that is similar to the mechanism discussed above with respect to the hydraulic system. 
     An optical system could include a light source and a light sensor. The light source may be mounted outside of the elevator pit  12  to comply with building codes. The light can be directed from the light source to the light sensor using optical fibers. The presence of water interrupts the path of light between the light source and the light sensor such that it can be determined when the water level has reached a point where the pump  30  should be activated. 
     The water level sensor may include a high water alarm and a low water alarm such that the pump  30  is activated when the water level is higher than the high water alarm and deactivated when the water level is lower than the low water alarm. Alternatively, the pump  30  can be activated when the water level is higher than the high water alarm and then deactivated after a selected period of time. 
     The water level sensor thereby enables the water to be removed from the sump basket  20  without the use of mechanical devices placed inside of the sump basket  20 . The water removal system  10  thereby protects the components of the elevator that are located within the elevator pit  12  while complying with the applicable building codes. 
     In another configuration, the water level sensor utilizes a float (not shown) mounted in the sump basket  20 . Once the float rises above a specified level, the pump assembly  30  is activated. 
     In conjunction with the water removal system  10 , additional components may be utilized to protect the components of the elevator from damage caused by water accumulating in the elevator pit  12 . Such additional components include applying a waterproof sealant to the walls and floor of the elevator pit  12 . Another additional component is a drain tile system placed along the intersection of the walls and floor of the elevator pit  12 . One such drain tile system is available under the trademark BEAVER. 
     It is contemplated that features disclosed in this application, as well as those described in the above applications incorporated by reference, can be mixed and matched to suit particular circumstances. Various other modifications and changes will be apparent to those of ordinary skill.