Swimming pool drain

Abstract

A sump for a swimming pool or spa includes a grate having an elongated slot for inflow of water at a low velocity high flow rate. A housing of relatively large capacity includes an outlet for conveying water to an oversized suction line to maintain the low velocity high flow rate to the junction with a conventionally sized standard suction line in fluid communication with a suction pump. A bypass line in fluid communication with the water in the pool or spa discharges water into the housing when the slot is sufficiently covered to prevent satisfying the flow rate into the suction line demanded by the pump and thereby prevent a level of suction at the slot sufficient to entrap clothing or a body part of a swimmer against the grate. The grate, a frame supporting the grate on the housing and the housing are devoid of elements that might cause entanglement of hair drawn into the sump. A hydrostatic valve may be coupled with the housing at locations of a pool or spa where the ground water level is sufficiently high to cause flotation of the pool or spa when partially filled or empty.

1 . A sump for use in a swimming pool or a spa, said sump comprising in combination: 
 a. a housing having an open upper end;    b. an outlet disposed in said housing;    c. an oversized suction line interconnecting said outlet with a conventionally sized suction line;    d. an inlet disposed in said housing coupled to a bypass line in fluid communication with the water in the swimming pool or spa;    e. a grate having a single elongated slot disposed therein for inflow of water to said housing; and    f. a frame for interconnecting said grate with said housing.    
     
     
         2 . The sump as set forth in  claim 1  including a hydrostatic valve and conduit coupled with said housing.  
     
     
         3 . The sump as set forth in  claim 1  wherein said outlet and said inlet are disposed at opposed ends of said housing.  
     
     
         4 . The sump as set forth in  claim 1  wherein said outlet an said inlet are disposed in the bottom of said housing.  
     
     
         5 . The sump as set forth in  claim 1  wherein said housing includes a sloping wall and an end and wherein said outlet and said inlet are disposed in said wall and said end, respectively.  
     
     
         6 . The sump as set forth in  claim 1  wherein said housing includes a wall and wherein said outlet and said inlet are coupled in said wall of said housing.  
     
     
         7 . The sump as set forth in  claim 6  including a shroud extending from a location proximate said wall at least partially surrounding said outlet for channeling water to said outlet.  
     
     
         8 . The sump as set forth in  claim 7  wherein said shroud is detachably attached to said housing.  
     
     
         9 . The sump as set forth in  claim 1  wherein said housing is rectangular.  
     
     
         10 . The sump as set forth in  claim 1  wherein said housing is cylindrical.  
     
     
         11 . The sump as set forth in  claim 1  wherein said housing is arcuate.  
     
     
         12 . The sump as set forth in  claim 1  including a ledge extending laterally at least partially about said housing.  
     
     
         13 . The sump as set forth in  claim 1  wherein said frame includes a skirt for insertion within said housing.  
     
     
         14 . The sump as set forth in  claim 1  wherein said frame includes a ledge extending laterally at least partially about said frame.  
     
     
         15 . The sump as set forth in  claim 14  wherein said frame includes a skirt for insertion within said housing.  
     
     
         16 . The sump as set forth in  claim 1  wherein said frame includes a ledge for supporting said grate.  
     
     
         17 . The sump as set forth in  claim 1  wherein said grate includes a pair of opposed end walls for defining the length of said slot.  
     
     
         18 . The sump as set forth in  claim 1  wherein said grate includes a pair of opposed side walls for defining the width of said slot.  
     
     
         19 . The sump as set forth in  claim 18  wherein said grate includes a pair of opposed end walls for defining the length of said slot.  
     
     
         20 . The sump as set forth in  claim 2  including a segregated compartment within said housing in fluid communication with said hydrostatic valve.  
     
     
         21 . The sump as set forth in  claim 20  including a secondary grate disposed at the upper end of said compartment for accommodating a flow of water from said hydrostatic valve into the pool or spa.  
     
     
         22 . The sump as set forth in  claim 1  wherein the flow rate of water through said slot is 1.5 feet per second and the volumetric flow rate is 60 gallons per minute.  
     
     
         23 . The sump as set forth in  claim 1  wherein said oversized suction line is configured to accommodate a water velocity rate of 1.5 feet per second and a flow rate of 60 gallons per minute.  
     
     
         24 . The sump as set forth in  claim 23  wherein said oversized suction line is approximately 4 inches in diameter.  
     
     
         25 . The sump as set forth in  claim 1  wherein the distance of water flow from said grate to the conventionally sized suction line is not less than 20 inches.  
     
     
         26 . The sump as set forth in  claim 25  wherein the distance of the water flow from said grate to the conventionally sized suction line is in the range of about 24 inches to about 30 inches.  
     
     
         27 . A method for draining water from a pool or spa through a sump in fluid communication with a suction pump via a suction line and a bypass line in fluid communication with the water in the pool or spa, said method comprising the steps of: 
 a. drawing the water to be drained through a grate having a single elongated slot;    b. conveying the water from the slot into a housing;    c. an oversized section of the suction line having an opening in the housing and the step of further drawing water from the housing into the oversized suction line;    d. further conveying the water from the oversized suction line to a junction between the oversized suction line and a conventionally sized suction line and through the conventionally sized suction line to the pump; and    e. providing fluid communication between the water in the pool or spa through an inlet in the housing in fluid communication with the bypass line.    
     
     
         28 . The method as set forth in  claim 27  wherein said step of drawing is carried out at a velocity of 1.5 feet per second.  
     
     
         29 . The method as set forth in  claim 28  wherein said step of drawing is carried out at a flow rate of 60 gallons per minute.  
     
     
         30 . The method as set forth in  claim 27  wherein said step of further conveying is carried out within the oversized suction line is at a velocity of 1.5 feet per second.  
     
     
         31 . The method as set forth in  claim 30  wherein said step of further conveying is carried out at a flow rate of 60 gallons per minute.  
     
     
         32 . The method as set forth in  claim 27  including the step of selectively introducing ground water into the pool or spa through the housing upon actuation of a hydrostatic valve.  
     
     
         33 . A method for installing a sump in a pool or spa having a suction line and a bypass line, said method comprising the steps of: 
 a. establishing a housing with the material defining a wall of the pool or spa;    b. attaching a frame to the housing at a height relative to the housing to locate the top of the frame substantially in the plane of the wall of the pool or spa;    c. securing a grate having a single slot in the frame;    d. interconnecting a length of an oversized suction line with the housing to convey water from the housing to a conventionally sized suction line; and    e. further interconnecting the bypass line with the housing.    
     
     
         34 . The method as set forth in  33  including the step of forming the housing from the material defining the wall of the pool or spa.  
     
     
         35 . The method as set forth in  33  including the step of forming the housing from cementitious material defining the wall of the pool or spa.  
     
     
         36 . The method as set forth in  35  including the step of stabilizing the location of the frame with setting material placed adjacent the cementitious material.  
     
     
         37 . The method as set forth in  33  including the step of securing a preformed housing with the material defining the wall of the pool or spa.  
     
     
         38 . The method as set forth in  33  wherein the pool or spa includes a liner and including the step of securing the frame to the liner.  
     
     
         39 . The method as set forth in  33  including the step of introducing ground water through the housing into the pool or spa upon actuation of a hydrostatic valve.  
     
     
         40 . A sump for use in a pool or spa, said sump comprising in combination: 
 a. a preformed housing having an open top, an outlet and an inlet;    b. a frame for engaging said open top of said housing;    c. a grate having a single slot; and    d. a ledge disposed within said frame for supporting said grate.    
     
     
         41 . The sump as set forth in  40  wherein said frame includes a depending skirt for slidably engaging the interior of said housing.  
     
     
         42 . The sump as set forth in  40  wherein said frame includes a laterally extending ledge for engagement by material surrounding said sump to retain said frame in fixed relationship to said housing.  
     
     
         43 . The sump as set forth in  40  wherein said slot extends for substantially the full length of said grate.  
     
     
         44 . The sump as set forth in  40  wherein said housing includes a bottom and wherein said outlet and said inlet are disposed in said bottom.  
     
     
         45 . The sump as set forth in  40  wherein said housing includes a pair of opposed end walls and wherein said outlet is disposed in one end wall of said pair of end walls and wherein said inlet is disposed in the other end wall of said pair of end walls.  
     
     
         46 . The sump as set forth in  40  wherein said housing includes a pair of opposed end walls and wherein both said outlet and said inlet are disposed in one end wall of said pair of end walls.  
     
     
         47 . The sump as set forth in  46  including a shroud disposed in said housing and extending from about said outlet toward the other end wall of said pair of end walls.  
     
     
         48 . The sump as set forth in  47  wherein said shroud is a cylinder.  
     
     
         49 . The sump as set forth in  47  wherein said housing includes a bottom and a pair of opposed side walls and wherein said shroud comprises a pair of joined sections extending from said bottom to one side wall of said pair of side walls.  
     
     
         50 . The sump as set forth in  40  wherein each of said housing, said frame and said grate are rectangular in plan form.  
     
     
         51 . The sump as set forth in  40  wherein each of said housing, said frame and said grate is circular in plan form.  
     
     
         52 . The sump as set forth in  51  wherein said slot is arcuate.  
     
     
         53 . The sump as set forth in  40  wherein each of said housing, said frame and said grate is arcuate in plan form.  
     
     
         54 . The sump as set forth in  53  wherein said slot is arcuate.  
     
     
         55 . A sump for use in a pool or a spa, said sump comprising in combination: 
 a. a cylindrical housing having a bottom;    b. an outlet and an inlet in fluid communication with said housing;    c. a further inlet disposed in said bottom;    d. a space extending from said bottom defined by a plurality of sections surrounding said further inlet;    e. a passageway adjacent the interior surface of said cylindrical housing and in fluid communication with said inlet and said outlet;    f. a wall extending from said plurality of sections to the inside surface of said cylindrical housing, said wall being disposed intermediate with said inlet and said outlet;    g. a shroud for attachment to the upper end of said cylindrical housing, said shroud including a slot in fluid communication with said passageway and an aperture in fluid communication with said space; and    h. a cap secured to said shroud and disposed at the top of said space, said cap including at least one slot disposed therein.    
     
     
         56 . The sump as set forth in  55  including a suction line connected to said outlet, a bypass line connected to said inlet and a hydrostatic valve connected to said further inlet.  
     
     
         57 . The sump as set forth in  55  wherein the pool includes a liner and a ring attachable to said cylindrical housing for capturing the liner between said ring and said cylindrical housing.  
     
     
         58 . The sump as set forth in  55  wherein said slot is arcuate.  
     
     
         59 . The sump as set forth in  55  including a first elbow connected to said outlet, a second elbow connected to said inlet, a first aperture disposed in said first elbow, a second aperture disposed in said second elbow, said first aperture being in fluid communication with said second aperture.