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This application claims foreign priority benefits from Canadian Patent Application 2,479,043, filed Aug. 24, 2004. 
   FIELD OF THE INVENTION 
   The present invention relates to a tub filler and overflow combination device for being supported within an opening formed in a tub wall of a bath tub for both filling the bath tub and providing an overflow drain to the bath tub through a common opening in the tub wall. 
   BACKGROUND 
   Bath tubs and other similar types of basins typically have hot water and cold water supply lines with either separate valves or a common valve provided for controlling flow of hot and cold water to a mixed outlet feeding a tub filler line. Bathtub spouts are then commonly mounted on the tub filler line. A separate drain waste and over flow system is typically provided having a drain at a bottom of the basin with a branch line extending upwardly to an over flow connection communicating through an opening in the tub wall spaced upwardly from the bottom of the tub. The overflow remains open to also act as a vent for the drain line. In general it is aesthetically unappealing to have both a spout and a separate overflow spaced apart along the tub wall. Furthermore installation requires unnecessary effort in forming two separate holes in the wall for plumbing the two components separately. 
   One known device is manufactured by Geberit Manufacturing Inc. of Michigan City, Ind., as described at http://www.us.geberit.com. The device provides a tub filler and an overflow within a common housing. To prevent back flow, a check valve is connected in series with the flow into the device in combination with a required vacuum breaker upstream and in series with the flow into the device, at higher elevation than the flood level of the tub, that is a top edge of the tub. The flow inlet of the tub filler is provided at a side of the device, perpendicular to the flow outlet into the tub, requiring extra elbow connectors and installation time as compared to a conventional spout. As the backflow prevention components of the check valve and vacuum breaker are required to be upstream from the device servicing would require messy and time consuming removal of components from the plumbing line buried within the wall. 
   SUMMARY 
   According to one aspect of the present invention there is provided a filler and overflow combination device for being supported within an opening formed in a tub wall, the device comprising: 
   a body having first and second portions; 
   mounting means for supporting the body to extend through an opening in a tub wall from the first portion of the body to the second portion of the body on opposing sides of the tub wall; 
   a flow passage extending through the body from a flow inlet at the first portion to a flow outlet at the second portion; 
   a drain passage extending through the body from a drain inlet at the second portion to a drain outlet at the first portion; and 
   a backflow prevention device supported in series with the flow passage, 
   the backflow prevention device being slidably removable from the body through the flow outlet. 
   The flow outlet and the drain inlet may be concentric with one another at the second portion of the body. Preferably, the flow inlet is parallel to the flow outlet such that the flow inlet and flow outlet are formed in opposing sides of the body. 
   By providing a backflow prevention device which is slidably removable through the flow outlet, the backflow prevention device can be readily serviced with minimal disassembly of the device and no destruction of the wall or plumbing line being required. By providing an inline connection of the flow inlet at the rear parallel and opposite from the flow outlet at the front, the device is readily manufactured and can be installed easily in a manner similar to conventional spouts. 
   The backflow prevention device may comprise a pair of check valves supported in series with one another. There may be provided a releasable retainer member retaining the backflow prevention device within the flow outlet. 
   According to a second aspect of the present invention there is provided a filler and overflow combination device for being supported within an opening formed in a tub wall, the device comprising: 
   a body having first and second portions; 
   mounting means for supporting the body to extend through an opening in a tub wall from the first portion of the body to the second portion of the body on opposing sides of the tub wall; 
   a flow passage extending through the body from a flow inlet at the first portion to a flow outlet at the second portion; and 
   a drain passage extending through the body from a drain inlet at the second portion to a drain outlet at the first portion; 
   the flow outlet and the drain intlet being concentric with one another at the second portion of the body; and 
   the flow inlet being parallel to the flow outlet such that the flow inlet and flow outlet are formed in opposing sides of the body. 
   There may be provided a cap member selectively mounted on the second portion of the body concealing the flow outlet and the drain inlet. 
   The cap member may include first and second chambers formed within an exterior body for communication with the flow outlet and the drain inlet respectively wherein each of the first and second chambers communication through the exterior body of the cap member by respective apertures formed therein. 
   The apertures in the exterior body are preferably all formed in a bottom side of the cap member. 
   The flow outlet may be connected with the first chamber by a suitable sealing member preventing direct flow from the flow outlet to the drain inlet within the cap member. 
   The cap member may be selectively mounted on the second portion of the body by a set screw for ready removal when replacing the components of the backflow prevention device. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings, which illustrate an exemplary embodiment of the present invention: 
       FIG. 1  is schematic view of the device as installed in a bathtub. 
       FIG. 2  is a partly sectional side elevational view of the device. 
       FIG. 3  is a front elevational view of the device. 
       FIG. 4  is a perspective view of the cap member showing the bottom side thereof. 
   

   DETAILED DESCRIPTION 
   Referring to the accompanying drawings, there is illustrated a tub filler and overflow combination device generally indicated by reference numeral  10 . The device  10  is suitable for being supported within an opening  12  formed in a tub wall  14  of a bathtub  16  for both filling the bathtub and providing an overflow drain  18  to the bathtub through the common opening  12  in the tub wall. 
   The device  10  includes a body having a first portion  20  to be mounted externally of the tub wall, and a second portion  22  projecting through the opening in the tub to be located internally within the tub in the mounted position. The first portion  20  includes an annular mounting face  24  extending about the body at the junction of the first and second portion so as to be oriented to face towards the second portion of the body. When the second portion extends through the opening in the tub, the annular mounting face  24  is arranged to overlap about a full periphery of the opening in the tub wall at the exterior side thereof. 
   The second portion  22  comprises a cylindrical threaded collar concentric with the annular mounting face  24  projecting coaxially therewith through the opening and beyond the tub wall into the interior of the bathtub. A mount includes a threaded mounting ring  26  which mounts about the threaded collar defining a second potion  22  and similarly includes an annular mounting face  28  which confronts the face  24  of the first portion far clamping the tub wall there between about the periphery of the opening. A suitable sealing ring  30  or sealing member of resilient material is supported between the mounting face  28  of the ring and the tub wall so that he mounting face  28  engages the sealing ring about the full periphery of the opening in the tub wall. 
   The collar defining the second portion  22  includes a hollow interior forming a drain inlet  32  at the second potion which communicates with a sleeve  33  forming a part of the first portion of the body. The sleeve is also hollow and defines a drain outlet  34  at an open bottom end thereof. The sleeve and the collar are substantially perpendicular with one another with the axis of the sleeve lying approximately at 93 degrees to the axis of the collar defining the second portion so that the drain outlet and the flow outlet are offset from perpendicular with one another within a range of 1 to 5 degrees. The collar and sleeve are enclosed at the point of communication with one another to define an enclosed drain passage extending from the opening at the drain inlet  32  of the collar to the opening in the sleeve defining the drain outlet  34 . 
   The body also includes a flow passage formed therein in the form of a tube  36  extending concentrically through the threaded collar defining the second portion. A flow outlet  38  of the flow passage extends coaxially through and beyond the collar defining the second portion although being smaller in diameter so as to define an annular space between the tube  36  and the surrounding collar which comprises the drain inlet. The flow inlet lies coaxially, so as to be parallel and concentric, with the flow outlet to extend through the opposing side of the body so that the flow inlet  40  projects through a rear face of the body at the first portion thereof. 
   The flow inlet is internally threaded for receiving a standard plumbing fitting therein. The threaded portion of the flow inlet  40  terminates at an internal shoulder where the flow passage increases in diameter for the remainder thereof towards the flow outlet. The diameter is suitable for slidably receiving a pair of check valves in series through the open end of the flow outlet  38  for abutment against the internal shoulder  42  of the flow passage. 
   An internal; annular groove  44  is formed adjacent the open end of the flow outlet for receiving a C-shaped retainer clip  46  therein which selectively retains the pair of check valves  48  within the flow passage. 
   Each of the check valves  48  is a self contained unit including a cylindrical housing, a valve head, a valve seat and biasing means for biasing the valve towards the closed position. The check valve only permits flow in one direction therethrough. 
   The check valves are supported within the flow passage so that both are oriented to only allow flow from the flow inlet to the flow outlet through the flow passage. In this configuration the two check valves  48  together form a back flow preventer or backflow prevention device in series with the flow passage. 
   A cap member  50  is provided to cover and conceal the flow outlet and drain inlet at the second portion of the body. The cap member includes a cylindrical body  52  having a hollow interior which is capped at an outer end  54  while remaining open at an opposing inner end  56 . A divider wall  58  spans the hollow interior to divide the cap member into a first chamber  60  adjacent the outer end  54  and a second chamber  62  adjacent the open inner end  56 . 
   A central aperture  64  in the divider wall  58  includes an integral mounting collar  66  supported thereon for receiving the end of the tube defining the flow outlet which projects beyond the collar forming the drain inlet  32 . An integral groove  68  formed within the collar  66  receives an O-ring therein for sealing between the flow outlet and the first chamber. The O-ring prevents any direct flow of fluid from the flow outlet and first chamber to the second chamber or the drain inlet within the interior of the cap member  50 . A set screw  70  holds the mounting collar  66  firmly in place in relation to the tube defining the flow outlet. 
   A plurality of spaced apart apertures  72  are provided in only the bottom portion of the cylindrical body  52  in communication with both the first and second chambers respectively. Flow from the flow outlet into the first chamber is thus even disbursed through the apertures  72  in the bottom of the chamber for dispensing into the bath tub. Similarly, rising water in the bathtub rises up through the bottom apertures in the second chamber for communication with the annular shaped drain inlet in communication through the open end of the cap member  50 . The backflow preventer formed by the check valves in series prevents the rising water from entering into the potable water supply fed to the flow passage. 
   The device  10  is installed within the opening  12  formed in a tub wall  14  typically for use with a conventional overflow device. The sleeve projecting downwardly from the device forming the drain outlet connects to a conventional plumbing tee  80  coupled to a drain line  82  of a drain  84  in the bottom of the bathtub. The tub filler line  86  coming from the mixer  88  of the hot and cold water supply lines is then connected to the rear face of the device at the flow inlet similar to connection to a conventional spout. 
   Periodically when the check valve forming the back flow prevention device requires servicing, the cap member is simply removed by loosening the set screw in the mounting collar thereof and the retainer clip at the flow outlet is then removed so that the check valves can be slidably removed through the flow outlet and replaced as desired. 
   While one embodiment of the present invention has been described in the foregoing, it is to be understood that other embodiments are possible within the scope of the invention. The invention is to be considered limited solely by the scope of the appended claims.

Summary:
A tub filler and overflow combination device is supported within a common opening formed in a tub wall. Both a flow passage and a drain passage extend through the body of the device to communicate through the common opening in the tub wall. A backflow preventer of the flow passage is slidably removable through the flow outlet for readily servicing the components of the backflow preventer as desired. The flow inlet is parallel and opposite to the flow outlet for ease of manufacturing and for ease of installation into a bathtub.