Water Drainage System

The current invention discloses a water drainage system designed for securing a waterproof membrane as well as centering a wastewater pipe. The water drainage system has a coupling mechanism including a lower drain body and a pipe-capturing member. The lower drain body may be installed in a substrate medium, such as a shower pan, onto which a waterproof membrane would be fixed. The pipe-capturing member has two frusto-conical designs which allow the pipe-capturing member to be firmly asserted into the lower drain body and at the same time center and secure the wastewater pipe. The pipe-capturing member and the lower drain body each has a flange wherein the two flanges trap and secure the waterproof member in place. Additional structures such as a drain trim holder may also be adopted to allow easier adjustment. The current invention is particularly useful for shower pan drainage.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments of the present invention will now be described with reference to the drawings. Identical elements in the various figures are identified, as far as possible, with the same reference numerals. Such embodiments are provided by way of explanation of the present invention, which is not intended to be limited thereto. In fact, those of ordinary skill in the art may appreciate upon reading the present specification and viewing the present drawings that various modifications and variations can be made thereto without deviating from the innovative concepts of the invention.

FIG. 1is a top perspective view of the water drainage system of the present invention fully assembled in a subfloor medium. Shown inFIG. 1is the substrate medium12into which the water drainage system is installed. The substrate medium12is shown in partially cut-away view for clarity purposes. Also shown inFIG. 1are a drain trim holder40and a drain plate18, the parts of a water drainage system of the current invention that is visible when it is assembled. The preferred embodiment of the current invention may generally be installed in substrate medium12at the location of a wastewater pipe. Also referring toFIG. 1, the substrate medium12is covered by waterproof membrane19, which is a novel design to overlay a surface onto which wastewater may be disposed. For example, the waterproof membrane may be used to cover the bathroom floor or bathtub.FIG. 1is the overview for water drainage system after installation is completed. The line between points A and B serves as an indicator for the sectional views of the water drainage system inFIGS. 3, and4.

FIG. 2is an exploded view of the water drainage system of the present invention.FIG. 3is an exploded sectional view of the water drainage system of the present invention, with the sectional line marked between points A and B inFIG. 1.FIG. 4is a sectional view of the water drainage system of the present invention when the water drainage system is fully assembled. As a group,FIGS. 2,3, and4demonstrate how the entire water drainage system would assemble and show essentially the same elements, including a drain plate18, a drain trim holder40, a pipe-capturing member15, a waterproof membrane19, a lower drain body14, and an anchoring nut32, with specific emphasis on different details of these element.

As shown inFIG. 2andFIG. 3, the water drainage system includes a lower drain body14encircling a receiving hole36. The lower drain body has a generally tubular, cylindrical section21wherein its lower part is threaded, defining a threaded section33. On top of the cylindrical section21, the lower drain body14has a lower drain flange28that expands annularly, and the lower drain flange28has a significantly larger diameter than the cylindrical section21. The lower drain body14also has a top surface31above the lower drain flange28, the top surface31pitching downward and inward radially towards the center of the receiving hole36, creating a sloped surface that may funnel water to flow through dedicated channels into a waste water pipe. Referring toFIG. 4, the top outer edge of the lower drain flange28should be substantially flush with the top surface of the subfloor medium12onto which a waterproof membrane19may be attached.

As shown inFIG. 2andFIG. 3, the water drainage system includes a pipe-capturing member15encircling a pipe hole35, the pipe-capturing member15having a tubular section22and a top flange20positioned on the tubular section22. The top flange20has an upper surface24and a lower surface27. Referring toFIG. 3, the lower surface27of the top flange20on the pipe-capturing member15has an annular pitch that matches the pitch of the top surface31of the lower drain body14, allowing flush contact between the lower surface27of the top flange20and the top surface31of the lower drain body14when the tubular section22of the pipe-capturing member15is inserted into the receiving hole36of the lower drain body14, if no membrane is separating the two structures.

One of the basic functions that may be served by the water drainage system is to provide draining for an area that is covered by a waterproof membrane19. As indicated above, the waterproof membrane19is a unique design for coverage of surfaces that may be susceptible to flow or accumulation of waste water. The pipe-capturing member15and the lower drain body15may serve as a coupling mechanism for the waterproof membrane19. As shown inFIG. 2andFIG. 3, the top flange20of the pipe-capturing member15has a pitched lower surface27that matches the pitched top surface31of the lower drain body14. The tubular section22of the pipe-capturing member15may be inserted through a hole37on the waterproof membrane19, and into the receiving hole36of the lower drain body14, wherein the hole37on the waterproof membrane19has a diameter similar to the exterior diameter of the tubular section22, thus trapping the waterproof membrane19underneath the top flange20and above the lower drain flange28. Since the lower surface27of the top flange20has matching pitch angles as the top surface31of the lower drain body14, the coupling of the pipe-capturing member15and the lower drain body14causes the trapped section25of the waterproof membrane19to pitch as shown inFIG. 2-4, allowing close contact between the components.

Referring toFIG. 3andFIG. 4, the exterior surface of the tubular section22of the pipe-capturing member15is tapered and decreases in diameter from the top, defined as the part closer to the top flange20, to bottom, making the exterior of the tubular section22a frusto-conical shape. Conversely, the interior diameter of the tubular section, which corresponds to the diameter of the pipe hole35, increases from top to bottom, making the pipe hole35a frusto-conical shape.

The tapering of the interior and exterior diameters of the tubular section21of the pipe-capturing member15is generally not very significant. The tapering angles for the interior and exterior diameters are between 0.1-5°, with the preferred tapering angle to be around 1°. Thus, due to the small tapering angle, the changes of the diameters are not dramatic.

Since the exterior diameter of the tubular section22of the pipe-capturing member15is tapered and decreases from top to bottom, it has a maximum exterior diameter positioned just beneath the top flange20. The maximum exterior diameter is substantially equal to the diameter of the receiving hole, which is substantially uniform. Referring toFIG. 3andFIG. 4, the tubular section22of the pipe-capturing member15may be inserted into the receiving hole36of the lower drain body14from the top. Since the exterior diameter on the lower part of the tubular section22is smaller than the diameter of the receiving hole36, the insertion is made easier. Moreover, the tapered exterior surface of the tubular section22permits application of a chemical bonding adhesive between the tubular section22and the interior of the lower drain body14without causing squeezing away of the adhesive when the tubular section22is being inserted into the receiving hole36.

Since the interior diameter of the tubular section22of the pipe-capturing member15is tapered and increases from top to bottom, it has a minimum interior diameter positioned just beneath the top flange20. The minimum exterior diameter is preferred to be substantially equal to the generally uniform outside diameter of a wastewater pipe, which is to be inserted into the pipe hole35from the bottom. The tapered interior surface of the tubular section22makes the insertion of a wastewater pipe easier. Moreover, the tapered interior surface of the tubular section22permits application of a chemical bonding adhesive without causing squeezing away of the adhesive when the wastewater pipe is inserted into the pipe hole35of the pipe-capturing member.

As shown inFIG. 3, the top flange22of the pipe-capturing member has an upper interior edge29, the upper interior edge29is shaped as a chamfer that extends radially, forming a funnel shape. Such a design facilitates the flowing of wastewater into the wastewater pipe, which is inserted into the pipe hole35of the pipe-capturing member15.

Referring toFIGS. 2,3and4, the pipe-capturing member15has weeping holes17though the body of the pipe-capturing member15. Each of the weeping holes17has one opening just beneath the top flange22, with another opening on the chamfer of the interior edge29. The weeping holes17are positioned at an angle to facilitate draining into the pipe hole35and the wastewater pipe in the pipe hole35. As shown inFIG. 4, the diameter of the top flange22is preferably smaller than the diameter of the lower drain flange28, making the waterproof membrane19to taper at location34, which is also shown inFIGS. 2 and 3. The tapering of the waterproof membrane19at location34creates a pocket, which may facilitate the flowing of wastewater to the water drainage system. Most of the waste water may make its way above the pipe capturing member15, over the chamfer29and into the wastewater pipe. Even if there is any wastewater flowing under the top flange20, it will still escape through the weeping holes17and into the wastewater pipe.

As shown inFIGS. 2,3and4, the water drainage system may further comprises an anchoring nut32, which has a threaded interior that may be fastened to the threaded section33of cylindrical section21of the lower drain body14. Referring toFIG. 4, the anchoring nut32may be placed beneath the substrate medium12, creating further stabilization to the water drainage system, making it more difficult to dislocate the lower drain body14, the pipe-capturing member15, and other components of the water drainage system. However, it should be noted that the lower drain body14may be connected to the anchoring nut32with other approaches, such as but not limited to: co-molding and gluing. The anchoring nut32may also be entirely left out if the water drainage system is sufficiently secured.

As shown inFIGS. 2,3and4, the water drainage system may further include a drain trim holder40, which may be positioned on top of the pipe-capturing membrane15. The drain trim holder40may have different designs according to specific needs. In the embodiment shown inFIGS. 2-4, the exterior wall41of the drain trim holder40has a saw tooth design and the interior wall43of the drain trim holder40has a square tooth design. These designs allow the height of the drain trim holder40to be adjusted depending on the thickness of the material to be used on the finished floor, into which the water drainage system is installed. Referring specifically toFIG. 3, a bottom wall45of the drain trim holder40is sloped towards the center to create a funnel shape to ensure that the waste water that enters the drain trim holder will flow to the waste water pipe. There is a drain hole44on the bottom wall45of the drain trim holder40. The diameter of the drain hole44is substantially equal to the diameter of the waste water pipe that is to be inserted into the water drainage system. Upon installation, the drain hole44, the pipe hole35, and the receiving hole36are aligned to create a channel for wastewater collection and outflow.

As shown inFIGS. 2-4, the water drainage system may also include a drain plate18and mounting screws16. The drain plate18may be used to cover the drain trim holder40. The drain plate18has multiple openings through its body, allowing flow of water into the water drainage system. The drain plate18may be pressure fit into the drain trim holder40after the drain trim holder40has been cut or lifted to the appropriate height of the finishing surface. The mounting screws16may attach the drain plate holder40to the pipe-capturing member15. As shown inFIG. 3andFIG. 4, there are adjustment holes42in the drain trim holder40and vertical screw holes26in the pipe-capturing member15. The diameter of the adjustment holes42are significantly larger than the diameter of the mounting screws16so that the position of drain trim holder40may be adjusted for the ideal location of the drain trim plate. From a top view, the drain plate18and the drain trim holder40may be a square shape. Upon installation, the drain trim plate18is fit into the top of the square drain trim holder40which is secured with the mounting screws16to pipe-capturing member15.

As indicated above, it is preferred that the tubular section22of the pipe-capturing member15is inserted into the receiving hole36of the lower drain body. It is also preferred that the lower drain body14and the pipe capturing member15are attached with adhesives. Similarly, a wastewater pipe may be inserted into the interior of the pipe-capturing member15and attached to the pipe-capturing member15with adhesives. It should also be noted that adhesives may not be the only approach to join the three structures. For example, sonic-welding, as well as other methods, may also be utilized as long as effective attachment may be obtained.

In terms of materials, the various components of the water drainage system may be made from same or different materials. It is desirable that the materials are waterproof, durable, robust, easy to mold, and relatively inexpensive. The materials that may be used include but are not limited to: metal, rubber, and plastic such as, but not limited to, polyethylene terephthalate (PET), polyethylene (PE), high-density polyethylene, polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), high impact polystyrene (HIPS) and polycarbonate (PC), or some combination thereof. The preferred material for making the lower drain body14and the pipe-capturing member is PVC.

FIGS. 5A-H provide a full illustration of the pipe-capturing member15, whereinFIG. 5Ais a top perspective view,FIG. 5Bis a top view,FIG. 5Cis a bottom view,FIG. 5Dis a front view,FIG. 5Eis a back view,FIG. 5Fis a first side view,FIG. 5Gis a second side view,FIG. 5His a sectional side view.

FIGS. 6A-H provide a full illustration of the lower drain body14, whereinFIG. 6Ais a top perspective view,FIG. 6Bis a top view,FIG. 6Cis a bottom view,FIG. 6Dis a front view,FIG. 6Eis a back view,FIG. 6Fis a first side view,FIG. 6Gis a second side view, andFIG. 6His a sectional side view.

FIG. 7is an exploded sectional view of an alternative embodiment of the water drainage system of the present invention. The embodiment shown inFIG. 7shares significant similarities with the embodiment shown inFIGS. 1-6. In addition, this embodiment provides certain features that are in some aspects more advantageous.

Shown inFIG. 7are a drain plate18, a drain trim holder51having a stepped inner flange53, an inner connecting member70, a first busing54, a second bushing57, an outer capturing member60, a waterproof membrane19, a lower drain body14, an adaptor80, and an anchoring nut32. Here, the structures some components, such as the anchoring nut32and the drain plate18, are similar to the same elements shown inFIGS. 2,3, and4.

The lower drain body14encircles a receiving hole36having a generally uniform first diameter, a top part of the lower drain body14being a lower drain flange28that extends radially outwardly, the lower drain flange28having an upper surface sloped to the center of the receiving hole36, the lower drain body14further having a cylindrical section21below the lower drain flange28.

The outer capturing member60has an outer capturing member tubular section64encircling an outer capturing member hole66and an outer capturing member top flange63that extends radially outward. The tubular section64of the outer capturing member60has an exterior diameter and an interior diameter. The outer capturing member top flange63is positioned on top of the tubular section64and has a sloped lower surface. The sloped lower surface of the outer capturing member top flange63is substantially parallel to the upper surface of the lower drain flange28. The tubular section64of the outer capturing member60may be inserted into the receiving hole36of the lower drain body14. The outer capturing member top flange63and the lower drain flange36of the lower drain body14hold flush and secure the waterproof membrane19, which covers a substrate medium. Different from the embodiment shown inFIG. 2-4, here the tubular section64of the outer capturing member60extends below a lower end of the lower drain body14. The lower part of the outer capturing member tubular section64is threaded. The adapter80and the anchoring nut32may be attached to the threaded part of the outer capturing member tubular section64, with the anchoring nut32preferably screwed to the threaded part.

The inner connecting member70has an inner connecting member tubular section71encircling an inner connecting member hole75and an inner connecting member top flange72that extends radially outward. The inner connecting member tubular section71may be inserted through the drain trim holder51so that the inner connecting member top flange72rests on the stepped inner flange53of the drain trim holder32. The inner diameter of the hole in the drain trim holder51is modestly larger than the exterior diameter of the inner connecting member tubular section71, with a difference preferably ranges between 2 to 50 mm. With this feature, the inner connecting member70allows the drain trim holder51to be modestly repositioned when the inner connecting member70is inserted through the drain trim holder51. Such a feature may reduce work load to avoid tile cutting, if tiles are used. Similar to the weeping holes shown inFIGS. 2-4, there may also be weeping holes17through the inner connecting member tubular section72, wherein the weeping hole17may be used for the drainage of residue water.

The first bushing54and the second bushing57are inserted into the outer capturing member hole66, with the first bushing54being positioned above the second bushing57. The first bushing54and second bushing57are made from flexible and waterproof materials such as rubber. In addition, the first bushing54and the second bushing57have circling protrusions that ensure capturing. The inner connecting member tubular section71may be inserted into the first bushing54and being secured by the first bushing54. A pipe may extend through the second bushing57. capturing member, the weeping holes having openings on the radial chamfer of the upper interior edge of the pipe-capturing member and having an angle to facilitate draining into the pipe hole, and the integral weeping holes in the pipe-capturing member are substantially parallel to the top surface of the upper flange of the pipe capturing member.

The water drainage system may also include other structures to form a more comprehensive and complete design for improvement of a household drainage assembly. For example, the water drainage system may include a shower pan that may be combined with the pipe centering and membrane securing mechanisms such as the lower drain body14and the pipe-capturing member15(FIG. 3) or the lower drain body14and the outer capturing member60(FIG. 7). The shower pan is installed over a subfloor or an underlayment that in most cases comprises plywood or other support structures.

On key component of the shower pan is the substrate medium12as shown inFIGS. 1 and 4. The substrate medium is made from durable and water-resist materials such as but not limited to: metal, rubber, and plastic such as, but not limited to, polyethylene terephthalate (PET), expanded polystyrene (EPS), polyethylene (PE), high-density polyethylene, polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), high impact polystyrene (HIPS) and polycarbonate (PC), or some combination thereof. The preferred material for the substrate medium12is EPS. The substrate medium is molded to have a slightly sloped surface, wherein the lowest point in the shower pan coincides with the location of the inlet of the wastewater pipe. A waterproof membrane19covers the substrate medium12as shown inFIGS. 1 and 4, providing a separating layer between the substrate medium12and water flow. The waterproof membrane19is preferred to be self adhesive. However, other methods may be used to attach the waterproof membrane19to the substrate medium12. The waterproof membrane19has the same features.

The shower pan may also include a curb completely or partially surrounding the substrate medium. The curb may be made from the materials identified above or plastic wood composite. It is desirable that the curb be made from water resistant materials. The curb is thicker than the substrate medium and as a combined structure the curb and the substrate medium define the contours of the shower pan. It is preferable that the waterproof membrane also covers the curb. In addition, the waterproof membrane may expand upward against the splash wall adjacent to which the shower pan is installed, providing an extensive waterproof surface.

The waterproof membrane may be folded or cut to match the surfaces of the shower pan and the splash wall. The preferred method is to fold the membrane because such an approach does not leave gaps that may cause accumulation of moisture on the inner surfaces and in the inner voids. The splash wall, which may also be considered a part of the water drainage system, may provide the space needed for disposing the fold-up portion of the waterproof membrane that is not used to provide cover to the water drainage system. The splash wall may have a splash wall void behind it or between sub-layers of the splash wall. There are multiple ways to fold the waterproof membrane. The fold-up portion of the waterproof membrane may be folded into the splash wall void, keeping the appearance of the shower pan clean and neat, also preventing necessary cutting of the waterproof membrane.