Summary of the Invention
The present invention relates to flush valves or flushometers for use with plumbing fixtures such as water closets and urinals and has particular application to the inlet and outlet connections therefor.
One purpose of the present invention is an improved connection between the outlet of a flush valve and a flush tube which is simple in construction and reliable.
Another purpose is a plumbing connection of the type described which remains tight and leakproof over a long period of time, even with the intermittent application of water pressure occasioned during normal use.
Another purpose is a plumbing connection of the type described utilizing a clip ring which is urged into surface penetration with the flush tube as the fitting is tightened, with distortion of the sealing gasket providing the energy required to force the clip ring into such engagement.
Another purpose is a plumbing connection of the type described in which the sealing gasket is distorted into contact with multiple elements and which sealing gasket, due to the distortion force applied during assembly of the connection, causes the clip ring to penetrate the exterior surface of the flush tube to anchor the connection upon the flush tube.
Another purpose is an improved plumbing connection between a plumbing fitting, such as a flush valve, and a tube or pipe used as a part of a flush valve installation.
Other purposes will appear in the ensuing specification, drawings and claims.
Brief Description of the Drawings
The invention is illustrated diagrammatically in the following drawings wherein:
FIG. 1 is a side view of a flush valve illustrating the connection between the flush valve outlet fitting and the flush tube,
FIG. 2 is an enlarged section illustrating the connection between the flush valve outlet fitting and the flush tube, and
FIG. 3 is a side view, similar to FIG. 2, showing the connection in the loaded or tightened position.
Description of the Preferred Embodiment
The present application is concerned with the connection between the outlet of a flush valve or flushometer, as it is currently termed, and the flush tube which connects the flush valve to a plumbing fixture such as a water closet or urinal. The invention also has application to other fitting/tube connections in a flush valve installation such as between the flush valve inlet and the control valve and between the vacuum breaker and relating plumbing fittings. It is essential that such connections be watertight and that they remain watertight over a long period of time, particularly when the connection is made behind the wall of the washroom where it is not visible or readily accessible for repair.
Whenever a flush valve is operated, there is a sudden surge of water through the flush tube and related pipes that connect with the plumbing fixture and unless the connections are firmly anchored, they will in time work loose. At present, one common way to anchor the flush tube to the flush valve is to score the exterior surface of the flush tube in the area where the connection will be made so that the sealing gasket can itself anchor to the flush tube. In practice, this has not proved to be totally satisfactory.
The connection of the present invention will be described in relation to the flush valve outlet and the flush tube, although it should be understood that the same arrangement of parts could be used elsewhere in a flush valve installation. A split ring or clip ring is utilized to anchor the flush tube to the flush valve and this ring is driven into surface penetration with the flush tube as the sealing gasket is compressed and distorted when the connection is assembled. The invention will be described in connection with flush valves of the type manufactured by Sloan Valve Company of Franklin Park, Il., but the invention has application to any type of flush valve in which there is a required connection between the valve and the flush tube which leads to the toilet fixture.
In FIG. 1, a typical flush valve of the type manufactured by Sloan Valve Company is illustrated generally at 10, with the interior mechanism of the flush valve not being illustrated, as such is well known in the art, and may be found, for example, in U.S. Pat. No. 4,327,891. The handle for operating the flush valve is indicated at 12 and the outlet is indicated at 14. The outlet which is termed the "fitting" has an exterior threaded area 16 (FIGS. 2 and 3). A flush tube 18 is positioned within outlet fitting 14, with the flush tube conventionally having its opposite end connected to a plumbing fixture such as a water closet or urinal.
As illustrated in more detail in FIGS. 2 and 3, and looking first at the unloaded or untightened position of the connection in FIG. 2, there is a coupling nut 20 which has an inwardly-directed annular shoulder 22 at the end away from the fitting and has an interiorly threaded area 24 which is formed and adapted to mate with the threaded area 16 on outlet fitting 14. Thus, the coupling nut is used to make the connection between the outlet of the flush valve and the flush tube.
When nut 20 is assembled onto fitting 14 the two elements define a chamber which circumferentially extends about the flush tube and is indicated generally at 26. Positioned within chamber 26 is an elastomeric or rubber sealing gasket 28 which is in contact with end surface 30 of fitting 14. Adjacent gasket 28 is a back-up ring 32 which may be metal or plastic, but is rigid in contrast to the distortable material of the gasket. Back-up ring 32 has an annular groove 34 at the interior surface thereof on one side and a similar annular groove 36 at the interior surface thereof on the opposite side. Adjacent back-up ring 32 is a clip ring 38 which is used to attach or secure the flush tube to the fitting. Ring 38 may be of spring steel and conventionally will be a split ring for ease in assembly onto the flush tube. A split ring is also advantageous in that it requires less force to penetrate the flush tube. The interior surface of annular shoulder 22 of coupling nut 20 may have a groove 40 which is similar to grooves 34 and 36 on the interior surface of back-up ring 32.
FIG. 2 illustrates the connection prior to tightening coupling nut 20. All of the elements are illustrated in their free undistorted and untightened position. FIG. 3 illustrates the connection after it has been fully tightened. As coupling nut 20 is advanced onto the threads of fitting 14, rubber gasket 28 will be distorted as the size of chamber 26 decreases. This distortion will provide movement of the back-up ring toward clip ring 38 with the result that the clip ring will pivot about edge 42 formed by groove 34 so that the inner edge or surface of the clip ring, indicated at 44, will be driven into biting engagement or into surface penetration with the exterior of the flush tube. The energy or force which causes the clip ring to penetrate the surface of the flush tube is provided by the distorting rubber gasket as such distortion is brought about by a decrease in size of chamber 26. The back-up ring is driven into the clip ring and the rubber gasket distorts not only into groove 36 of the back-up ring, but into the threads of the coupling nut. The rubber gasket will firmly engage and seal with the exterior of the flush tube and will tend to move into any area which is open and directly adjacent the gasket as it is distorted by assembly of the coupling nut. When the connection is fully made, the gasket will be in sealing engagement with end 30 of the fitting, threads 24 of the coupling nut, one side of and groove 36 of the back-up ring and the exterior of the flush tube. The seal is complete and the connection is anchored onto the exterior of the flush tube as edge 44 of clip ring 38 will have been driven into surface penetration with the flush tube.
As it is possible in any assembled connection of this type for the clip ring to be put in backwards, groove 40, similar to groove 34 on the back-up ring, also defines a pivot point for the clip ring. Thus, if ring 38 should be assembled backwards, the ring will pivot about the edge defined by groove 40 of shoulder 22 and the back-up ring as the coupling nut is tightened onto the fitting. The connection will be the same in either case, as what is required is a means to urge the clip ring into penetration with the surface of the flush tube, under force provided by the distorting rubber of the gasket.
The connection is particularly advantageous in that it is simple, foolproof in terms of assembly, and reliable. The flush tube is anchored by clip ring 38 to the fitting of flush valve and this connection will remain through years of service.
U.S. Pat. No. 3,273,919 shows a similar connection between the flush valve inlet and a control valve.
Whereas the preferred form of the invention has been shown and described herein, it should be realized that there may be many modifications, substitutions and alterations thereto.