CA2644553A1 - A slide-on groove and flange faceplate-tieplate overflow sub-assembly of a sink or bath drain assembly - Google Patents

Abstract

An overflow sub-assembly consists of an overflow faceplate that slides over and down the overflow tieplate by means of a internal slot mating with a matching flange on the tieplate. This invention requires no fasteners to attach the faceplate to the tieplate, leaving the faceplate free to bear a variety of finishes, including in-mould decorating, conventional plating, mirror finish, texture, and three-dimensional ornament.

Description

Background of the Invention A bath or sink, herein "vessel", is drained by a "waste-overflow" bath drain assembly. The upper portion of this assembly consists of an "elbow", sometimes called a "head fitting", that is fastened to the vessel wall by a "tieplate"
fastened by a variety of means through the overflow hole in the vessel wall into the elbow on the outer vessel wall. In this Application, this tieplate is annular in shape, with a flat flange hugging to the inner side of the vessel. The internal circumference of this annular flange bears an externally or male threaded short pipe which passes through the overflow hole, through a water seal gasket, and then threads into an internal or female thread within the elbow. Other tieplate shapes include a simple tiebar across the width of the overflow hole, and round plates with bolt holes.

In the early days of plumbed baths, a perforated metal plate was fastened to this tieplate by means of a bolt which might also bear a chain suspending a plug.
This fastened plate was called a "faceplate". This terminology stuck even when the faceplate was deepened into a cup, the perforations moving off the vertical face plane to the bottom of the cup rim, out of aesthetic sight. Ball (US
5,890,241: April 6, 1999) is an example of a bolt-on faceplate.

Other means of securing the faceplate to the tieplate include snap-on faceplates (Dunnett US 7,007,319: March 7, 2006), hinged faceplates (Freville US
4,796,310: Jan 10, 1989), and faceplates secured with a set screw (Ball US

6,173,459: Jan. 16, 2001). Often the attachment is integral to some more complex drain functionality, as in all of the above patents.

Although no patents exist employing a slide-on utility for hanging the faceplate onto the tieplate, reference to somewhat similar slide-on functions in other utility classifications taking advantage of a mating slot and tab can be found in Mcllvenna (US 6,669,492: December 30, 2003) and In (US 7,094,969: August 22, 2006). In this Application, the slot is interior and rear to the faceplate, and the tab a mating flange on the tieplate running concentrically and circumferentially on the main flange, with sufficient clearance from the vessel wall to allow the grooved faceplate to fit over this mating flange of the tieplate.

Covering the overflow hole with a faceplate performs mainly an aesthetic function.
Indeed, an open overflow without a faceplate would provide the best functionality for the drainage functions of the overflow hole; namely, (1) The overflow hole serves as a pressure relief vent when the water drains out of the waste drain in the bottom of the vessel. This avoids having the water being siphoned out of the water trap that is plumbed between the vessel drain and the pipe to the primary sanitary drain. Maintenance of water in this water trap is essential for preventing sewer gases from travelling upward into the vessel.

(2) The overflow hole mitigates overflowing of liquid over the brim of the vessel, hence its name.

(3) The overflow hole provides access to the household drain system as it permits the passing of a "snake" by the plumber to clear blockages. In general, contemporary tieplates and tiebars that fasten the rear elbow to the bath have (or consist of) a cross bar to which the faceplate is fastened.
This prevents plumber snake access. Temporarily unscrewing the faceplate is not an option as the elbow would fall off behind the vessel.

Nonetheless, in most vessel installations the user of the vessel has come to expect that the overflow hole be discretely covered by a faceplate, though even frontal perforations became unacceptable, leading to the evolution of the cup shaped faceplate with perforations on the rim underneath.

As part of the evolution of the overflow assembly, this Application describes a novel faceplate-tieplate sub-assembly wherein the faceplate is designed to slide over and onto the tieplate. Although simple, this subassembly enables all three of the drainage functionalities to be realized; namely, 1) Retention of functionality as an air relief vent.

2) Retention of liquid overflow mitigation functionality.
3) Preservation of snake access.

Additionally, using a slide-on faceplate brings the following benefits.

4) No fastener is required to attach the faceplate to the tieplate.

5) Indentations can be moulded around the inner circumference of the tieplate to capture the chain ball and suspend a chain and plug for the vessel waste drain, meaning the faceplate can be removed without disturbing the chain, if a chain and plug are indeed selected as to be the waste drain closure.

6) The faceplate is free to be shaped, patterned, or designed in any manner, no longer having a screw hole through its center or needing to accommodate snap features or hinges.

Brief Summary of the Invention This application describes a novel faceplate-tieplate sub-assembly wherein the faceplate is designed to slide over and onto the tieplate of a sink or bath drain assembly by means of a slot fitting over a mating flange. This sub-assembly covers the overflow hole of the vessel. Although simple, this sub-assembly enables all three of the overflow drainage functionalities to be realized;
namely, 1) Retention of functionality as an air relief vent.
2) Retention of liquid overflow mitigation.

3) Preservation of snake access to clear blockages in the drain.
Additionally, using a slide-on faceplate brings the following benefits.
4) No fastener is required to attach the faceplate to the tieplate.

5) Indentations can be moulded around the inner circumference of the tieplate to capture the chain ball and suspend a chain and plug for the vessel waste drain, meaning the faceplate can be removed without disturbing the chain, if a chain and plug are indeed selected as to be the waste drain closure.

6) The faceplate is free to be shaped, patterned, or designed in any manner, no longer having a screw hole through its center or needing to accommodate snap features nor hinges.

Detailed Description of the Invention The waste-overflow sub-assembly of a vessel drain assembly has an "elbow", also known as "head fitting", behind the bath or sink vessel, centered upon the overflow hole in the vessel wall. Between the vessel wall and the elbow is a gasket that prevents leakage of vessel liquid. In order to cinch this elbow and its sandwiched seal tight against the vessel wall, a part called the "tieplate"
must be positioned on the opposite, interior, side of the vessel wall, again centered on the overflow hole. Any number of means is used to pull the the elbow tight to the part on the interior of the vessel, called the "faceplate". Bolts are most common.
In this Application an annular faceplate with a male-threaded short pipe running from inner diameter of this ring is chosen, this male thread fitting into the female thread of the interior of the elbow chosen for this Application. This architecture allows for an aesthetic cover plate-tieplate sub-assembly as in Fig. 1. The tieplate (2) flange bears a thinner mating flange (6) that is of a diameter such that the fitted slot (5) in the rear interior of the faceplate (1) fits over and down on the mating flange to rest with the semi-circular slot portion sitting on top of the semi-circular region of the tie-plate mating flange that is orientated topmost. The male-threaded pipe of the annular tieplate inserts into the vessel wall (4) via the overflow hole (3) in that same vessel wall.

Fig. 2 illustrates once again how the slot or groove (5) in the faceplate (1) fits over the tieplate mating flange (6) by means of a gap (7) on the underside of the faceplate. This enables the following functionalities:

1) No fastener necessary to attach the faceplate to the tieplate.

2) No horizontal member necessary to accept these fasteners, so the center of the tieplate (Fig. 1 (3)) can remain empty and allow for the passage of a plumber's snake.

The gap also performs two traditional functions of a faceplate:
1) Allows air pressure venting.

2) Allows for mitigation of the liquid overflow.

This very simple method of attaching a cosmetic faceplate to a tieplate is novel both in what it lacks, that is, a fastener and a central bar on the tieplate, as for what it gains, that is, a fitted slot-flange coupling and a smooth faceplate surface opportunity for decoration. Although the faceplate in the two Figures is rounded at the top, any shape would be possible, including rectangular. Functionality can be optionally added to the interior region of the sub-assembly, for example, indentations to capture the ball of a chain and plug drain stopper.

Claims (3)

1) In this Invention, an overflow faceplate slides over and down the overflow tieplate by means of a fitted slot mating with a matching flange to form a sub-assembly of the vessel drain assembly.

2) This Invention requires no fasteners to attach the faceplate to the tieplate.

3) The faceplate can bear a variety of finishes, including in-mould decorating, conventional plating, mirror finish, texture, and three-dimensional ornament.