A Toilet That Catches Debris Before It Clogs An In Line Strainer for Institutional Plumbing

This application is about a very specific and very expensive failure: the moment a stainless steel institutional toilet stops flushing properly because bits of perished rubber from upstream valve gear have lodged in its jet. Claim 1 covers a toilet fixture with an inlet pipe, a bowl, an outlet pipe, a jet pipe joining the inlet to the outlet, and a foreign object strainer positioned in line with the inlet pipe so the debris never reaches the fixture at all. A second independent claim applies the same strainer to the flush assembly behind the wall. The applicant is SDB IP Holdings, LLC, the United States patent holding entity associated with the founder of I-CON Systems, a Florida maker of plumbing controls and fixtures for correctional facilities.

The Problem

The specification’s description of the prior art reads like a maintenance log. In current toilet fixtures, it says, angle stop sealing material, flush valve diaphragms and vacuum breaker rubber all have a tendency to deteriorate over time, which causes those elements to break apart and flow into the piping system of the fixture. None of these components is part of the toilet. They sit upstream of it, in the valve gear that meters the flush, and when they fail they send their own fragments downstream.

That debris, together with general dirt already in the pipework, causes blockages beyond the water closet’s inlet, specifically in the blowout jet or in the flush rim holes that rinse the bowl. The consequence the specification records is the obvious one: poor flushing and poor removal of waste. In a domestic bathroom that is an annoyance. In the environments this fixture is built for it is a sanitation and security problem, and the fixture cannot simply be swapped out on a Tuesday afternoon.

Then comes the part that explains why this application exists at all. Removing debris from a blowout jet, the specification says, is particularly difficult when the jet is welded into the waste pipe. Doing so requires the fixture to be taken off the wall and shipped back to the manufacturer, where it is cut apart, re welded and returned to the customer for reinstallation. The alternative that others have tried is described with a wince: pulling the fixture off the wall, turning it upside down, heating the blowout jet area with a torch to melt the debris, and hammering on the jet while doing so.

The summary sets out three needs in sequence, and the sequence is the design. There is a need for a fixture with a clog prevention and cleanout assembly. There is a further need for a fixture that can stop debris entering the bowl in the first place. And there is a further need for a fixture that allows easy cleanout of debris in the event that some gets through anyway. Prevention first, then recovery.

What This Invention Does

Claim 1 is short by the standards of this batch. A toilet fixture comprising an inlet pipe; a toilet bowl in fluid communication with the inlet pipe; an outlet pipe in fluid communication with the bowl; a jet pipe in fluid communication with both the inlet pipe and the outlet pipe; and a foreign object strainer positioned in line with the inlet pipe. That is the whole of it. The novelty being asserted is the interception point, upstream of the bowl and upstream of the jet, rather than any change to the bowl itself.

The description fills in what the strainer actually is. It has a tubular main body that threads onto the inlet pipe at one end and connects to the fixture’s fitting ring at the other, so it drops into the existing run of pipe. Inside the main body sits a strainer plate set at an angle to the longitudinal axis of the passageway, with apertures sized to let water through and stop larger debris. Below the body a threaded extension holds a removable reservoir, and a cover threads onto the extension to hold the reservoir in place.

The angle is the working part. Because the plate is tilted, water passes through the apertures while blocked debris slides down the face of the plate and falls into the reservoir underneath rather than sitting on the plate and slowly choking it. Servicing is then a matter of unthreading the cover, lifting out the reservoir, tipping out the debris and putting it back. That is the whole maintenance procedure, and it replaces cutting the fixture apart.

Claim 8 is a second independent claim covering the flush assembly rather than the fixture: a flush valve, a vacuum breaker tube in fluid communication with the flush valve, a foreign object strainer in fluid communication with the vacuum breaker tube, and an outlet pipe in fluid communication with the strainer. The same strainer, in other words, placed inside the concealed valve gear behind the wall. In the worked example the flush assembly runs from a momentum flush valve through a vacuum breaker pipe and an elbow joint into the strainer, and out to the fixture’s inlet.

The description adds options that never make it into the claims but say a good deal about the intended installation. The strainer can carry an overflow detection aperture, optionally fitted with a through beam sensor that signals a controller when debris interrupts it, or with a pressure sensor that reports the pressure rise a blockage causes. The cover can simply be made of clear material so a technician can look in. There is also a combined vacuum breaker and mesh strainer, the breaker moulded from EPDM rubber and the mesh from stainless steel.

Key Features

• Interception before the fixture. The strainer sits in line with the inlet pipe upstream of the bowl, so debris shed by upstream valve components is stopped before it can reach the flush rim holes or the blowout jet where it causes the blockage.
• Angled strainer plate. The plate is set at an angle inside the main body rather than square across it, so water passes through the apertures while blocked debris is directed down the face and away instead of accumulating on the screen.
• Emptiable reservoir. A receptacle beneath the plate collects what the plate stops, and a threaded cover releases it so the reservoir can be pulled out, emptied and reinstalled without disturbing the fixture or the pipework.
• Apertures sized to the job. The specification is explicit that the number and dimensions of the apertures are chosen for each fixture based on the size of foreign object expected to move through it, which makes the plate a tuned component rather than a generic screen.
• A cleanout hole at the jet fitting. A fitting in line with the inlet pipe and connected to the jet pipe carries a capped cleanout hole giving direct access to the interior of both pipes, which is the recovery half of the design for debris that gets past the strainer.
• A parallel claim for the concealed valve gear. Claim 8 covers the flush assembly on its own, putting the strainer between the vacuum breaker tube and the outlet, so the same protection can be fitted behind the wall on installations where the fixture itself is not being replaced.

Who Is Behind It

SDB IP Holdings, LLC is a patent holding company rather than a trading business. The public patent record ties it to Shawn D. Bush, whose earlier flush valve patents were assigned first to I-CON Systems, Inc. and later to SDB IP Holdings, and whose initials the entity name reproduces. Bush founded I-CON in 1994 in Oviedo, Florida, and the company designs, manufactures and installs plumbing control systems for the corrections market.

That connection makes the specification much easier to read. In a January 2024 interview with Correctional News, Bush named three problems the company works on, and the second is the one this application addresses word for word: clogging in the water flush jet, which can render the toilet useless, answered by removable jets that simplify cleaning of debris and eliminate the need to remove the entire toilet and send it out for repair. The MOMENTUM branded flush valve he describes in the same interview is the momentum flush valve that appears as a numbered component in this specification’s flush assembly example. In January 2025, after this family was filed, Watts Water Technologies acquired I-CON Systems for its corrections plumbing business, which the buyer put at roughly twenty five million dollars of annualised sales.

One inventor is named, Christopher Harrison. The specification says nothing about him beyond the name.

The priority chain is stated in full in the first paragraph of the body text and is the longest of this batch. AU 2026202146 is a divisional of Australian patent application 2020361592, which the specification records as filed 23 March 2022 and as the national phase of PCT application PCT/US2020/054954 filed 9 October 2020, which in turn claims priority from United States provisional application 62/913,233 filed 10 October 2019. The priority country is therefore the United States, with an earliest asserted date in October 2019. The published pages of the body still carry the running headers of the international publication the text was taken from, which is a reasonable reminder that the disclosure here is five and a half years older than the Australian filing date.

A second quirk is worth noting. The title page abstract leads with a removable jet pipe assembly that connects the jet pipe to the outlet pipe, and the description develops that assembly at length, complete with a mounting base, spring loaded locking arms and an adjustment screw for the spring force. None of it is claimed in this divisional. The fourteen claims here cover the foreign object strainer and the flush assembly only, which is exactly what a divisional is for: the removable jet sits in a different member of the family.

Why It Matters

Institutional plumbing is a genuinely distinct engineering discipline and it rarely gets written about. A fixture destined for a prison, a police lock up or a behavioural health unit has to be vandal resistant, fastened so it cannot be dismantled from the occupied side, and welded from stainless steel rather than cast in vitreous china. Every one of those requirements makes it harder to service. The welded blowout jet the specification complains about is not a design oversight, it is the direct consequence of a fixture built to survive deliberate attack, and cutting the fixture apart to clear it is the honest price of that decision.

Seen in that light the invention is less a plumbing improvement than a maintenance economics one. The cost being attacked is not the strainer, which is trivial. It is the cell taken out of service, the technicians, the wall opened up, the fixture freighted to a factory and back. Moving the failure point to a threaded cartridge that a maintenance officer can empty in a corridor changes a multi week works order into a routine round.

There is a water angle too, and it is the reason a company that sells electronic flush controls cares about debris in the first place. A partially blocked jet does not stop the toilet, it degrades it, and a degraded flush gets used twice. Across thousands of cells, the difference between a clean jet and a fouled one shows up directly in consumption, which is the metric the whole product line is sold on.

The unclaimed sensor options are a signal about where fixtures of this kind are heading. A detector across a debris reservoir turns a passive strainer into something that tells the facility it needs emptying before anyone notices a bad flush. The claims do not reach that far, but the disclosure makes it plain that somebody was thinking about it.

Related Concepts

• Flushometer – the tank free flush valve class that the momentum valve in this specification’s flush assembly belongs to.
• Backflow – the contamination risk that the vacuum breaker in the claimed flush assembly exists to prevent.
• Sieve – the general principle of the angled apertured plate that separates debris from the flush water.
• Prison cell – the installation environment that drives the welded stainless steel construction this design has to work around.
• Preventive maintenance – the servicing model the emptiable reservoir is designed to make possible.

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AU 2026202146 was published in the Australian Official Journal of Patents on 9 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.