AU725463B2 - Toilet improvements - Google Patents

Description

47201 HKS:LJF P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

S

Name of Applicant: RONALD JAMES FLAHERTY AND ERNEST HENRY CAMBRIDGE Name of inventor(s): RONALD JAMES FLAHERTY AND ERNEST HENRY CAMBRIDGE Address for Service: COLLISON C0.,117 King William Street, Adelaide, S.A. 5000 Invention Title: TOILET IMPROVEMENTS Details of Associated Provisional Application: PO5000 dated 6th February 1997 The following statement is a full description of this invention, including the best method of performing it known to us: Nam ofApiat including the best method of performing it known to us: This invention relates to a toilet.

It is known to provide for chemical treatment of excreta and urine in portable toilets.

This invention is directed to the use of a flame to dehydrate excreta and to evaporate urine and of course burn up toilet paper.

Such a technique is to be preferred in many applications where the use of chemicals is considered to be environmentally unfriendly, and further, where the volume of use may exceed the reasonable capacity of chemicals to treat the materials in a short time.

1 0 If dehydration is used, then there needs to be only a supply of energy to effect the dehydration from time to time, and an eventual removal of remaining solids in the form of a small pile of ashes which might be considered much more environmentally friendly.

The invention however is directed to a means for achieving a toilet of this type S1 5 and to provide preferable features which avoid some of the difficulties which have been experienced in development of this type of toilet.

In one form of this invention this can be said to reside in a toilet including a toilet seat, a cover for the seat having two positions, one position being a seat covering position and the other position being an open position, an excreta 2 0 and urine collection tray beneath the toilet seat to collect excreta and urine, the collection tray being positioned and connected to the seat cover so as to be in a collection position with the cover open, and in a tipping position when the seat cover is closed, a holding tray position so as to collect excreta and urine tipped from the collection tray, a burner position to direct a flame onto contents of the holding tray, means to light the burner upon a closure of the seat cover, and means to extinguish the flame upon either the seat cover being opened or through timer means so that a selected time period is measured as having elapsed from the lighting of the burner.

What is being proposed therefore is a toilet in which immediately after use, the 3 0 excreta and urine are tipped into a holding tray which is then directly subject to 3 a burner which will burn for a sufficient time to effect a full dehydration of the contents of the tray.

In practice, there is a source of gas and there are appropriate ignition means activated by the closing of the toilet seat lid, and there are then timer means to effect a burning for a period that in practice has been found to be usefully about 20 minutes.

A first problem is that with such an arrangement, it would be highly undesirable that the subsequent user intending to use the toilet before the expiry of the selected time period should be exposed to any burning flame or 1 0 to any visual sighting of the material being burned.

Accordingly, in preference the collection tray, when in a collection position, is *o o 0 positioned and shaped so as to close access through the seat to the holding tray.

This then has the result of making sure that as the toilet seat lid is opened, this will have the result firstly of stopping the flame from further burning, and will revert the collection tray to a collection position which also closes off both access to the seat area of otherwise hot air from the burning location, and also ***visual sighting of the materials being burnt.

Temporary suspension of the burning has been found not to be of concern and the burning of a further collection of excreta and urine can still be handled and the burning period is selected so as to take account of larger amounts as necessary.

One undesirable feature of using a collection tray and attempting to remove contents of this tray into a second holding tray, is that by the nature of excreta, some of the materials will tend to remain adhering to the collection surface.

In preference then it is provided that when the collection tray is in a tipping position, the collection surface is lowermost and will be subject to some of the burning effect of the flame from the burner to effect dehydration of any surface adhering materials. Such in effect will also have the advantage of also 3 0 sterilising the surfaces as well.

One of the difficulties with an arrangement such as that described is that for such a toilet to be most useful, it would be better if it was fully portable and did not rely on an external supply of power.

In preference then there are provided timer means which are controlled by a battery supply.

One of the disadvantages however of using a battery supply is that in order not to unduly quickly flatten the battery, care needs to be taken in design of the toilet so as not to have an ongoing battery current required unnecessarily.

Toilets of the type being described when being used in industrial applications 1 0 can be expected to subject to severe handling and may be overlooked as far o as regular maintenance is concerned from time to time.

.Considering the need to conserve battery power and also in order to provide reasonable safety and also reasonable warning to each person who might be going to use the toilet that something is going to be wrong, there is provided 1 5 as one means of detecting a problem, a means to detect the existence of an elevated temperature subsequent to the apparatus being activated to ignite a flame and in the event that such an elevated temperature is not detected, there being effected an error signal.

In preference, such error signal can be used then to release an interlock which 20 will then stop the toilet lid from being opened and either separately or as well provide a visual and or audio signal to indicate that there is a problem.

The type of problems that can occur are for instance, that the gas bottle supplying gas for burning has run out, a pilot flame from which the burner is to be lighted has gone out, there is some fault in the ignition system.

There can be conventional safety means by which when the pilot light goes out, there is a thermo detector which will then close the main gas supply.

The problem arises however, that if the toilet is not operating, there are circumstances when it would be better for people however even though this will result in unburned material building up within the holding tray.

One feature of the arrangement described is that there can be provided interlocking means for the seat which however can be manually over ridden so that the person manually over riding the interlock, is aware of the fault but makes a decision to use the facilities anyway.

In preference the timer means are electronic components providing for the selected period of burning to be effected. In the event of a failure of the electronic components, and even in the event of the battery going flat, it is of value to consider whether there can be a useful solution which maintains at least some value in the apparatus as a whole despite a malfunction.

1 0 In preference then, there is provided a manual switch by which flame can be initiated from the burner where the period of burn is simply determined the manual user through switch control means.

In such a way, apart from gross malfunction or in the absence of gas, a reasonable dehydration of the contents can be manually effected from time to 1 5 time until a service can be effected on the electronic components or the battery or other elements or replacements can be effected.

As will now be seen, there has been provided advantageous features and in order to better understand these and other features reference will now be made to a preferred embodiment which shall be described with the assistance of drawings wherein: FIG 1 is a side elevation partly in cross section of the first embodiment shown with a seat cover in a closed position; FIG 2 is the same view as in FIG 1 of the same embodiment with the seat cover shown in an open position; FIG 3 is a perspective view of the same embodiment as in FIGS 1 and 2 shown with part cut away however with in this case the lid being shown in the open position and with a front panel being shown in an open position and a rear cover being partly separated; FIG 4 is a cross sectional view of the embodiment as shown in FIGS 1 3 0 through 3 with the toilet seat cover being shown in a lowered position; FIG 5 is a perspective view showing the arrangement for effecting a starting of the flame from the burner and also starting a timer cycle; FIG 6 is an external perspective view of the toilet with the seat cover open; FIG 7 is a more detailed view in perspective and part cut away of the holding tray; FIG 8 is a perspective view of the components providing for an interlock in respect of the removal of the holding tray; FIG 9 is the same view as in FIG 8 showing the interlock in effect its o:i purpose being to stop the removal of the holding tray when a flame is burning; 10 and S-FIG 10 is a circuit diagram of a timer used for the embodiment.

Now referring to the drawings in detail: The toilet 1 includes a toilet seat 2 and a cover 3.

A body 4 of the toilet is defined by having a top 5 two sides 6 and 7 and a bottom 8.

At the front of the body 4 is a door 9 which can be opened by pivoting about a lower edge at A rear panel 11 with a number of vents 12 completes the description of the outside structure of the body 4.

A vent 13 with an outside thermal sleeve 14 provides for venting of hot gases resulting from burning of the materials inside the toilet.

Within the body 4 and immediately beneath the hole 15 of the seat 2 there are provided inwardly inclined walls such as at 16, 17, 18 and 19 which at there bottom define an approximately square aperture in which a collection tray is fitted.

The collection tray 20 is pivotally supported at both sides at 21 and 22 and the position of the collection tray 20 is governed by the position of crate 23.

The collection tray is in the form of a shallow tray with sides shown typically at 24 and which define an upper perimeter shape which matches fairly closely with the bottom aperture left by the walls 16, 17, 18 and 19.

Positioned beneath the collection 20 is a holding tray 25 into which any contents within the tray 20 are deposited will be tipped.

The tray 25 is adapted to be removable by being slidable in position through the area left by door 9 when this is opened.

i' 10 The tray 25 is positioned so as to be subject to the issue of flame from burner 26.

There are conventional means shown at 27 whereby to effect an ignition of a gas air mixture issuing from burner 26.

The cover 3 is pivotally supported at 28 to the top 5 and has secured thereto an arm 29 which is rigidly secured to the cover 3 so as to rotate with the cover S-3.

The end of the arm 29 is coupled pivotally to link 30 which has at its other end a pivotal connection 31 to arm 32 the bottom of which is pivotally supported with respect to wall 34.

There is then a link 35 from the pivot connection 31 to crank arm 23.

The result of this linkage coupling is that when the cover 3 is opened, the collection tray 20 is in the collection position as shown in figure 2, 3 and others and when the cover 3 is closed as in figure 1, then the linkage will cause the tray 20 to be turned around the other way so that its previously uppermost surface is now lowermost and of course its contents would at least mostly then have been tipped into the holding tray When the cover 3 is first opened and then closed again, as shown in figure shaft 36 which is an extension of arm 32, causes a blade 37 to engage the contacts 38 of a switch 39 which in turn does two things. The first is that it initiates through connection 40 a start of the release of gas and ignition of this and it also causes a reset in battery driven electronic timer 41 which is set so that once the initiation has been commenced, this will continue to hold the circuit closed for a selected period of time chosen at 20 minutes at the present time, before again opening the circuit stopping gas supply and extinguishing any flame.

An interlock 42 is arranged to stop the removal of the tray 25 when the cover 3 is closed. This is to ensure that the tray 25 is not removed while a flame is alight from burner 26.

A few features of the arrangement described will now be pointed out: When the cover 3 is closed, and with the collection tray turned over, this will have the effect that any flame issuing from the burner 26 while being directed into the open top of the holding tray 25, nonetheless will have the result that 1 5 rising heat will directly impinge onto the underneath surface of the collection tray 20 both to an extent to burn off any adhering excreta and otherwise sterilising the tray -The shape and position of the tray 20 is such as to also contribute to a burning path 42 which will then continue into the vent 13 to be vented to the 2 0 atmosphere.

The timer 41 is operated so that it will restart on each activation of switch 39.

It will be noticed that blade 37 will not engage the contact 38 of the switch 39 unless the cover 3 is fully opened so that a partial opening of the cover 3 will allow casual observation of the operation of the mechanism without causing this to go through a 20 minute burn.

Incidental features including ample insulation at 43 are to ensure that the top will not become unduly hot and therefore potentially burn bare skin of a user.

There are furthermore externally accessible switch means which are not specifically shown which allow for manual override of the timer 41 and is such 3 0 as to allow for manual control of the time and the initiation of the burn provided however in the preferred instance that the cover 3 is closed.

This allows for effective manual operation in the event that any battery within the timer 41 fails or some of the electronic components fail or some of the other elements in the circuitries do fail such as the microswitches in switch 39.

A full description of the circuit as shown in FIG 10 is now given: The timer is designed to operate the gas burner within the gas toilet for a period of 20 minutes whenever the lid is closed. Each time the lid is opened and closed, a new 20 minute cycle is initiated. The gas burner is monitored by an approved combined gas control. This control consists of a valve body, 10 manual gas igniter, pilot outlet with pilot thermocouple monitor, and main outlet with thermopile monitor. Once the pilot has been lit and established, the thermopile generates sufficient millivoltage to energise the main burner solenoid when the circuit is closed. The control of the main burner is done by the timer. Over temperature cut out switches are wired into the solenoid circuit, as are the lid switches.

With reference to the circuit diagram, the timer operation is as follows: S"The timer function is done by U1 which is a CMOS timer IC. When the lid is up, the lid switches are as shown in the circuit (Note that under normal conditions, the over temperature switches would be closed). Both lid switches 20 are in series with the solenoid circuit, breaking the current path through the switching MOSFET, TRI. The switch connected to P1 also takes the gate drive from TR1 through the low impedance thermopile for added protection.

The open circuit switch connection to P2 allows the Master Reset pin of U1 to rise via R1 to reset the timer IC. This places the IC into a ready state to begin a new cycle. When the lid is closed, the solenoid circuit is closed, and the MR pin is pulled low via connector P2 through the low impedance thermopile.

This releases the timer to begin a timing cycle. The length of the cycle is defined by the oscillator frequency and the configuration of the pre-scalar inputs, A and B. In this circuit, the pre-scalar is set to 65, 536, with the 3 0 oscillator frequency set by R7 and C5 to produce a cycle time of approximately minutes. At the completion of the timing cycle, output Q is switched low to remove gate drive from TR1 and also inhibits the oscillator via diode D3. This greatly reduces operating current, and hence increases battery life. Zener diode D5 has been included to reduce the gate voltage from TR1 by approximately 3.3V. This ensures that TR1 will cease to operate prior to U1 becoming unpredictable during low voltage conditions, such as would be expected as the battery is nearing the end of its operational life. Switch S1 was added specifically for battery changeover. When it is in the condition shown in the circuit diagram, the gate drive to TR1 is removed via D6 hence preventing any unpredictable burner operation, and the pre-scalar input, B, is pulled low to change the pre-scalar to 256. This reduces the timer cycle time by a factor of 256 which corresponds to approximately 4.6 seconds. This 1 0 means that once the new battery has been inserted, providing that the inhibit switch, S1, is left on for a time exceeding 5 seconds, the timer will be left in the ready state rather than at some unidentified state.

9*o.

All values in the circuit have been chosen for maximum battery life.

Calculations indicate that using a PP3 9V alkaline battery, battery life should exceed 12 months.

Accordingly, the toilet can be used on a temporary basis.

Also not shown but in a preferred instance incorporated, is an over temperature detector which if an over temperature is detected, will operate to again stop the flame from further operation.

A further preferred feature which is not specifically shown in the drawings includes a further higher temperature detector which will come into effect upon a selected delay from start up and being such that it will remain closed provided there is a sufficient temperature indicating that the flame is burning.

If not, this will then initiate a close down and a warning through an error signal being generated within the timer 41 which can then be used to effect either one or more of an audible alarm either continuous or beeping, a visual alarm in the form of a light emitting diode or a leg which is allowed to intercept operation of the linkages connected to the cover 3 so that these will no longer be free to operate except if the interlock is manually withdrawn.