United States Patent 3703732
Abstract:
A combustion toilet for incinerating human waste with a lower incinerating chamber and an upper chamber which receives the waste and is closed by a lid. The waste falls on a butterfly valve which is mounted between the two chambers and is mechanically linked to the lid so as to deposit the waste into the lower chamber when the lid is closed. A mercury switch is mounted for rotation with the valve so as to be electrically closed when the lid is closed and is electrically connected to a manually actuable timer and gas valve so that the gas valve admits gas, such as propane, butane or natural gas, into the lower chamber to incinerate the waste only while the mercury switch is closed and the timer remains actuated. Preferably, a solenoid is provided to prevent closing the lid until the timer is actuated, as well as a heat sensor mounted outside the lower chamber for cutting off gas flow whenever the sensed temperature exceeds predetermined limits.
Application Number:
05/151875
Publication Date:
11/28/1972
Other Classes:
4/111.2, 4/111.4, 4/111.5
International Classes:
A47K11/02; (IPC1-7): A47K11/02; A47K11/00; A41k011/02
Field of Search:
4/131,132,118 110
Primary Examiner:
Matteson, Frederick L.
Assistant Examiner:
Artis, Henry K.
Claims:
WHAT IS CLAIMED IS
1. A combustion toilet for the incineration of human waste comprising:
2. A toilet as in claim 1 further including heat sensing means mounted in said housing outside said lower chamber having a heat switch with an open and a closed condition which shifts from one of said conditions to the other of said conditions whenever the temperature at said heat sensing means exceeds a predetermined limit and wherein said circuit means electrically connects to said heat switch means so that application of said given signal to said valve means is terminated whenever said heat switch is in its other condition.
3. A toilet as in claim 1 wherein said lower chamber is disposed in a manually removable drawer.
4. A toilet as in claim 1 further including solenoid means electrically connected to said timer means for mechanically latching said valve member in said first position until said timer means is manually actuated.
Description:
BRIEF DESCRIPTION OF THE PRIOR ART AND SUMMARY OF THE INVENTION
The invention relates to a combustion toilet for incinerating human waste.
Disposing of human wastes at locations, such as camp grounds, construction sites, remote military and recreation facilities, where conventional sewage systems are impractical is an increasing problem. Burial is a considerable and continual chore which becomes increasingly unsatisfactory as more and more people crowd such areas. Chemical toilets are expensive, complex and not always satisfactory in operation.
Combustion toilets represent one particularly satisfactory way of disposing of human wastes, particularly at such locations where conventional sewage systems are impractical. Such toilets, which can be portable or permanently fixed, have a housing which bounds an inner combustion chamber into which the waste is conventionally deposited. A combustion fluid -- such as butane, propane or natural gas -- is directed into the combustion chamber where it ignites and burns human waste therein, both liquid and solid. The patent to Duncan U.S. Pat. No. 3,320,907 shows one such combustion toilet.
The present invention relates to a combustion toilet of this type which has an upper chamber for receiving waste directly through an upper opening which can be closed by a conventional lid. Waste falling into this upper chamber is deposited upon a butterfly valve which is mounted between the upper chamber and a lower combustion chamber. The butterfly valve is mechanically linked to the lid so as to rotate as the lid is closed and deposit the waste into the lower chamber.
A mercury switch is mounted for rotation with the butterfly valve and is connected to a conventional gas valve which, when a given electrical signal is applied, permits combustion fluid from a suitable source to flow into the combustion chamber and be ignited there, for example by a pilot light. When no such signal is applied, the gas valve prevents such flow. A conventional timer including a switch which is closed for a given time period when the timer is manually actuated is also provided with the timer switch also electrically connected to the gas valve so that the given signal is applied to the gas valve only while both the timer switch and mercury switch remain closed. Thus combustion takes place only while the lid is closed preventing use during combustion and only for a time interval sufficient to complete combustion.
According to a further aspect of the invention, a heat responsive element such as a thermostat switch is mounted within the housing, but without the combustion chamber. This element is also electrically connected to the gas valve so that, when the temperature sensed by the element exceeds a predetermined value, the gas valve ceases delivering combustable fluid to the combustion chamber. Further a solenoid is also preferably mounted in the housing for engaging the butterfly valve and preventing the closure of the lid and rotation of the butterfly valve until the timer is actuated. Thus the timer must be actuated after each use before the lid can be closed.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cut-away side view of one embodiment of the combustion toilet of this invention;
FIG. 2 shows a front view of the embodiment of FIG. 1 with part of the housing removed;
FIG. 3 shows a view of FIG. 2 along the line 3--3; and
FIG. 4 shows a schematic of the circuit for controlling the embodiment of FIG. 1.
DETAILED DESCRIPTION OF THE DRAWINGS
Reference is now made to FIGS. 1-3 which show one embodiment of this invention. Combustion toilet 20 includes a housing 22 which encloses upper chamber 24 and lower combustion chamber 26. Housing 22 may be of any suitable material. Upper chamber 22 is open at the top as shown for conventionally receiving human wastes -- solid and liquid -- which fall directly onto the flat surface of butterfly valve 28 which forms the bottom of chamber 24. Chamber 24 is bounded on two sides by inclined walls 30 and 32 which guide errant material onto valve 28.
After use, a button 34 conveniently mounted on the side of toilet 20 is pressed by the user to initiate a timed combustion cycle. Button 34 is electrically linked, as shown in FIG. 4, to a conventional timer 36 which is mounted as shown in FIGS. 2 and 3 within housing 22. The passage of electrical current through timer 36, which results when button 34 is depressed, causes timer 36 to close its two controlled switches 40 and 42 which remain closed for a predetermined time sufficient to incinerate any reasonable quantity of waste.
The closing of switch 42 completes a current path through conventional solenoid 44 which is mounted outside chamber 26 as shown in FIGS. 2 and 3. Solenoid 44 controls a latch member 48 which is continuously urged by spring 49 toward shaft 52 which couples valve 28 to gear 54. Member 48 is journaled for movement toward and away from shaft 52 in a hollow tube 50 and in its normal forward position latch member 48 engages a groove in shaft 52 and prevents rotation of member 52, and hence valve 28, in the direction indicated by arrow 56. The flow of current through solenoid 44 which results when switch 42 closes causes latch member 48 to be withdrawn and remain withdrawn as long as timer 36 keeps switch 42 closed.
After button 34 has been manually depressed, completing a current path through timer 36 and causing switches 40 and 42 to close, lid 60 can be closed to dump the waste on valve 28 into combustion chamber 26 where it is consumed. Lid 60 is mechanically connected to gear 54 by an intermediate link 64 and a rack 62 having teeth which mesh with the teeth of gear 54 as shown in FIGS. 1 and 3. As lid 60 is closed, link 64 pivots about shaft 66 and pulls rack 62 back toward timer 36 so that gear 54, and valve 28 pivot through roughly 180° in the direction of arrow 56 and material on valve 28 is dumped into combustion chamber 26 where the solid material rests on grate 67 and the liquid material on the floor 68 of chamber 26. Solenoid 44 thus prevents closing lid 60 without initiating the combustion cycle by pushing button 34 and serves to prevent accumulation of unburned material in upper chamber 24. Lid 60, however, can always be raised from its lowered position to use toilet 20.
A conventional mercury switch 70 is mounted outside chambers 24 and 26 for rotation with valve 28 so that switch 70 assumes an electrically open condition when the lid is up and valve 28 is in the position where waste is received on it and an electrically closed condition when the lid is closed and valve 28 is thereby rotated through 180° to dump the waste into chamber 26. Thus, the rotation of valve 28 in the direction indicated by arrow 56 closes switch 70 and completes a current path through conventional gas valve 72 which permits gas to flow into chamber 26 via line 74 and be ignited therein, for example by a pilot light. Waste in chamber 26 is thus incinerated.
At the end of the time interval for which timer 36 operates, switches 40 and 42 open, interrupting current flow through gas valve 72 and solenoid 44. Delivery of gas to chamber 26 thus ceases and latch member 48 returns to its forward position which does not, however, preclude rotation of valve 28 in a direction opposite to arrow 56. Thus the seat can now be raised and the above process repeated. If use of toilet 20 is desired before the timing cycle is complete, lid 60 can be raised at any time, rotating valve 28 back to its initial position and causing switch 74 to open. The opening of switch 74 cuts off the current flow through valve 72 which in turn interrupts delivery of gas to chamber 26 until the lid is again closed. If used, timer 36 should be reset by pushing button 34 in order to initiate a new complete cycle.
As a safety precaution, a normally closed temperature responsive switch 76 is mounted below timer 36 as can be seen in FIGS. 1 and 2. In the event that the temperature sensed by this switch exceeds predetermined limits switch 76 opens and, as shown in FIG. 4, interrupts the current flow through gas valve 72.
The gaseous products of combustion escape from chamber 26 through a double walled flue 78. Further, housing 22 is provided with an opening in the front which affords access to a drawer 80 which can be removed by pulling handle 82 outward. Cleaning chamber 26 can be easily and expeditiously accomplished by removing drawer 80.
Many changes and modifications in the above embodiment of the invention can of course be made without departing from the scope of the invention and accordingly that scope is intended to be limited only by the scope of the appended claims.