Antiviral mobile respiratory personal protection device

Abstract

Invention is described which sterilizes air contaminated with airborne virus by means of superheating the air to over 400 Fahrenheit then cooling air to breathable temperatures. The invention disposes a fan pushing contaminated air into a positive temperature coefficient semiconductor heater to superheat the air which is subsequently cooled by a two stage cooling system. First stage of the cooling system is an air-to-air heat exchanger using ambient air from second fan to cool the superheated air. The second stage of cooling is provided by a solid-state Peltier heat pump which further transfers heat energy to ambient air provided by a third fan. Invention is disposed onto a sealed helmet which the sterilized air is conveyed causing an overpressure to eliminate the possibility of contaminated air entering the helmet. The invention is entirely reusable after use in a contaminated environment and does not rely on filters to remove airborne virus.

Claims

1. A wearable air sterilizer comprising: a first fan configured to ingest contaminated ambient air and direct said contaminated ambient air through an interconnecting duct; a PTC heater configured to receive the contaminated ambient air from the first fan through the interconnecting duct and heat the contaminated ambient air above 400 degrees Fahrenheit to create a heated air; a residence duct configured to receive the heated air, wherein a residence time of the heated air in the residence duct is determined based on a length of the residence duct and a speed of the heated air in the residence duct, in order to sterilize the heated air via physical rupture of a pathogen cell structure to create sterilized heated air; a first stage of cooling utilizing an air-to-air heat exchanger configured to receive the sterilized heated air from the residence duct and convey the sterilized heated air into a cooling passage which is configured to cool the sterilized heated air to create a lower intermediate temperature sterilized air; a second fan configured to ingest a second cool, contaminated ambient air and direct said second cool, contaminated ambient air into a heating passage of the air-to-air heat exchanger configured to transfer heat energy from the sterilized heated air to the second cool, contaminated ambient air while maintaining isolation between the sterilized heated air and the second cool, contaminated ambient air; an intermediate duct providing a structure to isolate and convey the lower intermediate temperature sterilized air from the air-to-air heat exchanger to a second stage of cooling; the second stage of cooling utilizing a cold side of a Peltier heat pump configured to receive the lower intermediate temperature sterilized air from the intermediate duct and cool the lower intermediate temperature sterilized air by using a third fan configured to ingest a third cool, contaminated ambient air and direct said third cool, contaminated ambient air into a hot side of the Peltier heat pump to transfer heat energy from the lower intermediate temperature sterilized air to the third cool, contaminated ambient air in order to create a cooled sterilized air provided at a comfortable and breathable final air temperature; and a final duct configured for conveying the cooled sterilized air to a wearer.

2. An air sterilizer comprising: a helmet with a sealed clear visor; an elastic membrane covering a bottom area of the helmet with an aperture configured for allowing a user's head to pass into the helmet, whereby the elastic membrane is configured to form a seal around the user's neck; a first fan mounted on said helmet with vibration mounts, and configured to ingest contaminated ambient air and direct said contaminated ambient air through an interconnecting duct; a PTC heater mounted on said helmet with vibration mounts, and configured to receive the contaminated ambient air from the first fan through the interconnecting duct and heat the contaminated ambient air above 400 degrees Fahrenheit to create a heated air; a residence duct mounted on said helmet, and configured to receive the heated air, wherein a residence time of the heated air in the residence duct is determined based on a length of the residence duct and a speed of the heated air in the residence duct, in order to sterilize the heated air via physical rupture of a pathogen cell structure to create sterilized heated air; a first stage of cooling utilizing an air-to-air heat exchanger mounted on said helmet, and configured to receive the sterilized heated air from the residence duct and convey the sterilized heated air into a cooling passage which is configured to cool the sterilized heated air to create a lower intermediate temperature sterilized air; a second fan mounted on said helmet with vibration mounts, and configured to ingest a second cool, contaminated ambient air and direct said second cool, contaminated ambient air into a heating passage of the air-to-air heat exchanger configured to transfer heat energy from the sterilized heated air to the second cool, contaminated ambient air while maintaining isolation between the sterilized heated air and the second cool, contaminated ambient air; an intermediate duct mounted on said helmet, and providing a structure to isolate and convey the lower intermediate temperature sterilized air from the air-to-air heat exchanger to a second stage of cooling; the second stage of cooling utilizing a cold side of a Peltier heat pump mounted on said helmet, and configured to receive the lower intermediate temperature sterilized air from the intermediate duct and cool the lower intermediate temperature sterilized air by using a third fan mounted on said helmet with vibration mounts, and configured to ingest a third cool, contaminated ambient air and direct said third cool, contaminated ambient air into a hot side of the Peltier heat pump to transfer heat energy from the lower intermediate temperature sterilized air to the third cool, contaminated ambient air in order to create a cooled sterilized air provided at a comfortable and breathable final air temperature; and a final duct mounted on said helmet, and configured for conveying the cooled sterilized air into the helmet.

3. An air sterilizer comprising: a helmet with a sealed clear visor; an elastic membrane covering a bottom area of the helmet with an aperture configured for allowing a user's head to pass into the helmet, whereby the elastic membrane is configured to form a seal around the user's neck; a first fan mounted on said helmet with vibration mounts, and configured to ingest contaminated ambient air and direct said contaminated ambient air through an interconnecting duct; a PTC heater mounted on said helmet with vibration mounts, and configured to receive the contaminated ambient air from the first fan through the interconnecting duct and heat the contaminated ambient air to above 400 degrees Fahrenheit to create a heated air; a residence duct mounted on said helmet, and configured to receive the heated air, wherein a residence time of the heated air in the residence duct is determined based on a length of the residence duct and a speed of the heated air in the residence duct, in order to sterilize the heated air via physical rupture of a pathogen cell structure to create sterilized heated air; a first stage of cooling utilizing an air-to-air heat exchanger mounted on said helmet, and configured to receive the sterilized heated air from the residence duct and convey the sterilized heated air into a cooling passage which is configured to cool the sterilized heated air to create a lower intermediate temperature sterilized air; a second fan mounted on said helmet with vibration mounts, and configured to ingest a second cool, contaminated ambient air and direct said second cool, contaminated ambient air into a heating passage of the air-to-air heat exchanger configured to transfer heat energy from the sterilized heated air to the second cool, contaminated ambient air while maintaining isolation between the sterilized heated air and the second cool, contaminated ambient air; an intermediate duct mounted on said helmet, and providing a structure to isolate and convey the lower intermediate temperature sterilized air from the air-to-air heat exchanger to a second stage of cooling; the second stage of cooling utilizing a cold side of a Peltier heat pump mounted on said helmet, and configured to receive the lower intermediate temperature sterilized air from the intermediate duct and cool the lower intermediate temperature sterilized air by using a third fan mounted on said helmet with vibration mounts, and configured to ingest a third cool, contaminated ambient air and direct said third cool, contaminated ambient air through a supply duct into a hot side of the Peltier heat pump to transfer heat energy from the lower intermediate temperature sterilized air to the third cool, contaminated ambient air in order to create a cooled sterilized air provided at a comfortable and breathable final air temperature; and a final duct mounted on said helmet, and configured for conveying the cooled sterilized air into the helmet; a one-way pressure valve disposed in the helmet, and configured to release air from an inside of the helmet to an ambient environment outside of the helmet at a preset pressure, while preventing contaminated ambient air outside of the helmet to enter the inside of the helmet; a first temperature sensor configured to measure an ambient air temperature; a second temperature sensor configured to measure an air temperature of the heated air as it leaves the PTC heater; a third temperature sensor configured to measure an air temperature of the sterilized heated air as it leaves the air-to-air heat exchanger; a fourth temperature sensor configured to measure an air temperature of the cooled sterilized air as it leaves the Peltier heat pump; a fifth temperature sensor configured to measure an air temperature inside the helmet; an oxygen sensor configured to measure oxygen in the air inside the helmet; an air pressure sensor configured to measure an air pressure inside the helmet; and a control system configured to use information from the first temperature sensor, the second temperature sensor, the third temperature sensor, the fourth temperature sensor, the fifth temperature sensor, the oxygen sensor, and the air pressure sensor to independently control operation of the first fan, the second fan, the third fan, the PTC heater, and the Peltier heat pump.

4. The air sterilizer of claim 3, wherein electrical power for the first fan, the second fan, the third fan, the PTC heater, the Peltier heat pump, and the control system is provided by at least one rechargeable battery carried on a belt configured to be worn by the user and electrically connected to the helmet via quick disconnect cables.

5. The air sterilizer of claim 3, wherein a flat flexible membrane is disposed in a lower front of the helmet such that one side of the flexible membrane is configured to be exposed to the ambient environment outside of the helmet while an opposite side of the flexible membrane is configured to be exposed to the air inside of the helmet, such that sound energy is configured to be transmitted outside of the helmet.

6. The air sterilizer of claim 3, further comprising a display disposed such that operational parameters are displayed and configured to be visible to the user while wearing the helmet.

7. The air sterilizer of claim 3, further comprising a radio communication system including a radio disposed on a belt configured to be worn by the user, the radio configured to be electrically connected to the helmet via quick disconnect cables.

Description

DRAWINGSREFERENCE NUMERALS

(1) FIG. 1 is a top view perspective view of invention;

(2) FIG. 2 is an isometric exploded view of the PTC air heater sub-system;

(3) FIG. 3 is an isometric exploded view of the first stage cooling sub-system utilizing an air-to-air heat exchanger;

(4) FIG. 4 is a detailed internal view of the air-to-air heat exchanger used in the first stage cooling subsystem;

(5) FIG. 5 is an isometric internal view of the second stage cooling sub-system utilizing a Peltier solid state heat pump;

(6) FIG. 6 is a view of the invention as worn by a user;

(7) FIG. 7 is an electrical architecture block diagram illustrating the interconnection of various electrical components in a preferred embodiment of the present invention.

DETAILED DESCRIPTION

(8) This invention disposes a Positive Temperature Coefficient (PTC) semiconductor thermistor heater to heat contaminated air in a first cool, contaminated ambient air stream to a temperature of over 400 degrees Fahrenheit. This temperature of over 400 degrees Fahrenheit in combination with the time at this temperature in the invention's residence duct causes physical rupture of a pathogen cell structure and therefore renders the pathogen to a state that does not pose a health risk. The air so heated is named here heated sterilized air and although sterilized, it is too hot to safely breathe as it would cause thermal injury to a person. In the invention herein, the heated sterilized air is then cooled by means of two stages of cooling to a temperature that is safe and comfortable for breathing. In the first stage of cooling, an air-to-air heat exchanger cools the heated sterilized air by the transfer of heat energy from the heated sterilized air to a second cool, contaminated ambient air stream. In the invention, the heated sterilized air thus cooled is called here lower intermediate temperature sterilized air. In the second stage of cooling, a solid-state Peltier heat pump transfers heat energy from the lower intermediate temperature sterilized air to a third cooled, contaminated ambient temperature air stream which further cools the sterilized air down to a safe breathable temperature. The air thus cooled is called here final air temperature sterilized air and is provided to the wearer for breathing. A system of three variable speed fans is used to provide required air flow in the invention. The first fan provides air flow from the contaminated external ambient environment into the PTC semiconductor thermistor heater and after cooling, provides positive air pressure to the helmet. The second fan provides air flow from the contaminated external ambient environment to the air-to-air heat exchanger for the first stage of cooling. The third fan provides air flow from the contaminated external ambient environment to the Peltier hot side to form the second stage of cooling.

(9) This invention is shown in FIG. 1 integrated with a helmet structure (22) where contaminated environmental air is drawn into the invention through a coarse screen (1) and optional HPEA filter (2) by the action of the first fan (3) which is mounted to the helmet structure with a vibration mount (4). The ambient environmental air temperature flowing into the invention is measured by a temperature probe (5) and used by the control system. The contaminated air then flows via (6) into the PTC semiconductor thermistor heater (7) to be superheated to above 400 degree Fahrenheit.

(10) The PTC semiconductor thermistor heater (7) is mounted to the helmet structure by a thermally insulated mount (8). The air temperature at exit from the PTC semiconductor thermistor is measured by a temperature probe (9) and used by the control system for safe operation.

(11) The exit airflow from the PTC semiconductor thermistor heater (7) called heat air flows into the residence duct (10). The length of the residence duct (10) in combination with the heated airflow speed determines the residence time of the heated air prior to stage one cooling. This residence time in combination with the temperature above 400 degrees Fahrenheit renders the virus non-functional. Therefore, the residence duct length (10) is designed to provide the required residence time at temperature for effective virus elimination. The air exiting the residence duct in the invention is here called heated sterilized air as the air has been both heated to a temperature above 400 degrees Fahrenheit to accomplish sterilization.

(12) Continuous air flow is integral to the use of PTC semiconductor thermistor heaters for this invention. This continuous air flow combined with heated air temperature above 400 degrees Fahrenheit also dries the air and so eliminates moisture accumulation as an issue in or outside of the invention.

(13) The first stage air cooler is an air-to-air heat exchanger (13) with a second ambient temperature airflow heat sink provided by the second fan (11). The second fan (11) is affixed to the helmet via vibration mount (12). The heated sterilized air enters the air-to-air heat exchanger via residence duct (10) and exits via intermediate duct (15). The air-to-air heat exchanger (13) must be insulated due to the safety risk from the surface temperature of the heat exchanger. The heat energy taken from the heated sterilized airflow is exhausted to the environment externa helmet by duct (57). The intermediate duct (15) is also insulated to reduce the safety risk from the hot surface of the intermediate duct. The lower intermediate temperature sterilized air exiting from the air-to-air heat exchanger in the intermediate duct (15) is measured by a temperature probe (14) and used by the control system for safe operation.

(14) The lower intermediate temperature sterilized air in the intermediate duct (15) after the stage of cooling is still too hot to safely breath until it flows through the second stage cooler which consists of a Peltier Heat Pump (16) contained in a bi-duct reverse flow arrangement. The Peltier Heat Pump moves heat energy from the incoming lower intermediate temperature sterilized air to the third cool, contaminated ambient air flow supplied via the third fan (17) which is affixed to the helmet structure via a vibration mount (18). The third cool, contaminated ambient air flow is in reverse flow to the lower intermediate temperature sterilized air flow direction and is exhausted to the external environment by duct (40). The second stage of cooling creates the final air temperature sterilized air in the invention.

(15) The air exiting Peltier Heat Pump through the final duct (20) is final air temperature sterilized air and is measured by a temperature probe (19) which is used by the control system for safe operation.

(16) The final air temperature sterilized air flows into the airspace inside the helmet structure via duct (20). This over-pressurizes the helmet in order to always maintain an outflow of sterilized air from the helmet which eliminates potential inflow of external contaminated air to the inside of the helmet. This over pressurization is controlled via a one-way pressure valve (21) such that no external contaminated air can flow into the helmet, but at a preset pressure, sterilized air is released into the external environment such as when the user exhales. A display (23) of system parameters including sterilization status is provided so that the user can easily and continuously view the status while wearing the helmet.

(17) The helmet interior air temperature is measured by a temperature probe (25) and used by the control system for safe operation. A system power on/off switch (27) is provided near the front of the helmet to be easily accessible to the user. The helmet air oxygen level is measured by a probe (52) and monitored by the control system to indicate safe operation to the user. The helmet air pressure level is measured by a probe (26) and is used by the control system for safe operation. The helmet is sealed with a clear visor (28). Electrical power is provided via quick disconnect power cable (48) from a battery. Radio communications to the helmet is provided via a quick disconnect signal cable (47).

(18) As it is anticipated that the invention will be used in a medical environment where voice communication is important, a sealed acoustic membrane (24) is provided near the mouth area so that sound energy from the users voice is transmitted to the external atmosphere.

(19) FIG. 2 shows further detail of the air heater subsystem. The external contaminated air is ingested into the system through a coarse screen (1) which prevents objects such as fingers, medical curtains, and paper from entering the system. Centrifugal fan (3) has entrance to the impeller (32) oriented to face away from the helmet. The ambient temperature probe (5) is placed at the entrance to the fan such that incoming air flows over the temperature probe. The fan is powered by wires (29) which contain electrical positive and negative. The fan (3) causes the first stream of cool, contaminated air to flow through connecting duct (6) and into the PTC heater (7). The PTC heater (7) has the heater elements arranged in a honeycomb form for maximum heat transfer to the air while limiting pressure loss. The PTC heater is provided with insulation (55) disposed on the exterior to provide a safe surface temperature as the PTC exterior surface temperature is above 400 degrees Fahrenheit and is therefore a safety hazard. The PTC heater is powered by wires (30) which contain electrical positive and negative. The heated air exiting from the PTC Heater (7) flows into the residence duct (10) which is also insulated (31) to provide safe exterior temperatures and reduce heat loss to the ambient environment. The length of the residence duct (10) provides the necessary time at temperature to render the airborne virus organism non-functional.

(20) FIG. 3 shows further detail of the first stage of the inventions cooling system. The second stream of cool, contaminated ambient air is ingested via a centrifugal fan (11) through the fan impeller face (33). The exit flow from this fan flows through a collector (36) and into the air-to-air heat exchanger heating passage through an entrance fitting (35). Heat energy is transferred from the heat sterilized air to the second stream of cool, contaminated ambient air in the heat exchanger (13) and exhausted externally to the environment through a vent (37). The heat sterilized air enters the air-to-air heat exchanger (13) from the residence duct (10) through a fitting (34) and is exhausted at as lower intermediate temperature sterilized air through a fitting (56) into duct (15).

(21) FIG. 4 shows the interior detail of the air-to-air heat exchanger (13) which forms the first stage of the inventions cooling system. A second cool, contaminated ambient air stream proceeds through an entrance fitting (35) and flows through thermally conductive channels (38) which isolates the heated sterilized air flow (36) from the second cool, contaminated ambient air used for cooling. As the heated sterilized air flows through the thermally conductive channels (38) the heat energy is transferred from the heat sterilized air to the second cool, contaminated ambient air. Therefore the heated sterilized air temperature is reduced as it flows towards exit fitting (56) to form intermediate lower temperature sterilized air. Conversely the second cool, contaminated ambient air temperature is increased in the air-to-air heat exchanger as it flows towards the vent (37). Thus, heat from the sterilization process is transferred to the external ambient environment.

(22) FIG. 5 shows further detail of the second stage (16) of the inventions cooling system. The intermediate lower temperature sterilized air entering the second stage is still above safe breathing temperatures, but does not possess sufficient temperature differential in comparison to the ambient air to efficiently cool it via an additional air to air heat exchanger. Additionally, for comfort reasons the ability to cool to air temperatures below ambient is required. Therefore, the inventions second stage cooling system uses a solid-state Peltier heat pump (42) which transfers heat from the intermediate lower temperature sterilized air to the ambient atmosphere. The intermediate lower temperature sterilized air from the first stage cooling system enters the second stage cooling system through intermediate duct (15) and flows across cooling fins (46) that are cooled by a Peltier heat pump (42). The air thus cooled makes final air temperature sterilized air that is both a comfortable breathing temperature and is sterilized. The final air temperature sterilized air flows into the helmet through a final duct (20) with the air temperature being measured by a temperature probe (19).

(23) The Peltier heat pump (42) is positioned between two counter-flowing air ducts to transfer heat energy from the intermediate lower temperature sterilized air in the sterilized air flow duct (45) to the third cool, contaminated air provided through a duct (44). A centrifugal fan (17) mounted to the helmet with a vibration mount (18) ingests a third cool, contaminated ambient air stream which is then directed through a duct (39) going into the second stage cooling unit (16). This third cool, contaminated ambient air then flows across Peltier hot side heat transfer fins (43). The heat energy from the intermediate temperature sterilized air is transferred into this air stream and is therefore transferred into the external environment through an exhaust duct (40).

(24) The second stage cooling system heat transfer is modulated by the electrical power provided by wires (41) from a closed loop control system utilizing the second stage exit temperature probe (19). Thus controlled, the invention can safely operate across a range of ambient temperature conditions.

(25) The entire invention as worn by a person is shown in FIG. 6. The helmet (22) has an elastic neck shroud (576) which lightly seals to the users neck or hazardous material suit. An electrical cable (47) connects the helmet to a radio communication device (49) worn on a belt (51). A further electrical cable (48) provides electrical power to the helmet (22) via battery (50) which is also worn on the same belt (51).

(26) The inventions electrical architecture is shown in FIG. 7 in which a central control device (53) is used to ease manufacturability. A central connector (54) is disposed from the central control device (53) to the fans, sensors, and heat pump. Electrical power provided by a battery (50) comes into the central control module via quick disconnect cable (48). The invention is controlled by an on-off switch (27) which is electrically connected to the central control module. A system display of various parameters (23) is driven by information received from the central control module. The communication radio (49) provides audio signals via quick disconnect cable (47) to the central control module which in turn works with the speaker and microphone element (58) inside the helmet. The central control unit receives temperature measurements in the system from five temperature probes (5) (9) (14) (19) (25), one oxygen sensor (52), and one pressure sensor (26) in order to safely control the system. The central control unit hosts algorithms which modulate the power to three fans (3) (11) (17), one PTC Heater (7), and one Peltier solid state heat pump (16).