Surface sterilization device

• US 5,958,336 A
• Filed: 04/26/1996
• Issued: 09/28/1999
• Est. Priority Date: 04/26/1996
• Status: Expired due to Fees

• Current Assignee: Duarte, Raul
• Original Assignee: Duarte, Raul
• Inventors: Duarte, Raul
• Primary Examiner(s): Feisee, Lila
• Assistant Examiner(s): PAK, MICHAEL D
• Application Number:
  US08/638,144
• Time in Patent Office: 1,250 Days
• Field of Search: 422/24, 422/25, 422/121, 422/186.3, 250/453.11, 250/454.11, 250/455.11
• US Class Current: 422/24
• CPC Class Codes: A61L 2/10 Ultraviolet radiation

Abstract

A device for surface sterilization of objects includes a housing, a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface. At least part of the conveyor bed is located longitudinally within the housing to thereby movably support objects to be surface sterilized as they are passed through the housing from a contaminated area to a clean area. An air filtration system is in communication with the housing, and at least one ultraviolet light assembly is located within of the housing to decontaminate the object to be surface sterilized within the sterilization device as the object is transferred via the conveyor through the housing and into the clean area.

Claims

1. A device for surface sterilization of objects, the device comprising;

a housing having a first end and a second end and extending continuously there between;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate the object to be surface sterilized within the sterilizing device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the conveyor includes a plurality of rollers rotatably connected transversely along substantially the entire length of the conveyor, and further wherein at least the rollers of the conveyor which are positioned within the sterilization chamber are made of fused quartz, to thereby enhance reflection of U.V. rays within the sterilization chamber and increase contact of such U.V. rays with the surface of the object to be sterilized.

2. The device of claim 1, wherein the housing includes an intake portion disposed over the first end of the conveyor, an output portion disposed over the second end of the conveyor, and a sterilization chamber located between and in communication with the intake portion of the conveyor and the output portion of the housing and disposed over a substantially central portion of the conveyor.

3. The device of claim 2, wherein the at least one ultraviolet light assembly is attached to at least one inside wall of the sterilization chamber of the housing.

4. The device of claim 3, wherein the at least one ultraviolet light assembly comprises a plurality of ultraviolet light assemblies positioned spacedly about the interior walls of the sterilization chamber.

5. The device of claim 4, wherein the sterilization chamber includes a plurality of doors, and further comprising at least one ultraviolet light assembly attached to an interior surface of each of the doors of the sterilization chamber.

6. The device of claim 3, wherein the at least one ultraviolet light assembly includes an ultraviolet light bulb and a shield connected to the bulb and positioned to cause ultraviolet light rays from the ultraviolet light bulb to reflect toward the interior of the sterilization chamber, rather than outwardly and away from the interior.

7. The device of claim 1, wherein the air filtration system includes at least one air filtration module having a first filter which is a prefilter, and a second filter, and is capable of filtering out substances which range in size from that of particulate matter to that of microscopic contaminants such as bacteria and viruses, to prevent entrance of such contaminants into the housing.

8. The device of claim 7, wherein the air filtration system includes at least one air filtration module having a filter of the HEPA type.

9. The device of claim 8, wherein the at least one air filtration module comprises a first, a second and a third air filtration module, the first air filtration module being disposed above the intake portion of the housing, the second air filtration module being disposed above the output portion of the housing, and the third filter being disposed above the sterilizing chamber portion of the housing.

10. The device of claim 2, wherein at least one of the intake module, the output module and the sterilization chamber of the housing are open-topped, and connected to and in communication with an air filtration module of the air filtration system.

11. The device of claim 10, and further comprising a first door movably mounted between the intake module of the housing and the sterilization chamber and a second door movably mounted between the output module and the sterilization chamber, and means to effect opening and closing of the first door and the second door.

12. The device of claim 1, wherein the conveyor has more than one segment, and the rollers rotatably connected transversely along the extent of at least one portion of the conveyor are made of fused quartz, and further, the rollers rotatably connected transversely along the extent of at least one other portion of the conveyor are made of aluminum.

13. The device of claim 1, wherein the housing is open-bottomed, and has continuous side walls which extend entirely from the first end of the housing to the second end of the housing.

14. The device of claim 1, wherein the at least one ultraviolet light assembly is capable of providing a total of at least 1600 watts, to thereby assure an adequate bacterial kill rate when an object on the conveyor travels through the device at a rate in the range of approximately 20 to approximately 200 linear feet per minute.

15. The device of claim 1, wherein the at least one ultraviolet light assembly is capable of providing a total of at least 160,000 microwatts per second/cm², to thereby assure an adequate bacterial kill rate as an object on the conveyor travels through the device.

16. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously there between;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate an object to be surface sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the air filtration apparatus is capable of moving air at approximately 960 cfm and a force of approximately 90 fpm.

17. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously there between;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate an object to be sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the conveyor has more than one segment, each one of the more than one segment being capable of operating at a speed independent of the speed at which any other of the more than one segment is operating.

18. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously there between;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate an object to be sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the housing includes an intake portion disposed over the first end of the conveyor, an output portion disposed over the second end of the conveyor, and a sterilization chamber located between and in communication with the intake portion of the conveyor and the output portion of the housing and disposed over a substantially central portion of the conveyor;

wherein at least one of the intake module, the output module and the sterilization chamber of the housing are open-topped, and connected to and in communication with an air filtration module of the air filtration system; and

further wherein all of the intake module, the output module and the sterilization chamber of the housing are open-topped, and the open-topped intake module of the housing is connected to and in communication with a first air filtration module of the air filtration system, the open-topped output module of the housing is connected to and in communication with a second air filtration module, and the open-topped sterilization chamber of the housing is connected to and in communication with a third air filtration module.

19. The device of claim 18, wherein the means to effect opening and closing of the first door and the second door comprises a cable and pulley system mounted on the third air filtration module and connected to the first door and the second door and wherein the first door and the second door are each mounted on tracks, to thereby permit slidable opening and closing upon operation of the cable and pulley system.

20. The device of claim 18, wherein the means to effect opening and closing of the first door and the second door comprises at least one hinge mounted at a top edge of the first door and at least one hinge mounted at a top edge of the second door, to thereby movably connect the first door and the second door between the intake module and the sterilization chamber and the output module and the sterilization chamber, respectively.

21. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously therebetween;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate the object to be surface sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the housing includes an intake portion disposed over the first end of the conveyor, an output portion disposed over the second end of the conveyor, and a sterilization chamber located between and in communication with the intake portion of the conveyor and the output portion of the housing and disposed over a substantially central portion of the conveyor;

wherein at least one of the intake module, the output module and the sterilization chamber of the housing are open-topped, and connected to and in communication with an air filtration module of the air filtration system;

and further comprising a first door movably mounted between the intake module of the housing and the sterilization chamber and a second door movably mounted between the output module and the sterilization chamber, and means to effect opening and closing of the first door and the second door, wherein the means to effect opening and closing of the first door and the second door comprises a cable and pulley system mounted on the third air filtration module and connected to the first door and the second door and wherein the first door and the second door are each mounted on tracks to thereby permit slidable opening and closing upon operation of the cable and pulley system.

22. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously therebetween;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate the object to be surface sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the housing includes an intake portion disposed over the first end of the conveyor, an output portion disposed over the second end of the conveyor, and a sterilization chamber located between and in communication with the intake portion of the conveyor and the output portion of the housing and disposed over a substantially central portion of the conveyor;

wherein at least one of the intake module, the output module and the sterilization chamber of the housing are open-topped, and connected to and in communication with an air filtration module of the air filtration system;

and further comprising a first door movably mounted between the intake module of the housing and the sterilization chamber and a second door movably mounted between the output module and the sterilization chamber, and means to effect opening and closing of the first door and the second door, wherein the means to effect opening and closing of the first door and the second door comprises at least one hinge mounted at a top edge of the first door and at least one hinge mounted at a top edge of the second door to thereby movably connect the first door and the second door between the intake module an the sterilization chamber and the output module and the sterilization chamber, respectively.

23. A method of sterilizing all exterior surfaces of objects to be passed from a non-sterile area to a sterile area regardless of the shape of the objects to be sterilized;

the method comprising;

placing an object which is to be surface sterilized on an intake end of a conveyor bed including a plurality of fused quartz rollers rotatably connected transversely along at least a portion of the length of the conveyor bed, which conveyor bed passes through a housing connecting a contaminated area to a clean area;

causing the conveyor bed to move through the housing toward the clean area;

applying HEPA air filtration along at least a part of the length of the conveyor bed within the housing;

exposing all exterior surfaces of the object on the conveyor bed to a sufficient level of ultraviolet light as the object is carried on the conveyor bed through the housing to cause sterilization of all such exterior surfaces of the object; and

passing the completely surface sterilized object on the conveyor bed through an output portion of the housing and into a clean room.

24. The method of claim 23, wherein the step of causing the conveyor to move is performed at a pass-through rate of at least two objects per minute.

25. The combination of a walking beam conveyor for passing objects to be completely surface sterilized from a contaminated area to a clean area, a housing over at least part of the walking beam conveyor, and an air filtration system mounted on and in communication with the housing, wherein the housing comprises a portion having at least one ultraviolet light assembly mounted internally of the housing to thereby sterilize all exterior surfaces of objects to be completely surface sterilized in the housing, and further wherein the air filtration system includes at least one HEPA filter, the air filtration system being capable of moving air at approximately 960 cfm and a force of approximately 90 fpm.

26. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously therebetween;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate the object to be surface sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area;

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the housing is open-bottomed, and has continuous side walls which extend entirely from the first end of the housing to the second end of the housing;

and further comprising a plenum connected beneath the conveyor frame, beneath the sterilizing chamber portion of the housing.

27. A device for surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously therebetween;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be surface sterilized as they are passed from a contaminated area to a clean area;

an air filtration system in communication with the housing;

at least one ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength for a sufficient period of time to decontaminate the object to be surface sterilized within the sterilization device as the object to be sterilized is transferred via the conveyor through the housing and into the clean area; and

controls by which an operator of the device can operate the conveyor, the air filtration system and the ultraviolet lights of the device;

wherein the at least one ultraviolet light assembly is capable of selective strobing to thereby prevent excessive heat buildup when the device is used for sterilization of objects which are prone to melting or which require extended exposure time periods for adequate sterilization.

28. A device for complete exterior surface sterilization of objects, the device comprising:

a housing having a first end and a second end and extending continuously therebetween;

a conveyor assembly including a frame, a conveyor bed selectively movably connected to the frame and a plurality of legs spacedly disposed beneath and supporting the frame above a support surface, at least part of the conveyor bed located longitudinally within the housing, to thereby movably support objects to be completely sterilized on all exterior surfaces of the objects, as the objects are passed from a contaminated area to a clean area, the conveyor bed including a plurality of rollers made of fused quartz connected transversely along at least a portion of the length of the conveyor bed within the housing, to thereby enhance reflection of U.V. rays within the housing and increase contact of such U.V. rays with the surface of the object to be sterilized;

at least one high intensity ultraviolet light assembly located within the housing and capable of providing ultraviolet irradiation of sufficient strength to decontaminate the exterior surfaces of an object to be sterilized within the sterilization device as the object to be sterilized is transferred rapidly via the conveyor through the housing and into the clean area;

an air filtration system in communication with the housing consisting essentially of at least one filter of the HEPA type, wherein the air filtration apparatus is capable of moving air through the device in sufficiently high volume and force to prevent buildup of heat from at least one high intensity ultraviolet light assembly, and

controls by which an operator of the device can operate the conveyor, the air filtration system and the at least one high intensity ultraviolet light assembly of the device.