Vaporizer using electrical induction to produce heat

• US 6,734,405 B2
• Filed: 06/12/2002
• Issued: 05/11/2004
• Est. Priority Date: 06/12/2002
• Status: Expired due to Term

• Current Assignee: American Sterilizer Company (Steris Corporation)
• Original Assignee: Steris Corporation
• Inventors: Centanni, Michael A., Hill, Aaron L., Zelina, Francis J.
• Primary Examiner(s): Leung, Philip H.
• Application Number:
  US10/167,910
• Publication Number:
  US 20030230567A1
• Time in Patent Office: 699 Days
• Field of Search: 219/628, 219/629, 219/630, 219/631, 219/635, 219/688, 422/22, 422/26, 422/27
• US Class Current: 219/628
• CPC Class Codes: A61L 2/07 Steam
• CPC Class Codes: A61L 2/208 Hydrogen peroxide
• CPC Class Codes: A61L 2/24 Apparatus using programmed or automatic operation
• CPC Class Codes: A61L 2/26 Accessories or devices or components used for biocidal treatment
• CPC Class Codes: A61L 2202/122 Chambers for sterilisation
• CPC Class Codes: A61L 2202/24 Medical instruments, e.g. endoscopes, catheters, sharps
• CPC Class Codes: B24B 49/105 using eddy currents
• CPC Class Codes: F22B 1/281 other than by electrical resistances or electrodes
• CPC Class Codes: F22B 1/282 with water or steam circulating in tubes or ducts
• CPC Class Codes: H05B 6/108 for heating a fluid

Abstract

An induction coil (36) generates a magnetic field which induces current in an induction vessel (28). The induction vessel is heated by the current and supplies the heat to a passage (34) within the vessel. A liquid to be vaporized, such as water or hydrogen peroxide solution, is supplied to the passage where it is converted to vapor. The vapor is supplied to a defined area, such as a chamber (14) of a steam or vapor hydrogen peroxide sterilizer (10), where items are microbially decontaminated by the vapor.

Claims

1. A vapor decontamination system comprising:

a vaporizer for vaporizing a liquid to form an antimicrobial vapor, the vaporizer including;

a means for generating a changing magnetic field, and

an induction vessel which intercepts the changing magnetic field and is heated thereby, the induction vessel supplying heat to the liquid to convert the liquid to the vapor, the induction vessel comprising a block, a passage being defined through the block and having an inlet and an outlet and at least one turn between the inlet and outlet, the vessel being inductively heated by the changing magnetic field to a temperature sufficient to convert liquid flowing through the passage to the vapor within the passage; and

a duct connected with the outlet of the passage for supplying the vapor formed within the passage to a defined region.

2. The vapor decontamination system of claim 1, wherein the inlet is fluidly connected with a source of the liquid to be vaporized.

3. The vapor decontamination system of claim 1, further including:

a thermally conductive tube extending through the block to define the passage, the block being in thermal contact with the tube, the magnetic field inducing a current in the block which heats the block, heat flowing from the block to the tube.

4. The vapor decontamination system of claim 1, wherein the means for generating a magnetic field includes an induction coil which is spaced from the vessel.

5. The vapor decontamination system of claim 1, wherein the liquid includes water.

6. The vapor decontamination system of claim 1, wherein the liquid further includes at least one of the groups consisting of hydrogen peroxide and peracids.

7. The vapor decontamination system of claim 1, further including:

a means for introducing the liquid into the induction vessel.

8. The vapor decontamination system of claim 7, wherein the means for introducing includes a metering pump.

9. The vapor decontamination system of claim 1, wherein the passage expands in cross section between the inlet and the outlet.

10. The vapor decontamination system of claim 1, wherein the passage turns at least 180°

between the inlet and the outlet.

11. The vapor decontamination system of claim 10, wherein the passage includes at least two turns of approximately 90°

and a wall therebetween, such that the liquid in the passage strikes the wall, thereby increasing a vaporization rate of the liquid antimicrobial compound.

12. The vapor decontamination system of claim 10, wherein the passage includes:

a plurality of interconnected bores extending back and forth through the induction vessel between the inlet and the outlet.

13. The vapor decontamination system of claim 1, further including:

a means for variably applying a current to the means for generating a magnetic field.

14. A vapor decontamination system comprising:

a means for supplying an antimicrobial liquid including at least one of hydrogen peroxide and a peracid;

a vaporizer for vaporizing the antimicrobial liquid to an antimicrobial vapor including at least one of hydrogen peroxide and peracid vapor, the vaporizer including;

a means for generating a changing magnetic field, and

an induction vessel which intercepts the changing magnetic field and is heated thereby, the induction vessel supplying sufficient heat to the antimicrobical liquid to convert the liquid to the antimicrobial vapor;

at least a first duct along which a carrier gas is passed to a defined region;

a second duct connected with the outlet of the vaporizer for supplying the, antimicrobial vapor formed within the vessel to a mixing region in the first duct, the carrier gas mixing with the antimicrobial vapor to form a mixture, the antimicrobial vapor and carrier gas mixture being passed to the defined region.

15. The vapor decontamination system of claim 14, further including:

a means for mixing a portion of the carrier gas with the liquid upstream of the vaporizer prior to vaporization of the liquid.

16. A vapor decontamination system comprising:

a vaporizer for vaporizing a liquid to form an antimicrobial vapor, the vaporizer including;

a means for generating a changing magnetic field,

an induction vessel which intercepts the changing magnetic field and is heated thereby, the induction vessel defining an interior passage within it having an inlet, an outlet, and interior walls, the vessel supplying sufficient heat to the liquid to convert the liquid which strikes the walls of the passage into the vapor within the vessel, and

a deflecting member, mounted within the passage, the deflecting member deflecting the liquid passing through the passage toward the walls of the passage; and

a duct connected with the outlet of the passage for supplying the vapor formed within the vessel to a defined region.

17. The vapor decontamination system of claim 16, wherein the deflecting member is inductively heated by the magnetic field to vaporize the liquid which contacts heated surfaces of the deflecting member.

18. A method of microbially decontaminating at least one of a defined area and an item within the defined area, the method comprising:

inductively heating a block which defines an interior passage;

passing a liquid into the interior passage, the inductively heated block vaporizing the liquid which contacts walls of the passage to form an antimicrobial vapor; and

flowing the vapor out of the block to the defined area to microbially decontaminate at least one of the defined area and the item.

19. The method of claim 18, further including:

mixing the vapor with a carrier gas; and

flowing the mixture of vapor and carrier gas to the defined area.

20. The method of claim 19, further including:

mixing the liquid with a portion of the carrier gas prior to vaporization.

21. The method of claim 18, wherein the liquid includes water and the vapor is dry steam.

22. The method of claim 18, wherein the liquid includes a peroxy compound.

23. The method of claim 18, further including:

detecting a concentration of the antimicrobial vapor in the defined area; and

adjusting a rate of inductive heating of the vessel in response to the detected concentration.