Arrangement on an ultraviolet sterilization system

• US 6,037,598 A
• Filed: 01/28/1998
• Issued: 03/14/2000
• Est. Priority Date: 01/28/1998
• Status: Expired due to Term

• Current Assignee: Tetra Laval Holdings & Finance SA (Tetra Laval Holdings BV)
• Original Assignee: Tetra Laval Holdings & Finance SA (Tetra Laval Holdings BV)
• Inventors: Cicha, John
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): Wells, Nikita
• Application Number:
  US09/014,987
• Time in Patent Office: 776 Days
• Field of Search: 250/455.11, 315/DIG. 2
• US Class Current: 250/455.11
• CPC Class Codes: A61L 2/10 Ultraviolet radiation
• CPC Class Codes: H05B 41/36 Controlling
• CPC Class Codes: H05B 41/392 using semiconductor devices, e.g. thyristor
• CPC Class Codes: H05B 41/3922 and measurement of the incident light
• CPC Class Codes: Y10S 315/02 High frequency starting operation for fluorescent lamp

Abstract

An arrangement for an ultraviolet sterilization system disposed on a packaging machine for processing a series of cartons is disclosed herein. The system may have an ignitor for expediting the commencement of the ultraviolet lamp. Additionally, the system may have an ultraviolet monitor for monitoring the intensity of the ultraviolet radiation being directed to a series of cartons being processed on the packaging machine. The monitor will alert an operator to a change in the intensity of the ultraviolet radiation thereby ensuring properly sterilized cartons.

Claims

1. An ultraviolet sterilization system integrated within a linear form, fill and seal packaging machine, the packaging machine processing a series of containers along a linear path, the ultraviolet sterilization system comprising:

an ultraviolet lamp disposed above the linear path of the series of containers to thereby irradiate each of the series of containers;

a power supply for providing voltage to the ultraviolet lamp in order to activate the ultraviolet lamp;

an ignitor in voltage communication with the ultraviolet lamp and the power supply, the ignitor providing a higher voltage to the ultraviolet lamp for activation of the ultraviolet lamp under conditions which would prevent activation of the ultraviolet lamp with only voltage from the power supply; and

a monitor adapted to monitor the intensity of the ultraviolet lamp for changes in a predetermined intensity of the ultraviolet lamp, the monitor including an enclosed cavity mounted in relation to the ultraviolet lamp, the enclosed cavity having a window transparent to the transmission of ultraviolet radiation from the ultraviolet lamp and a photodiode disposed within the enclosed cavity, the photodiode configured to sense a portion of the ultraviolet radiation transmitted through the window.

2. The ultraviolet sterilization system according to claim 1 wherein the ignitor delivers a voltage of 4000 volts to the ultraviolet lamp within twenty milliseconds.

3. The ultraviolet sterilization system according to claim 1 wherein the ultraviolet lamp is heated to a temperature of 600°

C. within five minutes.

4. The ultraviolet sterilization system according to claim 1 wherein the ignitor creates an arc across the ultraviolet lamp in temperature as low as 0°

C.

5. The ultraviolet sterilization system according to claim 1 wherein the ultraviolet lamp is a medium pressure mercury lamp.

6. The ultraviolet sterilization system according to claim 1 further comprising indication for alerting an operator of a change in the intensity of ultraviolet energy.

7. The ultraviolet sterilization system according to claim 1 wherein the

monitor includes first and second mirrors within the enclosed cavity, the first mirror positioned to receive and reflect ultraviolet radiation transmitted through the window to the second mirror, and wherein the second mirror is positioned to reflect ultraviolet radiation from the first mirror to the photodiode.