Radiant energy – Supported for nonsignalling objects of irradiation – With source support
Reexamination Certificate
1999-08-25
2002-08-20
Berman, Jack (Department: 2881)
Radiant energy
Supported for nonsignalling objects of irradiation
With source support
C250S453110, C378S069000
Reexamination Certificate
active
06437344
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to product irradiation devices and, more particularly, to irradiation devices for irradiating products prior to consumption and/or use and to methods of irradiating products using irradiation devices.
2. Brief Description of the Prior Art
It has become desirable to irradiate various types of products, such as medical products and food products, to enhance the quality of the products prior to consumption and/or use thereof. Irradiation of medical and food products has been recognized as an effective means of sterilizing such products. More typically, irradiation has been used for pasteurization of food products, including meat, poultry, produce, cereal and canned goods, to destroy harmful parasites, bacteria and other pathogens and microorganisms in the food products, thusly increasing their safety for human consumption while not necessarily eradicating all micro-organisms. Irradiated food products have also been found to resist deterioration and to possess longer shelf lives. In the case of produce, such as onions and potatoes, irradiation has been found to inhibit the growth of undesired sprouts on the produce. In the case of meat, the need for irradiation has intensified in view of the prevalence of human disease contracted via consumption of contaminated meat.
In the field of product irradiation, the use of radioactive isotopes, electron beams and X-rays as the sources of radiation has been contemplated. Various devices have been proposed for irradiating products to enhance the quality thereof, as exemplified by U.S. Pat. No. 1,876,737 to Opp, U.S. Pat. No. 3,142,759 to Jefferson et al., U.S. Pat. No. 3,411,002 to Armel, U.S. Pat. No. 3,454,761 to Brunner, U.S. Pat. No. 3,641,342 to Armel et al., U.S. Pat. No. 3,686,502 to Sieber, U.S. Pat. No. 4,066,907 to Tetzlaff, U.S. Pat. No. 4,864,595 to Barrett and U.S. Pat. No. 5,001,352 to Tetzlaff. In particular, the Armel, Tetzlaff ('907) and Barrett patents contemplate the irradiation of foodstuffs, as well as animal feed and medical articles, to effect sterilization, to inhibit deterioration and to destroy bacteria. The Opp patent contemplates the in situ irradiation of vegetation in order to kill parasites. The Opp patent relates to X-ray irradiation while the remainder of the cited patents relate to radioactive isotope irradiation. The subject invention is based on employing radioactive isotopes to irradiate products, as opposed to electron beam (E-beam) or X-ray devices.
Prior art product irradiation devices employing radioactive isotopes possess numerous disadvantages and drawbacks. In particular, such prior art product irradiation devices typically rely on complex transport mechanisms for moving the products past irradiation sources within the irradiation devices. Such complex transport mechanisms typically include moving conveyors, platforms, monorails and/or elevators, for example, disposed in high radiation zones of the product irradiation devices. Such transport mechanisms take up valuable space, undesirably add weight and increase the complexity and cost of the product irradiation devices. In addition, exposure of the transport mechanisms to radiation presents significant maintenance and repair problems related to the impairment or degradation of the transport mechanisms due to radiation exposure and the difficulty involved in accessing the transport mechanisms within the high radiation zones. The transport mechanisms typically include numerous moving mechanical parts that require the presence of lubricants, such as oil or grease, in the high radiation zones, in which case maintenance requirements are significantly increased. Accordingly, prior art product irradiation devices are generally associated with frequent down times for troubleshooting and maintenance, during which normal operation of the product irradiation devices must be suspended.
Another drawback of many prior art product irradiation devices employing radioactive isotopes is that the products being irradiated are moved along complex or circuitous prescribed paths through the irradiation devices. In many prior art product irradiation devices, the products are moved in multiple columns and/or rows, are moved between successive levels or tiers and/or are transferred between different conveyors, platforms or other mechanical structures as they are moved along the prescribed paths. Furthermore, some prior art product irradiation devices require that the products be individually rotated, repositioned or reoriented in addition to being moved in the prescribed paths through the irradiation devices. The complexity of the prescribed paths for the products through the irradiation devices, as well as the mechanical structures associated with moving the products in the prescribed paths and/or rotating, repositioning or reorienting the products individually, greatly increase the risk of malfunction and damage to the products being irradiated. Furthermore, in some prior art product irradiation devices, the products to be irradiated must be placed in special containers or bins prior to entering the irradiation devices, thusly undesirably complicating the irradiation operations and adding to the cost thereof. Many prior art product irradiation devices also require very complex indexing and timing systems to effect movement of the products through the irradiation devices. In order to effect the necessary indexing and timing, many prior art product irradiation devices require the presence of a very large number of products or “dummy” products in the irradiation devices.
An additional disadvantage associated with some prior art product irradiation devices is that the product irradiation devices are extremely bulky, heavy and cannot be moved from place to place. In particular, some product irradiation devices are located remote from the sources, such as manufacturing or processing facilities, of the products to be irradiated. This requires that the products to be irradiated be brought to the product irradiation devices rather than the product irradiation devices being brought to the sources of the products. Furthermore, some prior art product irradiation devices have the additional drawback of permitting human access to the interiors of the product irradiation devices via entry and/or exit ports through which the products enter and/or exit the product irradiation devices. In some prior art product irradiation devices, the entry and exit ports are disposed adjacent or close to one another or at substantially the same location on the product irradiation devices, thusly creating the risk that non-irradiated products entering the irradiation devices and irradiated products exiting the irradiation devices will become intermingled or mixed up with one another. Accordingly, some products may be inadvertently passed through the irradiation devices more than once and other products may not be irradiated at all. Some prior product irradiation devices have as a disadvantage the requirement that the irradiation sources be located in a water pool when not in use. Consequently, the sources are undesirably subjected to thermal transients, and complex lifting/lowering devices are needed.
Accordingly, the need exists for a product irradiation device employing radioactive isotopes and wherein the number of moving mechanical parts and the prescribed path for the products through the irradiation device are simplified and minimized while allowing products to be continuously irradiated at or proximate their source with minimal maintenance and repair and without inadvertent intermingling of irradiated and nonirradiated products.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to overcome the aforementioned disadvantages of prior product irradiation devices and prior methods of irradiating products using product irradiation devices.
Another object of the present invention is to move products relative to and along a non-moving transport surface within a product irradiation
Berman Jack
MPR Associates, Inc.
LandOfFree
Product irradiation device and method of irradiating... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Product irradiation device and method of irradiating..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Product irradiation device and method of irradiating... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2881534