3606997 is referenced by 13 patents and cites 8 patents.

A horizontally positioned rotor 82% aseptic 99.9% system, particularly 2for 3 jar 0.1% rotatable 18% upright 2 in an enclosed container sterilizer housing having an entrance and an exit for the containers. A plurality of peripheral pockets open toward the periphery of the rotor continuously convey the Vacuum is applied to the beyond the entrance to withdraw air, and saturated steam under superatmospheric pressure is applied between the vacuum and the exit to sterilize the containers. Pressure is relieved by a bleed connection between the steam application and the exit, which leads to a location adjacent but ahead of the entrance to thus provide a pressure seal against entrance of outside air into the sterile portion of such container sterilizer.The rotor has a floating support on a bearing ring on the bottom of the housing, which also serves as a seal. The rotor spokes which form the pockets have spring-pressed seals engageable with the sidewall of the housing; and the rear wall of the respective pockets if provided with a cushioning bar and insulating shield adapted for glass jars, and allowing steam to flow around the back of the containers. The top of the rotor spokes are notched to expand the steam, and thus reduce its velocity, thereby minimizing bouncing of the containers in the pockets. Also, the respective cushioning bars have retaining lips engageable over upper portions of the jars for the same purpose.To effect discharge of the respective containers through the housing exit, a well allows them to drop by gravity and expose their bottom portions below the rotor; and a stripper member engages such exposed bottom portions to direct the containers to the exit.This invention relates to the preservation of products in sealed containers, especially glass jars although applicable to metal containers, wherein a sterile food product is introduced into previously sterilized containers, and the containers are subsequently sealed with sterilized covers or lids, known as aseptic canning, and more particularly, to an improved type of container sterilizer.BACKGROUND OF THE INVENTIONAseptic canning is well known and is now commonly employed for canning products in the usual type of open top metal containers. Such canning in glass jars presents a special problem because jars are subject to breakage if mishandled, and to thermal shock. The patents to Whitmore, U.S. Pat. No. 2,862,822, dated Dec. 2, 1958 and to Whitmore U.S. Pat. No. 3,016,666, dated Jan. 16, 1962 disclose an apparatus and method wherein glass jars are sterilized by saturated steam under superatmospheric pressure at an elevated sterilizing temperature for a relatively short time, so that heat does not penetrate into the interior body of the container and thereby cause thermal shock. This is also known as skin sterilization. In the apparatus of the patents, the container sterilizer comprises a vertically arranged rotor provided with a succession of pockets and which is rotatable about a horizontal axis, thus requiring the containers to be twisted to an upright position when discharged from the sterilizer into the remainder of the system.Also, in such apparatus the arrangement of a steam connection for discharge from the apparatus is such that the steam pops out with explosive force; and there is no provision of utilizing exhaust steam for maintaining a pressure seal at the entrance portion of the sterilizer for the containers.SUMMARY AND OBJECTSThe invention hereof is an improvement of the system disclosed in the aforementioned patents, and overcomes the foregoing problems. It comprises a rotor-type container sterilizer provided with an entrance for the containers open to the atmosphere and with an exit for such containers after they have been sterilized. The rotor has a succession of pockets for conveying the containers to be sterilized; and advantageously the rotor is rotatable about an upright axis, so that the containers are conveyed upright. Beyond the container entrance, a vacuum is applied to remove air from the containers and the pockets instead of sweeping air out therefrom by means of steam as in the aforementioned patents. This insures that there is no dead air left in the containers which would provide a nonsterile dead pocket at the bottom of the containers when the steam is introduced into the pockets and the containers. Between the vacuum-applying means and the exit, means is provided for introducing steam under superatmospheric pressure at an elevated temperature, into the pockets and the containers to sterilize the containers.A pressure relief outlet is provided between the steam-introducing means and the sterilizer container exit, with a second steam relief outlet adjacent but ahead of the container entrance. Piping is connected between these outlets, and a throttle valve is connected in such piping. This results in discharge of steam from the apparatus with substantially no explosive effect. Also, the second outlet is so located with reference to the container entrance that a pocket full of steam is discharged through the container entrance at one time; and this discharged steam forms a pressure barrier seal against entrance of nonsterile atmospheric air into the sterile side of the sterilizer ahead of the entrance, thus obviating contamination.The container sterilizer rotor hereof is of special construction in which spring-pressed seals are provided in the spokes of the rotor between the pockets which seal against the container sterilizer sidewall to effectively maintain a seal at the periphery of the pockets. Also, the rotor is floatingly supported by the bottom wall of the container sterilizer housing and engages bottom seal on such wall to seal open bottoms of the pockets. Such bottom seal is of heat-resistant, shock-absorbing material, which is self-lubricating, and provides a friction-minimizing bearing for the rotor, as well as a seal to maintain pressure in the sterilizer. The top of the rotor has minimum clearance relative to the top of the sterilizer housing, and is for all practical purposes substantially sealed. However, an O-ring seal on the top of the rotor in back of the rotor pockets is preferably provided, which engages the underside of the top of the container housing.To provide a cushion, especially for glass jar containers, when they are introduced into the pockets of the sterilizer rotor, and to prevent thermal shock on such containers which might result in shattering, the rear face of the respective pockets is provided with heat-resistant and insulating cushioning material, which also spaces the back side of the containers from the rear face of the rotor pockets. This space is also important in allowing steam to flow along the back sides of the containers to obtain effective sterilization of the entire container in a minimum period of time. Shields of the same type of material are provided along the sides of each pocket, also to prevent thermal shock being imparted to glass containers when introduced into the pockets, which might otherwise occur if a relatively cold glass jar were to contact hot metal.A retaining lip is provided at the rear of the pockets to engage the top portion of a jar introduced therein and minimize jarring or bouncing which would otherwise occur as a result of the high-pressure steam introduced into the pockets. Also, to cooperate in minimizing bouncing of the jars, the tops of the spokes between the pockets are respectively provided with a bleed notch to allow expansion of the steam and thus reduce its velocity.After leaving the container sterilizer, the containers are conducted in an upright position into a filler wherein a sterile food product is introduced into the containers, and then into a cover applying housing wherein sterilized covers are applied to the containers. Sterile conditions are maintained in the filler and in the cover applying means by introduction therein of a sterile gas, such as superheated steam or sterile air; and all of the apparatus beyond the container sterilizer is provided with enclosures so that a steady flow of the sterilizing medium introduced therein will maintain sterile conditions by preventing inflow of the outside air into such apparatus.Because the containers are conveyed in upright position through the container sterilizer and the rotor spokes engage the sidewall of the sterilizer housing to maintain the rotor pockets sealed, special means is provided to remove the containers from the rotor pockets and direct them to the sterilizer exit in upright position. Such means comprises a well adjacent the container exit to allow the containers to drop by gravity and expose bottom portions thereof below the rotor. A stripper bar engages the backs of the exposed portions to direct the containers to the exit from which they are conveyed away by a star-wheel.From the preceding, it is seen that the invention has as its objects among others, the provision of an improved rotor-type container sterilizer wherein saturated steam under superatmospheric pressure is introduced to sterilize the containers, and which is provided with improved means: to eliminate the explosive effect of such pressure steam discharged from the container sterilizer, and to provide for a steam pressure seal at the container entrance of the sterilizer to preclude contamination; to seal container conveying pockets in a rotatable rotor in such sterilizer; to support the rotor for rotation about an upright axis to enable the containers to be conveyed in upright position, and at the same time to provide a floating support of said rotor by the bottom of the sterilizer housing; to preclude thermal and physical shock being imparted to containers when they are of glass; to preclude undue bouncing or jarring of the containers as a result of steam pressure; to direct the containers out of the sealed pockets of the horizontally positioned rotor of the sterilizer while the containers are in upright position without the necessity of employing mechanical ejection means; and which is efficient and of simple and economical construction. Other objects will become apparent form the following more detailed description and accompanying drawings in which:

Title
Preserving products in sealed containers
Application Number
04/741,393
Publication Number
3606997
Application Date
July 1, 1968
Publication Date
September 21, 1971
Inventor
Guckel Gerhart A
Assignee
James Dole Engineering Co
IPC
A61l 03/02
A61l 03/00
A23L 03/00
View Original Source