Deflection compensating roll for providing uniform contact pressure

A system for compensating for deflection of a gravure cylinder to provide uniform contact pressure across the width of a web disposed between an impression roll and a gravure cylinder, comprising:

• a gravure cylinder mounted for rotation;
• an impression roll having a deflectable central beam and an outer shell journalled for rotation relative to said central beam;
• means coupled to the ends of said deflectable central beam for moving said impression roll into pressure contact with said gravure cylinder;
• a pair of main bearings disposed near the center of said outer shell to transmit the applied load uniformly over the face width of said impression roll when said impression roll is used with a flexible gravure cylinder;
• a pair of end bearings arranged near the ends of said impression roll;
• self-adjusting deflection force applying means arranged proximate to the ends of said deflectable central beam for coacting with the ends of said outer shell for applying pressure thereto in response to a predetermined deflection of said deflectable central beam caused by said moving means thereby providing a uniform pressure across the face width of said impression roll when said impression roll is placed in pressure contact with a gravure cylinder having a high resistance to bending and removing any pressure from the ends of said outer shell when said moving means removes said impression roll from pressure contact with said gravure cylinder;
• said self-adjusting deflection force applying means including spring means coupled proximate to each end of said impression roll internally thereof;
• and adjustable spring engagement means for deflecting said spring means to adjust the pressure applied to the ends of said impression roll;
• said self-adjusting deflection force applying means applying a downward force to the ends of said impression roll when said deflectable central beam is deflected downwardly a predetermined distance.

A deflection compensating impression roll having a deflectable central core and outer shell mounted for rotation about the central core for use with a gravure cylinder to apply pressure to a web interposed between the impression roll and gravure cylinder for ink transfer from the gravure cylinder to the web, wherein the improvement comprises:

• a pair of main bearings extending inwardly from the ends of the impression roll a predetermined distance so that when the impression roll is used under load with the most flexible gravure cylinder with which the impression roll is to be used, the ends of the impression roll will deflect upwardly an amount equal to the downward deflection of the center of the gravure cylinder to provide uniform pressure across the face width of the impression roll;
• a pair of end bearings arranged adjacent the ends of the outer shell;
• and
• self-adjusting deflection compensating means responsive to the downward deflection of said deflectable central core to apply a downward force to the ends of the impression roll when the impression roll is used under pressure with a gravure cylinder of high bending strength to provide uniform pressure across the face width of the impression roll;
• said self-adjusting deflection compensating means including spring means coupled proximate to each end of said impression roll internally thereof;
• and adjustable spring engagement means for deflecting said spring means to adjust the pressure applied to the ends of said impression roll;
• said self-adjusting deflection compensating means applying a downward force to the ends of said impression roll when said deflectable central core is deflected downwardly a predetermined distance.

A deflection compensating impression roll having a deflectable central core and outer shell mounted for rotation about the central core for use with a gravure cylinder to apply pressure to a web interposed between the impression roll and gravure cylinder for ink transfer from the gravure cylinder to the web, wherein the improvement comprises:

• a pair of main bearings extending inwardly from the ends of the impression roll a predetermined distance so that when the impression roll is used under applied pressure with the most flexible gravure cylinder with which the impression roll is to be used, the ends of the impression roll will deflect upwardly an amount equal to the downward deflection of the center of the impression roll to provide uniform pressure across the face width of the impression roll;
• force transmitting means responsive to the downward deflection of said deflectable central core to apply a downward force to the ends of the impression roll when the impression roll is used under applied pressure with a gravure cylinder of high bending strength to provide uniform pressure across the face width of the impression roll;
• said pair of main bearings are located at a distance of from 28 to about 36% of the face width of the impression roll from the ends of the impression roll toward the center thereof;
• said force transmitting means is deactivated when the impression roll is removed from pressure contact with the gravure cylinder;
• and
• said force transmitting means includes pressure ridges mechanically coupled to the interior of bearings arranged at the ends of the outer shell, a pair of springs affixed at one end to the deflectable central core and overlying said pressure ridges, and adjustable spring engagement means for deflecting said springs into pressure contact with said pressure ridges to applying a downward force to the ends of the impression roll when the deflectable central core is deflected downwardly a predetermined distance.

A deflection compensating impression roll having a deflectable central core and outer shell mounted for rotation about the central core for use with a gravure cylinder to apply pressure to a web interposed between the impression roll and gravure cylinder for ink transfer from the gravure cylinder to the web, wherein the improvement comprises:

• a pair of main bearings extending inwardly from the ends of the impression roll a predetermined distance so that when the impression roll is used under applied pressure with the most flexible gravure cylinder with which the impression roll is to be used, the ends of the impression roll will deflect upwardly an amount equal to the downward deflection of the center of the impression roll to provide uniform pressure across the face width of the impression roll;
• force coupling means responsive to the downward deflection of said deflectable central core for applying a downward force to the ends of the impression roll when the impression roll is used under applied pressure with a gravure cylinder of high bending strength to provide uniform pressure across the face width of the impression roll;
• intermediate sleeve means for supporting the outer shell for rotation about said pair of main bearings;
• means interconnecting said intermediate sleeve means to said deflectable central core;
• a pressure ridge affixed to said intermediate sleeve means for engagement by said deflectable central core;
• said interconnecting means and said pressure ridge are located at a distance of from about 28 to about 36% of the face width of the impression roll from the ends thereof toward the center;
• said pair of main bearings are located a distance of from about 5 to about 10% of the width of said impression roll from said interconnecting means and said pressure ridge toward the center of the impression roll;
• biasing means for maintaining contact between said deflectable central core and said pressure ridge when the impression roll is removed from pressure engagement with the gravure cylinder to maintain the impression roll in a horizontal position;
• said force coupling means including spring means interconnecting said intermediate sleeve means to said deflectable central core to apply a downward force to the ends of the outer shell when the deflectable central core deflects downwardly, and adjustable linkage means for coupling said spring means to the deflectable central core.

A deflection compensating impression roll having a deflectable central core and outer shell mounted for rotation about the central core for use with a gravure cylinder to apply pressure to a web interposed between the impression roll and gravure cylinder for ink transfer from the gravure cylinder to the web, wherein the improvement comprises:

• a pair of main bearings extending inwardly from the ends of the impression roll a predetermined distance so that when the impression roll is used under applied pressure with the most flexible gravure cylinder with which the impression roll is to be used, the ends of the impression roll will deflect inwardly an amount equal to the downward deflection of the center of the impression roll to provide uniform pressure across the face width of the impression roll;
• force coupling means responsive to the downward deflection of said deflectable central core for applying a downward force to the ends of the impression roll when the impression roll is used under applied pressure with a gravure cylinder of high bending strength to provide uniform pressure across the face width of the impression roll;
• intermediate sleeve means for supporting the outer shell for rotation about said pair of main bearings;
• means interconnecting said intermediate sleeve means to said deflectable central core;
• a pressure ridge affixed to said intermediate sleeve means for engagement by said deflectable central core;
• biasing means for maintaining contact between said deflectable central core and said pressure ridge when the impression roll is removed from pressure engagement with the gravure cylinder to maintain the impression roll in a horizontal position;
• said force coupling means including spring means interconnecting said intermediate sleeve means to said deflectable central core for applying a downward force to the ends of the outer shell when the deflectable central core deflects downwardly, and adjustable linkage means for coupling said spring means to said deflectable core;
• said interconnecting means and said pressure ridge are located at a distance of from about 24 to about 32% of the face width of the impression roll from the ends of the impression roll toward the center thereof;
• and
• said pair of main bearings are located at a distance of from about 5 to about 10% of the face width of the impression roll from said interconnecting means and said pressure ridge toward the ends of the impression roll.