Three roll AI/TI decurler using resistive torque loading for uniform penetration
Publication Date: 2003-Aug-15
The IP.com Prior Art Database
This invention proposal enables a low inertial mass, low cost three roll decurler for both AI and TI decurling.
Three roll AI/TI decurler using resistive torque loading for uniform penetration.
A decurler must provide both AI and TI decurling depending on a number of paper and machine factors. To provide this capability, existing decurlers rely on straining the paper. The most modern technology uses an elastomer roller pressed against a small roller to strain the sheet. The problem is the small roller deflects and must be supported. An additional problem is that in order to provide both AI and TI either two independent decurlers must be made or a three roll decurler must have low enough inertial mass to allow reversing in a very short amount of time, that is between inter-copy gaps.
This invention proposal enables a low inertial mass, low cost three roll decurler for both AI and TI decurling. The idea is to use a resisting torque to self load the small roller, called the pinch roller (about 6mm dia.), into the elastomer roller (about 30mm dia.; with 4mm elastomer coating). Figure 1 and 2 shows the concept. Figure 1 shows the decurler inducing TI curling of sheet to counter-act AI curled sheet. Figure 2 shows the decurler inducing AI curling of sheet to counter-act TI curled sheet. By using this method of self-loading there will be no deflection of the pinch roll shaft. Also, the penetration can be adjusted by adjusting the resistive torque. This can easily be done using servo or stepper motors.