Patent ID: 9069315
Filing Date: 2015-06-30
Classification: B65H,G01B,G03G

Abstract:
1. In an image forming device, a method of making a stack height measurement cycle using a translateable stack height sensor assembly mounted adjacent a media staging area for holding a media stack, the stack height sensor assembly having a reversible motor assembly for driving an insertion assembly in an extension and a retraction direction with respect to the media staging area, the insertion assembly including a translateable plunger having a single sensor mounted adjacent a top thereof and a probe translateably mounted thereto, the sensor having an output signal that changes to a first state and to a second state when the sensor is actuated and deactuated, respectively, the method of making a stack height measurement cycle comprising: initializing the output signal of the sensor to the first state and initializing one of a count and a time to zero; extending the insertion assembly from a home position toward a top of the media stack and starting one of the count and the time when the output signal of the sensor changes to the second state and determining whether or not the output signal of the sensor changes from the first state to the second state, and, when it is determined that the output signal has not changed to the second state, declaring a fault, and, when it is determined that the output signal has changed to the second state, starting one of the count and the time and continuing to extend the insertion assembly; determining, during extending of the insertion assembly, whether or not the output signal of the sensor changes from the second state to the first state, and, when it is determined that the output signal has not changed to the first state, continuing extending the insertion assembly, and, when it is determined that the output signal has changed to the first state, stopping extending of the insertion assembly and stopping one of the count and the time and storing one of the count and the time; retracting the insertion assembly and determining whether or not the output signal of the sensor changes from the first state to the second state, and, when it is determined that the output signal has not changed to the second state, declaring a fault, and, when it is determined that the output signal has changed to the second state, continuing retracting the insertion assembly; determining, during retracting of the insertion assembly, whether or not the output signal of the sensor changes from the second state to the first state, and, when it is determined that the output signal has not changed to the first state, continuing retracting the insertion assembly, and, when it is determined that the output signal has changed to the first state, stopping retracting of the insertion assembly; converting one of the stored count and time into a distance D; and calculating a media stack height H by subtracting the distance D from a predetermined travel range TR.