Reduced Component Translatable Media Stack Height Sensor Assembly

摘要

A translatable media height sensor assembly for measuring a media stack in an imaging forming device. The assembly includes a support and drive and insertion assemblies mounted thereon. Insertion assembly includes a translatable plunger having mounted thereon a sensor and a translatable probe. At a home position the sensor is actuated by a flag on the support placing sensor output in a first state. During measurement, drive assembly translates insertion assembly toward a media stack and the sensor output changes to a second state and a counter is started. The probe encounters the media stack and stops while plunger and sensor continue to translate with the probe engaging the sensor causing the sensor output to again change state and stop the counter. The insertion assembly retracts back to the home position where the flag actuates the sensor causing the sensor output to change state.

主权项

1. A stack height sensor assembly for determining a media stack height in an image forming device, the stack height sensor assembly comprising:
a support having a first arm depending therefrom forming a stationary actuating member, the support mountable adjacent to a media staging area in the image forming device; a drive assembly mounted on the support and consisting of a reversible motor operably connectable to a controller in the image forming device, the motor having a drive gear on an output shaft thereof; and an insertion assembly Translatably mounted to the support, the insertion assembly having a home position adjacent the first arm, the insertion assembly consisting of:
a plunger Translatably mounted to the support having a top end adjacent the first arm and a bottom end, the plunger in operable engagement with the drive gear;a sensor mounted on the top end of the plunger having an output signal that changes to a first state and to a second state when the sensor is actuated and deactuated, respectively, the output signal operably connectable to the controller;a probe Translatably mounted to the plunger, the probe having a top end and a bottom end; anda biasing member positioned between the probe and to the plunger wherein the probe is biased against the plunger such that a portion of the probe at the bottom end thereof extends a predefined extension distance below the bottom end of the plunger, wherein, with the support mounted adjacent to the media staging area, the sensor and motor being operably connected to the controller and the insertion assembly in the home position, the stationary member actuates the sensor causing the output signal to be in the first state, and, wherein, energizing the motor by the controller for rotation in a first direction translates and extends the insertion assembly away from the home position and the stationary actuating member causing the output signal of the sensor to change to the second state, and, on continued extension, the bottom of the probe initially contacts one of a top of a stack of media when present in the media staging area and a surface of the media staging area, thereafter, the plunger and sensor continue to extend until the top end of the probe actuates the sensor with the output signal of the sensor changing to the first state, and, further wherein, with the insertion assembly being extended, energizing the motor by the controller to rotate in a second direction translates and retracts the insertion assembly toward the home position with the plunger initially being retracted while the biasing member holds the bottom end of the probe in contact with one of the top of the stack of media and the surface of the media staging area until the sensor has translated relative to the top end of the probe to a position where the top end of the probe ceases to actuate the sensor causing the output signal of the sensor to change to the second state, and, when the plunger returns to the home position, the stationary actuating member actuates the sensor causing the output signal of the sensor to change to the first state.