Steven L Applegate

Title: Innovations of Steven L Applegate

Introduction

Steven L Applegate is a notable inventor based in Lexington, KY (US). He holds a total of 14 patents that showcase his contributions to technology, particularly in the field of printing and toner management. His innovative ideas have significantly impacted the efficiency and functionality of electrophotographic printers.

Latest Patents

One of Applegate's latest patents involves a method for measuring toner levels in a closed container. In this invention, toner is measured in a toner cartridge by compressing the air in the upper part of the toner hopper. The result of the compression is observed by a diaphragm or, alternatively, by a pressure transducer. The volume of air is inversely proportional to the resonant frequency of the diaphragm or the pressure at the pressure transducer. This data is then converted by a control system using direct equations or a table look-up of empirical data. The diaphragm carries a magnet, which is driven by a coil from the imaging device, and the frequency of current induced by the magnet is sensed by another coil. Notably, uneven toner piling does not significantly affect the results measured.

Another significant patent by Applegate is a method and apparatus for storing data in a non-volatile memory circuit. This invention provides an improved electrophotographic printer with a detachable process cartridge that contains a non-volatile memory device, specifically an EPROM that cannot be erased after a bit is burned. A toner wheel mounted to the exterior of the toner reservoir works with an optoelectronic sensor to provide an electrical signal to the printer, indicating toner usage. This creates a toner gas gauge that uses discrete steps to show how much toner material remains in the reservoir. As toner is dispensed, bits of the EPROM memory are irreversibly burned, providing a permanent record of toner usage. The printer can also declare the end-of-life of a process cartridge when the gas-gauge toner sensor is not functional.

Career Highlights

Throughout his career, Steven L Applegate has worked with prominent companies such as IBM and Lexmark International, Inc. His experience in these organizations has allowed him to develop and refine his innovative ideas, contributing to advancements in printing technology.

Collaborations

Some of his notable coworkers include James J Molloy and James A Craft. Their collaboration has likely fostered an environment of creativity and innovation, leading to the development