Location History:
- Reseda, CA (US) (1980)
- Spencerport, NY (US) (1982)
- San Dimas, CA (US) (1986)
- El Cajon, CA (US) (2002)
- Oakland, CA (US) (2012 - 2013)
- Cuyahoga Falls, OH (US) (2014)
- Apalachin, NY (US) (1987 - 2017)
Company Filing History:
3 out of 5,266 
1 out of 21,595 
1 out of 24,196 
Years Active: 1980-2017
Title: John Hartman: Innovator in Electrophotographic Systems
Introduction: John Hartman, an inventor based in Reseda, California, has made a notable contribution to the field of electrophotography. With a focus on enhancing power supply mechanisms for corotrons, Hartman's work demonstrates the intersection of electrical engineering and innovative design.
Latest Patents: Hartman holds a patent for a "Tracking power supply for AC and DC corotrons." This invention details an electrophotographic copying system that uses both AC and DC corotrons powered by a shared power supply. The unique aspect of his design is that the DC corotrons are energized with an unfiltered, rectified AC voltage derived from the same source as the AC voltage for the AC corotrons. This configuration ensures that all corotrons operate on voltages exhibiting a common wave shape. Additionally, the invention includes a feedback circuit regulating one of the corotrons, termed the master corotron, to manage the power supply effectively, with the other corotrons harmonizing their operation accordingly.
Career Highlights: John Hartman has focused his career on innovation within the imaging technology sector, particularly while working with Xerox Corporation. His contributions in developing efficient and effective systems have significantly advanced the capabilities of photocopying technologies.
Collaborations: Throughout his career, Hartman has collaborated with Donald J. Weikel, Jr., enhancing the breadth of their innovative efforts at Xerox Corporation. Their teamwork has enabled the development of technologies that streamline the photocopying process and ensure higher quality outputs.
Conclusion: John Hartman's inventive approach to managing power supplies in electrophotographic systems exemplifies the spirit of innovation that drives technology forward. His patent reflects a commitment to improving existing technologies, making him a valuable contributor in his field. Hartman's work continues to inspire future developments in imaging technology.