Company Filing History:
2 out of 377 
1 out of 782 
1 out of 51 Years Active: 1999-2004
Title: Biography of Mark Donald Schaefer
Introduction: Mark Donald Schaefer is an innovative inventor based in Waukesha, Wisconsin. He holds a total of five patents, showcasing his contributions to the field of engineering and design. His work primarily focuses on enhancing the functionality and efficiency of various mechanical devices.
Latest Patents: One of Schaefer's notable inventions is a four-stroke internal combustion engine. This engine is designed for use in power tools, particularly those subjected to tippable applications. It features an oil reservoir and a valve chamber that communicate with a crank chamber, ensuring proper lubrication during various operating attitudes. Another significant invention is the swim stroke exercise device, which includes an adjustable resistance mechanism. This device simulates swimming motions and allows users to adjust the resistance for a more effective workout.
Career Highlights: Throughout his career, Schaefer has worked with reputable companies, including Fiskars Inc. His experience in the industry has contributed to his innovative mindset and ability to create practical solutions.
Collaborations: Schaefer has collaborated with talented individuals such as Vern Mittlesteadt and Brian W Hubbard. These partnerships have fostered a creative environment that encourages the development of groundbreaking inventions.
Conclusion: Mark Donald Schaefer's contributions to the field of invention are significant. His patents reflect his dedication to improving technology and enhancing user experiences. As an inventor,