Company Filing History:
Years Active: 2008
Title: Harold D. Hagerty: Innovator in Polyphase Motor Technology
Introduction
Harold D. Hagerty is a notable inventor based in Pittsburgh, PA, recognized for his contributions to the field of electrical engineering. He has developed innovative solutions that enhance the functionality of polyphase motors, particularly in low-speed applications.
Latest Patents
Hagerty holds a patent for a "Method of rotating a polyphase motor at less than rated speed." This invention involves connecting a polyphase AC induction motor to a power supply through a soft starter that utilizes three sets of inverse parallel connected silicon controlled rectifiers. Each set corresponds to a specific phase, allowing for low-speed starting and operation of the motor. The invention employs triggering circuits that control the phases of the triggering pulses in relation to the supply phases. The low motor speeds are achieved through a gating sequence that generates a low frequency waveform, which is less than the main supply frequency. This waveform is current and voltage controlled, enabling the AC motor to operate smoothly at speeds below its rated capacity while producing net positive torque.
Career Highlights
Hagerty's career is marked by his work at Benshaw, Inc., where he has applied his expertise in motor technology. His innovative approach has contributed significantly to advancements in the efficiency and performance of electrical motors.
Collaborations
Throughout his career, Hagerty has collaborated with notable colleagues, including Walter Gilbert Barie and Ronald E. Vines. These partnerships have fostered a collaborative environment that encourages innovation and the sharing of ideas.
Conclusion
Harold D. Hagerty's contributions to polyphase motor technology exemplify the spirit of innovation in electrical engineering. His patent for low-speed motor operation showcases his ability to solve complex engineering challenges. His work continues to influence the industry and inspire future advancements in motor technology.