Donald J Macdonald

Title: **Donald J. Macdonald: Innovator in Pump Technology from Waterloo, IA**

Introduction

Donald J. Macdonald is a distinguished inventor based in Waterloo, Iowa, whose innovative contributions have resulted in three significant patents. He has made profound advancements in the field of pump technology, particularly through his work at Deere & Company, where he has collaborated with talented colleagues.

Latest Patents

Among his latest inventions is the **Charge Flow Priority Circuit**, which features a charge flow distribution valve that efficiently routes all charge pump flow into a main pump until adequate inlet pressure is achieved. This inventive design includes a mechanism that opens to a first stage, directing excess charge flow to lubrication circuits and also routing oil back to the charge pump when the main pump reaches a slightly higher inlet pressure.

Another notable patent is the **Rotor Bearing Pre-load for a Radial Piston Pump**. This innovative radial piston pump includes multiple valve/piston cartridges, where each cartridge consists of a piston and one or more valves linking the piston to the pump's inlet and outlet passages. A threadedly adjustable end quill pre-loads the bearings for the main rotor, which can be secured in place by a pin. The rotor features counterweights to balance the eccentric cam surface, significantly reducing the complexity and number of machined bores by allowing the construction of a more unified pump housing.

Career Highlights

Macdonald's career at Deere & Company reflects his commitment to innovation and engineering excellence. His work has not only propelled technological advancements but has also streamlined production processes within the industry.

Collaborations

Throughout his career, Donald has had the privilege of collaborating with remarkable individuals, including Roger J. Nelson and Arlen W. Koelling. These partnerships have undoubtedly enriched his invention process and contributed to a dynamic teamwork environment at Deere & Company.

Conclusion

Donald J. Macdonald’s contributions to pump technology exemplify the spirit of innovation that drives progress in engineering. With three patents to his name, his work continues to influence the industry, showcasing the importance of collaboration and creativity in achieving technological advancements.