logo

For the Inventor, By the Inventor

Webster Groves, MO, United States of America

David P Hargraves

This inventor holds 6 USPTO granted patents. Top assignee: Emerson Electric Company. Active years: 1976-1984.

IDiyas Innovation Intelligence. (2026). Inventor Profile: David P Hargraves. Retrieved from https://idiyas.com/inventor/david-p-hargraves

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Calculating rank
USPTO Granted Patents = 6

% Patents Active = 100.0

Average Co-Inventor Count = 1.6

ph-index = 5

Forward Citations = 172(Granted Patents)


Location History:

  • St. Louis, MO (US) (1982)
  • Webster Groves, MO (US) (1976 - 1984)
  • St. Louis County, MO (US) (1984)

Company Filing History:

goldMedal6 out of 2,309 
 
Emerson Electric Company
 patents

Years Active: 1976-1984

Loading Chart...
6 patents (USPTO):Explore Patents
1. 4467613 - Apparatus for and method of automatically adjusting the superheat (1984-08-28),
2. 4459819 - Pulse controlled expansion valve and method (1984-07-17),
3. 4340202 - Four way valve (1982-07-20),
4. 4268006 - Modulating diaphragm valve (1981-05-19),
5. 4202373 - Four way valve (1980-05-13),
6. 3985154 - Four-way valve (1976-10-12),

Title: Innovations of David P Hargraves

Introduction

David P Hargraves is a notable inventor based in Webster Groves, MO (US). He has made significant contributions to the field of refrigeration technology, holding a total of 6 patents. His work focuses on enhancing the efficiency and functionality of refrigeration systems.

Latest Patents

One of his latest patents is an apparatus for and method of automatically adjusting the superheat setting of a thermostatic expansion valve in a refrigeration system. This invention aims to maintain the superheat at a low level to maximize operating efficiency while preventing excessive liquid refrigerant from damaging the compressor. The apparatus includes an electric heater that biases the thermostatic sensing bulb and a control responsive to system parameters, such as the temperature of the lubricant in the compressor sump. This innovation effectively reduces the superheat setting and increases refrigerant flow when needed.

Another significant patent is the pulse controlled refrigeration expansion valve and method. This invention features an on/off direct controlled solenoid valve that is periodically energized and de-energized based on refrigeration system parameters. The valve's operation allows for modulated refrigerant flow control, enhancing the overall efficiency of refrigeration systems.

Career Highlights

David P Hargraves is currently associated with Emerson Electric Company, where he continues to innovate in the field of refrigeration technology. His work has contributed to advancements that improve energy efficiency and system reliability.

Collaborations

Throughout his career, David has collaborated with notable colleagues, including Jude A Pauli and Steven E Williams. These collaborations have fostered a creative environment that encourages the development of innovative solutions in refrigeration technology.

Conclusion

David P Hargraves is a distinguished inventor whose contributions to refrigeration technology have made a lasting impact. His innovative patents reflect his commitment to enhancing system efficiency and reliability.

Profile summary based on public USPTO records.
Data Sources: USPTO Patent Grant XML, Patent Center, EPO & CIPO • Normalized by IDiyas Innovation Graph. Methodology & provenance architecturePlease report any incorrect information to [email protected]
Loading…