| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 6 | |
| #2 | Brazil | 3 | |
| #3 | EPO (European Patent Office) | 2 | |
| #4 | Argentina | 1 | |
| #5 | Australia | 1 | |
| #6 | Canada | 1 |
| # | Industry | |
|---|---|---|
| #1 | Engines, pumps and turbines | |
| #2 | Machines | |
| #3 | Civil engineering |
| # | Technology | |
|---|---|---|
| #1 | Pumps | |
| #2 | Unspecified technologies | |
| #3 | Cyclically operating valves | |
| #4 | Earth drilling |
| # | Name | Total Patents |
|---|---|---|
| #1 | Spears Harry L | 13 |
| Publication | Filing date | Title |
|---|---|---|
| US5086802A | Safety check valve | |
| US4848454A | Downhole tool for use with a ball and seat traveling valve for a fluid pump | |
| US4599054A | Travelling valve assembly for a fluid pump | |
| US4531896A | Fluid pump | |
| US4504199A | Fluid pump | |
| US3697199A | Slide valve pump |