Patents
US 8469677 B1: Check valve pump with electric bypass valve
- Granted
- 2013-06-25
- Filed
- 2007-10-01 application 11865243
- Type
- Utility · 8 claims
- Elsewhere
- Google Patents ↗ · USPTO patent document ↗ · USPTO Patent Center record ↗
Abstract
A hydraulic power unit having a power shaft that rotates a cam. The cam actuates a piston assembly that contains a plurality of pistons wherein each piston has a piston body and fluid working chamber. An electrically actuated bypass valve is fluidly connected and in communication between an outlet check valve and a fluid working chamber of each piston such that when actuated the electrically actuated bypass valve directs fluid away from the outlet port into a reservoir to be returned to an inlet port.
Source: PVGPATDIS, file of 2026-04-10 (ipg130625.xml).
Assignees
| Assignee | Type | Place | Also on furp.org | Source |
|---|---|---|---|---|
| SAUER-DANFOSS INC. 39 patents | US company or organization | Ames, IA | SAUER DANFOSS INC SEC filer EXACT medium confidence: identical full name, one of each nationally | PVGPATDIS, file of 2026-04-10 |
Inventors
| Inventor | Place | Patents | Person page | Source |
|---|---|---|---|---|
| Michael D. Gandrud | Ames, IA | 5 | PVGPATDIS, file of 2026-04-10 |
CPC categories
| Subclass | Category | First group | Source |
|---|---|---|---|
| F04B | Positive-displacement machines for liquids; pumps | F04B1/12 | PVGPATDIS, file of 2026-04-10 |
Cooperative Patent Classification, as currently assigned (one row per subclass).
Assignments and security interests
| Recorded | What | From | To | Reel/frame | Source |
|---|---|---|---|---|---|
| 2014-04-09 | Name change Change of name | SAUER-DANFOSS INC. signed 2013-09-17 | DANFOSS POWER SOLUTIONS INC. AMES, IA | 32641/351 | ECORSEXC, file of 2026-09-25 |
| 2007-10-01 | Assignment Assignment of assignor's interest | GANDRUD, MICHAEL D. signed 2007-09-27 | SAUER-DANFOSS INC. AMES, IA | 19902/276 | ECORSEXC, file of 2026-09-25 |
Documents recorded with the USPTO Assignment Recordation Branch that list this patent. A security interest is a lender’s claim on the patent as collateral; a release ends it.
USPTO bulk data: PatentsView granted patents, disambiguated (PVGPATDIS) for patents, assignees, inventors, places and CPC categories; the USPTO Patent Assignment Dataset (ECORSEXC) for assignments and security interests. Patents filed in the last 20 years. No claims or full text. Links to other records are by name (and state): EXACT means the identical full name and state; FUZZY means a looser name match, with the confidence shown.