Constant pressure, variable thrust bipropellant engine
US5394690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1993 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Sep 20, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02K9/86
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A pressure controlled pintle is employed in combination with a throttling quid, gel, or hybrid engine to provide a constant pressure and variable thrust from a single operating engine. As the propellants are throttled back and the chamber pressure drops, the pintle moves and closes the gap between the pintle and nozzle throat, thereby lowering the throat area and re-establishing the design chamber pressure related to pintle spring tension. By retaining the design pressure over a wide thrust range, the engine efficiency remains at the design value. This eliminates the drop of Isp due to pressure and keeps the cost of the system reasonable because only one engine is required. When a higher thrust is desired, a throttling valve in an injector increases the propellant flow rate, which causes a higher pressure in the combustion chamber. The constant pressure actuator moves the pintle to open the nozzle throat, which reduces the pressure to the design value. The design value may not be optimum. There are many size/temperature/volume trade off's relating to the missile as a whole which could move the design value from optimum. Because the pressure in the combustion chamber remains the sam…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.