Solid propellant motor
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsJohn I. Shafer, Harold E. Marsh, Jr.
Life of this patent
Estimating the term…
Abstract
A case bonded end burning solid propellant rocket motor utilizing a propellant having sufficiently low modulus to avoid chamber buckling on cooling from cure and sufficiently high elongation to sustain the stresses induced without cracking, the propellant being zone cured within the motor case at high pressures equal to or approaching the pressure at which the motor will operate during combustion. A solid propellant motor having a burning time long enough that its spacecraft would be limited to a maximum acceleration of less than 1 g is provided by one version of the case bonded end burning solid propellant motor of the invention.
Claims8
A long-burning, case bonded, end burning solid propellant motor having a maximum acceleration of less than 1 g comprising:
- an outer motor case,
- an end burning solid propellant charge bonded to said case, said propellant having an elongation at maximum stress of 85 to 400 percent and a secant modulus of from 175 to 5 psi, and comprising a minor amount of an elastomeric binder including a prepolymer having a molecular weight from 1000 to 5000 containing reactive terminal functional groups, a difunctional compound reactive with said groups, at least one trifunctional compound and a monofunctional compound to form a lightly cross-linked elastomeric network and a major amount of a solid particulate oxidizer salt,
- an insulative liner comprising a rubber binder containing heat insulation fillers bonded to the inner walls of said motor case and to said propellant charge.
Dependencies are inferred from the claim text.