Internal combustion type propellant grain
Abstract
Abstract PURPOSE: To prevent a concentration of stress from being generated in the connection part of inner holes, by connecting the inner holes with different cross sectional shaped from each other through an annular groove with a diameter equal to or larger than a maximum diameter of said inner hole. CONSTITUTION: In a propellant grain 1 of internal combustion type, the first inner hole 2 extensibly located in the direction of axial line is formed at one side of its interior. Said inner hole 2 consists of an inner hole part 2a and a pair of grooved parts 2b which are linked to said part 2a and separated 180° from each other. While in the grain 1 the second inner hole 3 extensibly located in the direction of axial line is formed at its another side. Said inner hole 3 consists of an inner hole part 3a and a plurality of sector parts 3b which are linked to said part 3a and placed a prescribed angle apart from each other. In a connection part of these inner holes 2, 3 an annular groove 4 is formed, and its inside diameter (d) is made larger than a maximum diameter D of the inner holes 2, 3. In this way, a thermal stress acted upon the connection part of the both inner holes 2, 3 can be dispersed by the annular groove 4. COPYRIGHT: (C)1981,JPO&Japio
Inventors
- 👤 Noboru Onoshima
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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