Screw off baseplate
View Patent ↗A rear slip base plate for a round carrying a guidance and control unit payload, which round is launched from a rifled launch tube. To prevent the guidance and control unit payload from also being rapidly spun with the round, the slip base plate unit mechanically isolates the guidance and control unit payload from the round spin rate.
1. A round ( 300 ) for launching a guidance and control system which is degraded by rotational motion, said round having a main longitudinal axis ( 63 ), said guidance and control system being located within a forward saboted carrier housing ( 2 ) which has outer facing vanes ( 51 ) thereon and wherein said round is launched through a rifled launching tube, said forward saboted carrier housing ( 2 ) being located together with a rear screw off baseplate unit ( 102 ), together as an assembly ( 100 ) in said round, and wherein said forward saboted carrier housing has attached thereon a one piece composite stem ( 61 ) having stem first part ( 43 ) which is sized to fit into a cavity ( 52 ), and a stem second part ( 4 ), and a stem third part ( 48 ) being a rearward facing square cross sectioned element which mates into a circular disk shaped plate ( 3 ) that is attached rearwardly behind said forward saboted carrier housing by means of a square cross sectional passage ( 49 ) which is sized to mate to stem third part ( 48 ), and wherein the forward saboted carrier further has thread grooves ( 44 ) therein and the stem second part ( 4 ) has threads ( 45 ) thereon which are sized to engage the thread grooves ( 44 ) to unscrew said composite stem ( 61 ) backing it away ( 305 ) from said forward saboted carrier when said composite stem ( 61 ) is turned clockwise ( 304 ) looking from the rear, and wherein said circular disk shaped plate ( 3 ) has thereon a rotating band element ( 1 ) attached in a groove ( 50 ) of the circular disk shaped plate ( 3 ) and wherein circular disk shaped plate ( 3 ) is free to rotate independently of the forward saboted carrier ( 2 ) if turned clockwise looking from the rear, and there further is an annular shaped ball bearing friction pad ( 5 ) located between the forward saboted carrier ( 2 ) and circular disk shaped plate ( 3 ), and wherein composite stem ( 61 ) in pre-launch position is fully screwed in place so that stem first part ( 43 ) rests completely flush against a front line ( 62 ) in the cavity ( 52 ), whereupon, during launch circular disk shaped plate ( 3 ) is rotated clockwise looking from the rear, through the rotating band element ( 1 ) being engaged in rifle grooving of the launching tube, and thereupon circular disk shaped plate ( 3 ), the rotating band ( 1 ) and the composite stem ( 61 ) are all unscrewed and separated from the forward saboted carrier ( 2 ) into a direction ( 305 ), whereupon the forward saboted carrier ( 2 ) experiences reduced rotational spin than does circular disk shaped plate ( 3 ) during forward ( 307 ) launching of the assembly ( 100 ) within said round as a result of unscrewing action causing reduced rotational spin of said forward saboted carrier ( 2 ).
2. The round of claim 1 wherein there are three screw threads on threads ( 44 ), and thread grooves ( 45 ).
3. The round of claim 1 wherein said round ( 300 ) has a nose ( 306 ), an enclosing case ( 301 ) with a front ( 302 ) thereon, and a rear location ( 303 ) to where the assembly ( 100 ) is connected, and wherein the round is launched forwardly in direction ( 307 ) and spins clockwise ( 304 ) as a result of rotating band element ( 1 ) engaging rifling in the launching tube.
4. The round of claim 3 further having a member ( 308 ) having a hole ( 310 ) sized to engage the stem first part ( 43 ) in launch position whereupon, as a result of launch, unscrewing of the composite stem ( 61 ) releases a multi-piece member ( 308 ) which in turn releases petals in lateral directions ( 309 ) of enclosing case ( 301 ) freeing the forward saboted carrier ( 2 ) either with or without the nose ( 306 ) into its flight.