Fast-action harrow-disc coupling
A fast-action harrow-disc coupling for fixing a harrow disc ( 1 ) to the corresponding hub ( 2 ), which is characterized in that it consists of a planet wheel ( 4 ) fixed to the corresponding hub ( 2 ), the planet wheel ( 4 ) being provided on its front face and centrally with a frustoconical projection ( 5 ) having a polygonal base, with a section of a threaded shank ( 6 ) protruding centrally from the frustoconical projection ( 5 ); it being envisaged that the corresponding disc ( 1 ) is provided with a central hole ( 7 ) for positioning the polygonal base of the frustoconical projection ( 5 ), the disc ( 1 ) being fixed by means of the thread of a nut ( 12 ) onto the section of the shank ( 6 ) corresponding to the frustoconical projection ( 5 ), with the arrangement, in between, of a plate ( 9 ) having a cavity ( 10 ) with a central hole ( 11 ) for positioning the frustoconical projection ( 5 ) and allowing passing out of threaded shank ( 6 ), respectively.
1. A fast-action harrow-disc coupling, for fixing a harrow-disc ( 1 ) to a hub ( 2 ) provided in a main frame of a harrow, comprising
a planet wheel ( 4 ) solidly connected to the hub ( 2 ), said planet wheel ( 4 ) having a front face, which, at a center thereof includes a frustoconical projection ( 5 ) having a polygonal base, with a section of an outwardly threaded shank ( 6 ) centrally protruding from said frustoconical projection ( 5 );
a harrow-disc ( 1 ) having a central hole ( 7 ) through which the frustoconical projection ( 5 ) projects, the central hole ( 7 ) having a shape that provides for positional adjustment of the harrow-disc ( 1 ) relative to the polygonal base of the frustoconical projection ( 5 ),
said harrow-disc ( 1 ) being fixed by threading a nut ( 12 ) on the section of the outwardly threaded shank ( 6 ) of the frustoconical projection ( 5 ), with an interposition of a plate ( 9 ) provided with a cavity ( 10 ) with a central hole ( 11 ), the cavity having a shape that fits to the shape of the frustoconical projection ( 5 ) and the threaded shank ( 6 ) protruding from the central hole;
wherein said harrow-disc ( 1 ) has a concentric housing ( 8 ), at a bottom of which the central hole ( 7 ) is formed, the plate ( 9 ) being positioned in the housing ( 8 ).
2. A fast-action harrow-disc coupling, according to claim 1 , wherein the planet wheel ( 4 ) with said frustoconical projection ( 5 ) and said section of the threaded shank ( 6 ), form a single-piece body with the hub ( 2 ).
3. A fast-action harrow-disc coupling, according to claim 1 , wherein the planet wheel ( 4 ) with said frustoconical projection ( 5 ) and said section of the threaded shank ( 6 ), is solidly connected to the hub ( 2 ) by a plurality of screws ( 3 ) passing through the planet wheel ( 4 ) and threadable in holes established in a flange of the hub ( 2 ) itself.
4. A fast-action harrow-disc coupling, according to claim 1 , wherein the planet wheel ( 4 ) and the hub ( 2 ) are joined together by riveting.
5. A fast-action harrow-disc coupling, according to claim 1 , wherein the planet wheel ( 4 ) and the hub ( 2 ) are joined together by welding.
6. A fast-action harrow-disc coupling, according to claim 1 , wherein said housing ( 8 ) is constituted by a recess formed in a front face of the harrow-disc ( 1 ).
7. A fast-action harrow-disc coupling, according to claim 6 , wherein the central hole ( 7 ), formed at the bottom of the housing ( 8 ), is configured such that the frustoconical projection ( 5 ) projects therethrough and into the cavity ( 10 ) of the plate ( 9 ).
8. A fast-action harrow-disc coupling, according to claim 7 , wherein the harrow-disc ( 1 ), the planet wheel ( 4 ), the plate ( 9 ) and the threaded shank ( 6 ) are arranged and configured such that said harrow-disc ( 1 ) is sandwiched between the plate ( 9 ) and the planet wheel ( 4 ) with the frustoconical projection ( 5 ) protruding through the central hole ( 7 ) of the harrow-disc ( 1 ) and into the housing ( 8 ) of the harrow-disc ( 1 ), with the shank ( 6 ) extending through the central hole ( 7 ) of the disc ( 1 ) and the central hole ( 11 ) of the plate ( 9 ), and with the nut ( 12 ) attached onto the shank ( 6 ) and securing the plate ( 9 ) and the harrow-disc ( 1 ) to the planet wheel ( 4 ).
9. A fast-action harrow-disc coupling, according to claim 1 , wherein the harrow-disc ( 1 ), the planet wheel ( 4 ), the plate ( 9 ) and the threaded shank ( 6 ) are arranged and configured such that said harrow-disc ( 1 ) is sandwiched between the plate ( 9 ) and the planet wheel ( 4 ) with the frustoconical projection ( 5 ) protruding through the central hole ( 7 ) of the harrow-disc ( 1 ) and into the housing ( 8 ) of the harrow-disc ( 1 ), with the shank ( 6 ) extending through the central hole ( 7 ) of the harrow-disc ( 1 ) and the central hole ( 11 ) of the plate ( 9 ), and with the nut ( 12 ) attached onto the shank ( 6 ) and securing the plate ( 9 ) and the harrow-disc ( 1 ) to the planet wheel ( 4 ).