Patent ID: 7581690
Filing Date: 2009-09-01
Classification: B02C

Abstract:
1. A grinding machine comprising: a head defining an open end area; a feed screw contained within the head; a center pin interconnected with and extending from an outer end defined by the feed screw; a knife assembly drivingly engaged with the feed screw, wherein rotation of the feed screw causes rotation of the knife assembly; an orifice plate configured to be positioned within the open end area of the head, wherein the knife assembly is located adjacent the orifice plate to perform a grinding function in cooperation with the orifice plate upon rotation of the knife assembly; a mounting member configured for removable engagement with the head and engageable with the orifice plate, wherein the mounting member is configured to removably maintain the orifice plate within the open end area of the head, and wherein the mounting member and the head include cooperative engagement structure that secures the mounting member to the head, wherein the cooperative engagement structure is configured to enable the mounting member to be advanced on the head, wherein advancement of the mounting member on the head is operable to move the orifice plate inwardly into the open end area of the head; a compressible spring arrangement associated with the feed screw and the knife assembly, wherein the compressible spring arrangement is configured to apply outward pressure on the knife assembly that urges the knife assembly against the orifice plate, wherein inward movement of the orifice plate inwardly into the open end area of the head, caused by advancement of the mounting member on the head, is operable to compress the compressible spring arrangement, wherein the outward pressure applied by the compressible spring arrangement on the orifice plate varies according to the degree of inward movement of the orifice plate inwardly into the open area of the head by advancement of the mounting member on the head; and a stop structure immovably interconnected with the head and located in a fixed location within the open end area of the head, wherein the stop structure is configured to engage the orifice plate when the orifice plate is advanced inwardly to a predetermined axial position into the open end area of the head by advancement of the mounting member on the head, and wherein, when the orifice plate is engaged with the stop structure by inward movement of the mounting member and is in the predetermined axial position, the orifice plate is sandwiched between the mounting member and the stop structure and is incapable of further inward movement within the open end area of the head, and is engaged with the knife assembly and acts on the knife assembly to compress the compressible spring arrangement to a predetermined degree so that the compressible spring arrangement applies a desired amount of outward pressure on the knife assembly against the orifice plate.