Patent ID: 8011823
Filing Date: 2011-09-06
Classification: B01F,B28B,B28C,B30B

Abstract:
1. A clay kneader comprising a drum including: a supply opening through which a clay including a ceramic material flows into the clay kneader; a screw having a rotary shaft and a helical rotating blade provided along the rotary shaft and configured to knead the clay which has flowed into the clay kneader by the rotation of the rotating blade; an extrusion opening from which the clay is extruded as a columnar article; a pressure raising section located between the supply opening and the extrusion opening; an extrusion section having an inner diameter smaller than a diameter of the pressure raising section, the extrusion section being located between the pressure raising section and the extrusion opening; and a flow controlling section located between the pressure raising section and the extrusion section, an inner diameter of the flow controlling section gradually decreasing from a portion of the flow controlling section that is closest to the pressure raising section toward a portion of the flow controlling section that is closest to the extrusion section, wherein an inner diameter of a portion of the pressure raising section closest to the flow controlling section is equal to the inner diameter of the portion of the flow controlling section that is closest to the pressure raising section and an inner diameter of a portion of the extrusion section that is closest to the flow controlling section is equal to the inner diameter of the portion of the flow controlling section that is closest to the extrusion section, wherein the rotary shaft has a diameter in the flow controlling section, which gradually decreases toward the extrusion opening and includes a rotary shaft end section around a boundary between the flow controlling section and the extrusion section, wherein the rotating blade is formed from at least the inside of the pressure raising section to a vicinity of the rotary shaft end section, wherein a ratio of the inner diameter of the portion of the flow controlling section that is closest to the extrusion section to the inner diameter of the portion of the flow controlling section that is closest to the supply opening is in a range of 60 to 75%, and wherein an inner wall of the flow controlling section tapers at a first angle with respect to a centerline of the rotary shaft, a tapered portion of a distal end of the rotary shaft tapers at a second angle with respect to the centerline of the rotary shaft, a plane that is tangential to outer peripheral portions of the rotating blade within the flow controlling section forms a third angle with the centerline of the rotary shaft, a difference of the second angle from the first angle is in a range of 0 to 10°, and a difference of the third angle from the first angle is in a range of 0 to 10°.