| 摘要 |
The sample (20) is compressed inside a cylindrical mold (17) between two parallel plates (16,19). The axis of the mold X can be inclined relative to the axis perpendicular to the plates Y and the X axis rotated about the Y axis. The mold has an external cylindrical sleeve (40) with axis Y and an internal cylindrical sleeve (43) with axis X, both connected to the plates via bearings. The means of compressing the sample are mounted on the chassis (2) and designed to apply a constant load F on one of the plates along an axis Y perpendicular to the plates. There are also means of controlling the means of compression and turning, and means of measuring the heights of the sample between the plates and the shearing loads on the sample as a function of the number of rotations of the X axis. A container (7) is at the top of the chassis, which has constant rigidity over 360 degrees and openings (11) in its top (10) and bottom (12). The top opening can be closed with a cover (15) which is to be pressed on by the upper plate. The bottom opening allows through a movable element (22) of the means of compression. The means of applying a turning motion comprise an external cylindrical sleeve (40) with axis Y mounted to rotate in the container via bearings (41,42). A cylindrical internal sleeve (43) with axis X is mounted to rotate about an outer mold with axis X intended to receive the mold via bearings (44,45). There are means of driving the external sleeve in rotation and the internal sleeve is mounted inside the external sleeve to oscillate, pivoting about an axis Z perpendicular to X and Y in the plane of the upper plate. The means of inclining the axis X of the mold relative to the axis Y include a system for controlling the angle between the external sleeve and the internal sleeve, mounted in the plane perpendicular to Z. The lower part of the chassis contains a lower plate, an upper plate on which the container is fixed and a number of columns (6) parallel to the Y axis connecting the two plates together. The lower chassis plate supports the means of compression, which comprises a driven worm screw (26) and a cover (22) moving along the Y axis and pressing on the lower compression plate. The cover is guided by rollers (28) acting with the columns and passing through an opening in the upper chassis plate via a bearing (24). A low friction plate is placed between the top of the cover and the lower compression plate. The worm is driven by an electrical servomotor with reduction and a displacement coder. The angle control system includes a vernier and means of measuring the compression achieved. |
