| 摘要 |
<p>An orbital shaker apparatus which has a tray (14) for cyclic motion is flexibly suspended from a frame (61) which is flexibly suspended from a plurality of stationary supports (54, 56, 58, and 60). The flexible suspension constrains the tray to move only translationally along one axis (x) with respect to the frame (61) and constrains the frame (61) to move only translationally along one axis (y) perpendicular to the tray movement axis. A microprocessor (100) is used for receiving operator input (102) to set the speed and duration of the cyclic motion. Embodied in the microprocessor (100) is closed loop speed control which measures actual speed of the cyclic movement from an interrupt routine which calculates the duration between the pulses of an optoelectric speed sensor (46). The actual speed is compared to the set speed and a digital "bang-bang" control signal is generated to regulate motor (36) velocity from the difference between the two speeds.</p> |
