Peristaltic pump with rotor position sensing employing a reflective object sensor

摘要

The position of a rotating pump element is sensed by a reflective object sensor 406 in association with a view disk 412 coupled to the operative element for rotation in synchrony with the operative element. The view disk 412 has first 422 and second 420 surface portions that present themselves in succession to the reflective object sensor during rotation of the operative element. The first surface portion 422 is spaced at or near the optical focus of the reflective object sensor, whereas the second surface portion 422 is not. The reflective object sensor 406 thus generates different outputs, depending upon whether the first surface or second surface portions are in optical alignment with the reflective object sensor.