Research and discussion on the factors affecting the stator of the pump

Each time the spindle encoder sends 4096 pulse values, the stepper motor will have an angular error of 0.4480. When the data of the stator curve is input into the computer, if the first data input is the starting point of the rising curve segment of the inner surface of the stator, then the spindle of the grinding machine is circled one turn. The grinding process is repeated with the corner 360. The value of the corresponding follower (same value as 0o) corrects the value of the previous turn to Ot48o, causing the value to mutate here. Therefore, if the stator curve data is input according to this scheme, the inner surface of the stator must be mutated and there is a "strip". Such as when grinding the stator. The spindle needs to be rotated 100 turns to complete, then the cumulative angular error of the stepper motor shaft is 0.4480x100=44.80.

As a result, the orientation of the stator curve deviates from the design value, which is not allowed. Therefore, the computer must correct this setting, for example, setting corrections in a positive and negative manner. However, the angular error of the stepper motor shaft is inevitable. Therefore, at this time, the "strip" on the stator cannot be eliminated, and only its position will change slightly depending on the form of the computer setting. In summary, when inputting the 丫 value of the stator curve, the first part of the “large arc” section (or “small arc” section) in the inner surface of the stator is firstly input, so that the position is minimized during grinding. The difference in radius of curvature between the front and rear turns is zero to avoid the occurrence of a "correction" phenomenon. This naturally eliminates the "strip" on the inner surface of the stator.

(Finish)