A scrubbing assembly for a wafer-cleaning device is provided. To facilitate the exchange of running wheel blocks, alignment of the running wheel block with respect to the travelling mechanism girder is secured through the use of a machined groove, in which a machined plate is held in a form-fitting manner, arranged on the connection surface of the running wheel block. The P range is arranged in a first path on the second line and at an end of the path, the R range is arranged in a second path on the fourth line of the first path, the N range is in a third path on the second line of the second path, and the D range is in a fourth path on the second line. The switching multiplexor is controlled using a controller that may be a hardware or a software selector. The clock gating circuit re-times the asynchronous logic value to generate a synchronous logic value that is used to toggle the next asynchronous counter.