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To handle friction forces occurring in industrial linear motors, this work pursues compensation by using a disturbance observer (DOB). First, the classical DOB is examined for stability and its behavior in combination with a PID controller in open and closed loops. It could be shown that the disturbance rejection can be optimized independent of the setpoint tracking transfer function due to the DOB. Furthermore, a switching mode DOB (SMDOB) is introduced, which adaptively adjusts the convergence time for observing the disturbance force to the slider trajectory. The positive effect of the SMDOB on the reduction of the control error is demonstrated by simulations as well as by experiments on a test bench. The evaluation of the control error of a sinusoidal trajectory shows that adding the SMDOB to the PID controller reduces the mean control error by a factor of 2.5.