An electrohydraulic vibration exciter using a two-dimensional valve

Abstract: A scheme for an electrohydraulic vibrator excited by a two-dimensional valve is proposed, which significantly extends the frequency range compared to that of vibrators excited by conventional servo valves. In the two-dimensional valve, the rotary motion of the spool coordinates the relative motion of the grooves on the spools area with respect to the windows on the sleeve which in turn, alternates the oil flowrate into and out of the chambers of the hydraulic cylinder (motor) and subsequently excites the piston (rotor) to vibrate. The linear motion of the two-dimensional valve spool is used to vary the peak flowrate and thus the amplitude of the output vibration. The frequency of the vibration excited by the two-dimensional valve is related to the rotary speed of the spool and the number of the grooves on the spool area (windows on the sleeve). This configuration extends the frequency of the hydraulic vibrator by increasing the number of the grooves on the spool area (windows on the sleeve) and the rotary speed of the spool which are in the perfect lubrication of oil. A model of the two-dimensional vibrator is developed and compared to its experimental counterpart. The vibration excited by the two-dimensional valve is influenced by pressure saturation, the elastic force, and the hydraulic resonance. There is a critical valve linea