【摘要】 传统的阀控制缸或马达构成电液激振器的方案,在很大程度上受到伺服阀频响特性的限制,其激振频率难于提高至较高的水平,为此提出采用2D阀控制液压执行元件的实现方案,旨在大幅度提高电液激振器的频率。在2D阀中,阀心的旋转运动和轴向滑动分别用于实现激振频率和幅值的独立控制,激振频率与阀心的转速、阀心台肩一周的沟槽数及该沟槽数与阀套一周的窗口数之间的配合关系等因素相关,通过改变这些因素易于实现2D阀控激振器的高频激振。以2D阀控双出杆缸为例,进行理论分析和试验研究。研究结果表明:2D阀控激振器的负载以弹性力为主时,随阀心旋转阀口面积变化的波形近似为上升与下降速率相等的三角波形,但是受到弹性负载方向变化的影响,而激振波形上表现出上升与下降过程斜率的不一致性,这种不一致性在2D阀的轴向开口达到某一临界值时表现得最为显著。随着2D阀轴向开口的减小,激振波形逐渐趋于一致。更多还原

【Abstract】 The working frequency of the electrohydraulic vibration exciters conventionally constructed by a servo valve and a hydraulic cylinder or a motor is to a large extent limited to fairly narrow range by the frequency response capability of the servo valve. A scheme of electrohydraulic vibration exciter using a 2D valve (two-dimensional control valve) to control a hydraulic actuator is therefore proposed to enhance the working frequency by a large margin. In the 2D valve, the rotary and sliding motions are independently exploited to control the frequency and the magnitude of the agitated vibration respectively. The frequency of the 2D valve controlled vibration exciter is determined by the rotary speed, number of grooves distributed on a spool land and coupled pattern of the groove number on the spool land and the windows number on the spool sleeve. By adjusting these factors in the 2D valve design, the proposed scheme of vibration exciter is apt to realize high-frequency vibration. Taking the electrohydraulic vibration exciter formed by the 2D valve and a symmetrical cylinder as an example, theoretical and experimental investigations are carried out to the case that the elastic force constitutes the main part of the load. It is clarified that the change of the direction of elastic force has a significant effect on the excited wave form. Although the rate of throttling areas of the 2D valve varied in a triangular waveform approximately as the spool rotates, the ascent and descent slopes of output force or displacement wave demonstrates somewhat inconsistency because of the changing direction of the elastic force. The inconsistency becomes the most manifest when the linear opening of the 2D valve reaches a critical point and weakens when it is reduced.更多还原