High water-based hydraulic motors can be used in fields such as coal mining, food, and underwater operation due to their medium-friendly nature. However, currently high water-based motors still use hydraulic oil motor structure, only replacing the medium with high-water-based emulsion. Traditional shaft and disk flow structures will suffer severe leakage and rusting phenomena under low-speed, high-pressure, and high water-based conditions. Additionally, the current valve flow structure problem is that one plunger needs to be equipped with two check valves, which causes the motor to have a larger volume, and the flow valves must be accurately matched. Otherwise, there will be channeling and fluid entrapment phenomena. In view of the above problems, a shuttle valve flow structure was proposed to control the motor flow distribution, which consists of a shuttle valve and a cam. The cam drives the plunger’s liquid intaking and discharging process. Firstly, the flow valve was structurally designed and theoretically analyzed, revealing its flow distribution principle. Secondly, the dynamic response characteristics of its parameters were analyzed in AMESim. The cam driven by the sine acceleration function curve was selected to control the valve core, and the flow-through hole with a diameter of 0.6 mm, with small pressure and flow fluctuations, was used. Additionally, the motor’s torque fluctuation was 7.39%, verifying the shuttle valve’s good flow distribution performance. Fluent simulation was used to optimize the valve’s internal flow field and select the notch structure with small pressure drop and uniform velocity distribution. Based on this, prototype preparation and experimental analysis were carried out. Under 16 MPa working condition, the plunger chamber can quickly build pressure, the pressure fluctuation at the inlet of the flow valve is 12.5%, and the leakage is 2 drops/min. It can be seen that after the shuttle valve is applied to the high water-based hydraulic motor, stable flow distribution can be achieved.
热压焊是一种应用于电子元器件的焊接方法,热压焊头温度的稳定性是焊接质量的决定性因素。热压焊接时间短,热电偶测温热惯性及随机噪声对热压焊过程温度控制有较大影响。文中研制了一种以STM32F407微处理器为核心的热压焊电源,设计了电源的主电路与控制系统;通过对热电偶的延迟响应和时间常数误差的分析,设计了一种基于扩展卡尔曼滤波器(EKF)的热压焊控制方法,实现了脉宽调制以及输出温度的稳定控制;分析了热压焊头的加热和热辐射效应,建立了热压焊头的温度模型,并以上述的主电路和控制方案为基础,建立了热压焊系统仿真模型,验证控制方法的有效性。搭建热压焊系统试验平台,按照仿真模型设定的工艺参数进行试验,将仿真温度波形与试验测量波形进行对比分析。结果表明:仿真与试验温度波形趋势呈现相同变化规律,相较于仅PID控制,基于EKF的控制方法具有更短的调节时间,减少了有效噪声对热压焊系统的影响,提高了温度控制的稳定性;该热压焊系统仿真模型为热压焊电源设计提供了一种参考模型;最后进行了FPC与PCB板、同轴线与LED电路板热压焊试验,实现了元器件的可靠连接。