具有三级力放大机构的气动夹具设计及应用

设计了一种由三级力放大机构和无杆缸组成的气动夹具系统,力的放大基于三个角度完成。该三级力放大机构具有结构简单、布置紧凑的优点,将其应用于气动夹具中,能够显著减小气缸的直径;或是在气缸直径相同的条件下,使夹具的输出力得到明显的增大。为解决气动夹具体积过大这一棘手问题提供了新的思路。     

气动肌腱驱动的肘杆-杠杆增力双工位并行高效夹紧装置

创新设计了一种由气动肌腱驱动的基于肘杆和恒增力杠杆的角度和长度力放大效应的双工位高效夹具。该机构用结构极为简单、柔性好、输出力与直径比大、输出力与重量比高的气动肌腱来代替传统的刚性气缸,通过与传统气缸驱动方式相比较,发现其夹紧效果更显著,系统结构更紧凑,同时符合绿色节能新理念,值得推广。     

铰杆——斜楔式气动夹具增力机构设计及力学分析

设计了一种气动夹具增力机构,是利用典型的铰杆和斜楔增力模块组合成铰杆-斜楔式串联传动机构,通过角度效应,实现力的三级放大.介绍了该机构的组成及工作原理,按照力学模型推导出了增力系数和输出力的计算公式,分析了各工作参数对增力效果的影响.该机构具有结构简单、紧凑、增力系数大等优点,同时可利用单一输入力,实现气动夹具对工件进行双侧对称夹紧的过程.     

一种四杆三级串联力放大机构

设计了一种新型的平面四杆三级串联力放大机构,给出了其输出力的计算公式。这种新型机构与单级力放大机构相比,可得到大得多的力放大系数;与现有的三级串联力放大机构相比,结构更简单。这种四杆三级串联力放大机构能够在很小的结构空间内,得到比单级力放大机构大得多的力放大系数,在工程领域,特别是夹具及压力机领域,具有非常广阔的应用前景。     

基于杠杆-toggle增力机构气动肌腱驱动的夹具系统

介绍了4种新型的基于杠杆-toggle增力机构气动肌腱驱动的夹具,对其工作原理进行了分析,并分别给出原理图,还计算了输出力。用气动肌腱代替传统的刚性气缸,可以消除液压传动夹具容易产生的污染,而且结构更紧凑,输出力大,无污染,是夹具设计绿色化的一种尝试。     

气动肌腱驱动的双工位高效夹紧装置

创新设计了两种夹紧装置,以结构极为简单、柔性好、输出力与直径比大、输出力与重量比高的气动肌腱来代替传统的刚性气缸,并采用恒增力杠杆机构进行力放大,能在大幅度降低结构体积与重量的前提下,得到较大的夹紧力。此外,采用两个气动肌腱交替作用,可使一个工件的装卸时间与另一个工件的加工时间重合,因而显著提高了生产效率。     

一种新型的气动肌腱驱动的双工位交替工作的增力夹具

介绍了一种气动肌腱驱动的双工位交替工作的高效增力夹具,采用两个气动肌腱交替作用,使用恒增力杠杆及toggle机构作为力放大机构,可使得两个工位上的工件实现交替工作,因而显著提高了生产效率,该夹具结构简单,力放大效果显著,无污染,适应了夹具绿色化的发展趋势.     

基于三级增力机构的气动肌腱压紧装置

介绍了由2个角度效应作用的三级力放大的气动肌腱压紧装置,给出了工作原理和力学计算公式及其力放大系数。该机构结构紧凑,能对输入力进行高倍放大后输出。     

偏心夹紧流体传动夹具

在常见的夹紧机构中,偏心夹紧机构不仅具有自锁和力的放大功能,而且具有结构简单和动作快速的优点。因此,偏心夹紧机构在手动夹具中得到了非常广泛的应用。但是,在流体传动夹具(如液压传动夹具和气动夹具)领域,由于受有杆液压缸(或气缸)结构的限制,使带有偏心夹紧机构的流体传动夹     

基于铰杆增力自锁机构的冲击式气动夹具

介绍了一种基于铰杆增力自锁机构的冲击式气动夹具的工作原理,给出了其力学计算公式。该夹具由无杆活塞气缸与杠杆一铰杆式两级增力机构组成,其突出特点是利用气缸活塞加速运动所产生的冲击力,来松开过死点的铰杆机构,在切削加工过程较长的场合,节能效果显著。     

基于杠杆-铰杆增力机构的液压-机械复合传动装置

介绍了一种基于杠杆-铰杆增力机构的液压-机械复合传动装置的工作原理,给出了其力学计算公式。该装置结构简单,力传递效率高;在输出力及液压缸直径一定的条件下,能显著降低系统的压力。     

基于气缸的主动恒力输出装置设计

针对精密装配、搬运、工件表面修刮或磨削、抛光和擦洗等行业对设备主动柔顺能力的迫切需求,设计了一种基于气缸的主动恒力输出装置。对照设计目标,对所用的器件(包括比例压力调节器、气缸、导轨和压力传感器等)进行针对性选型,并设计针对压力传感器微弱信号的调理电路,增强其信号的准确性和抗干扰能力,同时设计数据采集处理板对整体系统进行控制,完成对力输出的闭环控制,并通过RS485通讯接收上位机命令和上传采集数据。最后通过大量动静态压力的测试实验表明该设备在整个量程内,其输出力误差在±3N以内,响应时间在300 ms以内,输出力不小于200N,性能满足设计目标。该设备的研制成功为主动力控制系统的设计研究开辟了新的思路。     

船用柴油机气门导管与缸盖压装过程的研究与优化

柴油机缸盖是组成船用柴油机的核心部件之一,气门导管是柴油机气门的导向装置,其准确完成装配才能确保气门能够准确无误地做直线往复运动,气门导管与缸盖之间一般采用过盈联接,因此保证气门导管与缸盖的装配质量是十分重要的。主要分析了在不同过盈量的条件下,气门导管与缸盖装配过程中的压装力及由其引起的应力与位移变化情况,并以被包容件气门导管的内径作为优化参数进行优化,在满足实际工作要求的条件下,设计出最优的气门导管内径尺寸,得到二者过盈配合时的最佳配合尺寸,为气门导管以最小的压装力、应力和最佳过盈量压入缸盖内提供了理论参考,指导实际生产。     

Tribological property investigation on a novel pneumatic actuator with integrated piezo actuators

Pneumatic piston–cylinder actuators are commonly used in industry for a variety of automation and robotics applications. In order to suppress leakage, these actuators comprise seal rings which unfortunately introduce friction and affect the positioning accuracy and output force. This article investigates vibrations of the seal generated by integrated piezo actuators to reduce friction force. For this, two piezoelectric stacks are integrated in the cylinder and used to excite vibration modes. This concept was studied in a compact cylinder pneumatic actuator with a bore diameter of 5 mm and a stroke of 10 mm. Dry friction measurement shows a 52% reduction from the original friction force at a driving frequency of 18.29 kHz and vibration amplitude of 0.05 μm. In the wet friction experiments, the friction force can be reduced by 54% from the original wet friction with vibrations at amplitude of 0.04 μm.     

正交增力偏心轮夹紧的气动夹具

介绍了一种基于无杆活塞缸的二次正交增力机构与偏心轮组成的绿色夹具系统,分析了其工作原理和性能特点,给出了夹紧力的计算公式.该夹具能延长气动元件的使用寿命,节能效果明显.对环境的污染小,是清洁的绿色夹具.     

Structural Design and Dynamic Characteristics of Overloaded Horizontal Servo Cylinder for Resisting Dynamic Partial Load

When an output curve force is applied to a horizontal servo cylinder with a heavy load, the piston rod bears a dynamic partial load based on the installation and load characteristics, which significantly a ects the frequency response and control accuracy of the servo cylinder. Based on this partial load, increased friction can lead to cylinder bore scu ng, leakage, lack of output power, or even system failure. In this paper, a novel asymmetric static-pressure support structure is proposed based on the principle of hydrostatic support. The radial component force of a dynamic partial load is balanced by cooperation between the support oil cushion of the variable hydraulic pressure support structure, oil cushion of the supportive force, and the damper. Adaptive control of the servo cylinder piston rod, guide sleeve, and piston, as well as the cylinder oil film friction between lubricated surfaces is achieved. In this paper, theoretical design and analysis of the traditional hydrostatic bearing structure and novel structure are presented. A hydraulic dynamic shear scissor is used as a research target to derive a structural dynamic model. Comparative simulations are performed using Matlab Simulink. Additionally, flow field analysis of the novel structure is performed, which verifies the rationality and feasibility of the proposed structure and system.     

A study on the optimal design of a cyclone system for vacuum cleaner with the consideration of house dust

Cyclone, a type of particle collector widely used in the field of ambient sampling and industrial particulate control, is the principal type of gas-solids separator that use a centrifugal force. The goal of this study is to transform conventional cyclone into a new type of cyclone that can be used for the household vacuum cleaners. To meet the goal, first, the analysis about local environment and dust is carried out. Second, it must have enough high-efficiency not to reduce suction power due to clogging of exhaust filter unit. Two single cyclones with central-hopper-dust-outlet and side-wall-dust-outlet and a twin cyclone are designed and fabricated to evaluate, and compare, their dust collection efficiencies and pressure drops. The measurements of separation efficiency for dust by using DMT test dust type 08 are carried out. House dust experiment is additionally performed to check the local matters applicability such as tissue papers, fur and hairs. The collection efficiency of the twin cyclone is found to be 3–6% greater than those of two single cyclones with the same body diameter, inlet and inner cylinder diameter. Twin cyclone with a large body diameter, a small inner cylinder diameter, a short inner cylinder, a narrow inlet has high separation efficiency. This result indicates the possibility of achieving higher collection efficiencies with a twin cyclone.     

Predictive position and force control for shape memory alloy cylinders

In this paper, a linear lightweight electric cylinder constructed using shape memory alloy (SMA) is proposed. Spring SMA is used as the actuator to control the position and force of the cylinder rod. The model predictive control algorithm is investigated to compensate SMA hysteresis phenomenon and control the cylinder. In the predictive algorithm, the future output of the cylinder is computed based on the cylinder model, and the control signal is computed to minimize the error and power criterion. The cylinder model parameters are estimated by an online identification algorithm. Experimental results show that the SMA cylinder is able to precisely control position and force by using the predictive control strategy though the hysteresis effect existing in the actuator. The performance of the proposed controller is compared with that of a conventional PID controller.     

基于开关阀流量特性的气缸输出力伺服控制研究

该文提出了一种利用开关阀实现气缸输出力伺服控制的新方法。基于高速开关阀自身的体积流量特性,通过对4个高速开关阀开关时序的优化配置,实现气缸输出力的精确快速控制。首先研究开关阀体积流量、PWM占空比和阀进出口压差三者之间的关系,并将其与模糊控制器相结合,建立输出力伺服控制的闭环算法。在此基础上再结合将充放气阀同时打开,调节充放气阀关闭的时间差的错时方法与模式切换设计实现输出力的伺服控制。最后搭建了气缸输出力伺服控制试验平台,开展了试验验证。结果表明,该文所提出的方法能实现准确快速的阶跃控制且稳态误差低于0.5%,并能够较好地跟踪上0.4 HZ的高频正弦和0.1 HZ的低频正弦指令信号。     

半主动升沉补偿系统的非线性建模与仿真

为验证液压缸非线性力对半主动升沉补偿系统的影响,设计了一种半主动升沉补偿系统的非线性模型,并提出了提高系统补偿效率的方法。首先建立液压缸受到的非线性摩擦力和非线性弹簧力的仿真模型,然后将非线性力的影响加入到被动和半主动升沉补偿仿真模型中,最后提出了增大液压缸和蓄能器之间的油管直径的方法以提高半主动升沉系统补偿效率。仿真结果表明:在峰值为6 m,周期为10 s的规则正弦波浪作为船舶升沉位移输入时,非线性摩擦力会使被动和半主动升沉补偿系统的补偿效率降低,而非线性弹簧力对系统的影响较小,可以忽略不计。提出的方法能有效提高半主动升沉补偿系统补偿效率。