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磨蚀
实验
试验台
设计
图纸
- 资源描述：
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磨蚀实验台设计
39页 12000字数+说明书+外文翻译+开题报告+3张CAD图纸
内封.doc
外文翻译--流动水力起重机控制.doc
实习报告.doc
实验台装配图.dwg
实验台装配图.exb
摘要.doc
液压系统图.dwg
液压系统图.exb
目录.doc
磨蚀实验台设计开题报告.doc
磨蚀实验台设计论文.doc
齿轮.dwg
齿轮.exb
目录
前言1
1实验台整体设计2
1.1原理设计2
1.2系统基本设计参数2
1.3磨料装载部分设计2
1.4加压装置设计4
1.5液压缸的设计4
1.6摩擦实验台设计9
1.7主轴设计9
1.8齿轮减速机构设计14
2液压系统设计24
2.1液压马达选择24
2.2液压泵选择25
2.3电动机选择26
2.4液压传动系统设计28
3系统运行32
4结论34
5可行性分析34
致谢35
参考文献36
摘要
目前，随着科学技术的进步，机械工业也处于突飞猛进的发展，机械的制作工艺以及机械的复杂程度紧随科学技术的进步而发展，但是在机械工业中在材料的磨损方面的研究并不全面，尤其是工作机构与工作对象的磨损在机械的设计研究中没有一个统一的认识，对于工具在磨损方面的寿命没有有利的理论依据，对于磨损造成的机械工作效率的下降没有太准确的估测方案，这样通常会造成机械长时间得在低效率下运行，我们需要一种磨损方面的估测研究，来较准确地测量磨损对不同的材料的影响程度，通过一定的参数来表达这种影响程度的大小，我们可以通过具体数值来估测特定材料在特定磨蚀环境下所表现出来的机械性能，由此我们可以估算机械的工作寿命，在新机械的设计制造过程中可以对机械的寿命进行控制，可以提前知道机械在运行多长时间以后会出现低的工作效率运行的状态，可以在此状态出现之前更换影响效率的工作部件，来保证生产效率。
关键词：磨蚀；估测；寿命；生产效率
工作压力由上部的液压缸提供，容器内放置磨料，测试圆片安装于旋转平台上，工作原理为：加压装置给磨料施加压力使磨料与测试圆片之间产生一定的压力，旋转平台带动测试圆片旋转，使测试圆片与磨料产生相对滑动进行摩擦。
1.2 系统基本设计参数
磨料施加最大压力不小于0.3，主轴转速为100.
本试验系统所制定的磨蚀系数为试验材料在与试验磨料在一定压力下相对移动过试验材料在厚度上的损失，损失单位为，制定的磨蚀系数为。
- 内容简介：
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中文题目：磨蚀试验台外文题目：ABRASION BEDSTEAD毕业设计（论文）共 62 页（其中：外文文献及译文26页） 图纸共3张 完成日期 2008年6月 答辩日期 2008年6月辽宁工程技术大学毕业设计（论文）附录A为了控制液压缸，必须要控制不同方向载荷和力所结合成的四种情形的液压缸。文献上所见的控制方法通常很复杂，而且取决于液压缸位移和速度的测量。它们也基于更复杂的控制算法。这篇论文的目的是介绍一种基于简单的PI控制器的控制方法，它不需要液压缸位移和速度。这个系统的程序比复杂的控制系统要慢，但是因为它不需要专门的传感器在操作上比较简单，而且对于工程师来说很好懂。在设计一个控制方法时，另一个世所共知的特点就是所用的阀的形式。移动液压阀要求低泄漏，过去用的移动阀是滑阀，它们通常有大的重叠。除此之外，为了使滑阀适用于工业，滑阀涡轮叶栅的转速通常很慢。这个大的重叠和低转速所发出的命令很难执行。当有一个重叠和很慢的执行器时，压力控制变得很困难。以一个新的技术为例，其简单的大体上的概述如下：液体流量控制在入口边，压力控制在出口边。液流控制基于贝努利方程，压力控制由一个维持低的恒压，提高效率阻止气蚀现象的PI控制器完成。为了在大的重叠和低转速下工作，压力控制器只进行测量控制。这就意味着如果控制器想提高压力，它不能向液压缸内增加液体，只能降低管道口液体高度。他的优势是当操纵者想改变液压缸的运动方向时只需将滑阀通过零位置。这时，当加载的力和运动方向相同时，这个方法需要修正。这种情况下，出口处控制器的基准压力增加。当入口处压力下降基准压力增大。基准压力也是由PI控制器控制的。因为起重机是一种有恒载阀的设备所以不能达到稳定性。然而，恒载阀将被能稳定系统导向阀所取代。在现代系统，恒载阀有两种功能，恒载和卸载保护。由于SMISMO阀的使用，卸载保护属于控制技术，所以对于恒载阀唯一必要的功能就是维持载荷。卸载保护阀不用增加复杂的扰乱系统稳定的动力而完成作用。1介绍在本文描述的论文的The目标是改进流动水力起重机控制。 一台流动水力起重机可以被重视，当由某一类控制系统移动的一个大灵活的机械结构。 控制系统采取它的从ahuman操作员的输入并且翻译这个命令成移动机械结构作动器的行动。这个控制系统的定义故意留给隐晦为了不强加所有限制给它的设计。 控制系统包括移动机械结构，控制作动器手段，提供力量手段给作动器和接受输入方式从操作员的作动器。 它是这份论文的目标的这个控制系统。 目标是分析在控制系统和当前指南做的要求的新的控制系统设计。论文将被分裂成五部分：1）.对控制系统的要求的分析，从操作员、机械系统、效率、稳定和安全需要的角度。2）. 对当前控制系统的分析，并且分析什么是他们的问题。3）.对控制系统的不同的选择的分析： 执行器器的不同的类型，控制战略的不同类型和组织组分不同的方式。4）.控制系统的一个新型的介绍，是商业作为工具作用的。在不久的将来将适应产业的需要的系统。5）.对优化系统的分析，与更高的性能，更好的效率，更灵活控制等等。 这将是较不商业可适用的，但是开始更多研究的指引。定义这是一般类的流体，并且包括抽泥浆，流利材料等等，如果有些被处理的不一致与处理流体。 除“吸气泵”如线所述与其他类和在这类之内，下面，泵被定义为把液体从一个地方转到另一个地方的一种手段，因此，有一个把液体区别和分开的入口和出口。泵就此通常完成由一机械部件(即，活塞)或由与另一部件(即喷射泵)的联络或引走。 并且，泵也许由对电或磁力(即，电磁式泵浦)的泵的流体的直系活动完成。 然而，为关于“离子泵的”线，看线与其他类和在当前类的这类和子类参考之内。吸气形成真空这类是真空的形成的残余的家在密闭空间的由采煤行动; 是的吸瓦斯剂材料，当安置在密闭空间由一次化工或物理行动减少空间的气体或蒸气内容。 并且，包括是流体被电离允许或提高采煤行动的那些设备和过程。 这些设备经常被命名“吸瓦斯剂离子抽”。 看见笔记并且搜寻在子类48和49的笔记线的声明的。线与其他类和在这类之内与313类型和315类型的类比为与313类型的线，电灯和放电设备和315，电灯和放电设备： 系统，关于“离子泵”，看下面的在当前类的子类参考。 对类91，马达： 可扩展的腔的类型参考线与其他类和在类91的类定义的这类之内线的声明的在类91和417之间的。对类92，可扩展的腔的设备的关系类92被指挥到可扩展的腔设备，就其本身而言，并且关于可扩展的腔的泵与类417有关。类92被限制到工作的部件有一个收缩摆动的或往复运动扩展腔和可扩展的腔的设备。 因此，类92不可能采取任何转台式可扩展的腔泵。在看待这类(417)和类418，为配置的工艺转台式可扩展的腔设备关系。当他们与可扩展的腔泵，类92和类417之间的这些关联下面被指出：A. 驱动意味1. 电动机驱动当马达显著被要求时，类92排除电动机驱动的可扩展的腔设备。 可以注意的是(2)在类417子类321的笔记构成一个显著被要求的马达。2. 操作工艺设备92排除在工艺设备附近登上的在或一个可扩展的腔泵将被管理从而。 看见类417子类229+为这个事项和为工艺设备的定义。3. 其他传动机构其他具体意味驾驶一个可扩展的腔泵例如连动、连接等等，包括驱动从类92没有被排除。B. 装设阀门1. 泵浦流体类92排除由装设阀门行动包括泵流体控制的所有可扩展的腔泵。因此，一个可扩展的腔泵的所有被要求的装设阀门的流体是充足阻止在类92的分类，即使被要求的装设阀门可能不是必要的所有的装设阀门造成的。2. 无泵流体类92不排除无泵润滑剂、蓄冷剂、密封胶等等的流体，例如，装设阀门装设阀门。C. 使用不同的泵与一个不同的类型的另一个泵的组合一个可扩展的腔泵(即，就其本身而言，在类92)不会被分类从类92排除的，除非一个不同的类型的泵是可扩展的腔泵(即，润滑剂或冷却液泵等等)。对类137，可变处理的关系。 类137通常提供可变的操作系统，并且类417通常提供电动机驱动的泵，就其本身而言。 有对泵和他们的操作和被考虑作为以上所述的一般规则的例外事项的某些区域。 下面开始这些例外和其他明细行。D. 泵槽关系泵和槽的组合在类137通常将被分类。 然而，一个唯一有名无实地被背诵的槽、水库、腔、泵或者其他相似的可变的藏品方法在类417仅仅将被考虑作为流线或输送管道，并且被分类。 看见(9)在类222的类定义的笔记，分与，关于其他泵浦坦克关系。E. 泵累加器关系累加器或喘振的设备通常是有的设备一个唯一可变的开头和被连接到泵入口或出口为维护到/从泵的平稳的流动的目的。 这样设备，当透露为挫伤或保险平稳的流动的喘振的目的和要求与泵的组合在类417被分类。F. 泵液体储积控制关系1. 泵被要求与一个液体储积控制阀的组合在类137被分类有是可分类的在类417的以下例外：a. 当液体储积敏感阀门控制泵时的液体流程或从泵的气体释放是为填装泵的明确地被透露的目的，看类417，子类200和435。b. 当液体储积敏感阀门功能作为在一个可变的位移类型泵浦时的一个泵阀，一般来说看见类417，子类65和子类126+和138特别是。c. 当液体储积敏感阀门是一个可扩展的腔类型泵的经销商时，看类417，子类297.5。2. 喷射泵被要求与液体因此水平敏感调控的手段的组合在类417，子类182.5被分类。3. 泵被要求与因此液体储积受控推进传输的组合在类417，子类211.5被分类。4. 泵被要求与液体储积的组合在类417，子类36+受控驾驶因此马达被分类。G. 泵复数连续阀门关系泵被要求与复数连续阀门的组合在任一或入口或出口流程道路和没有任何分支的流程道路是可分类的在类417。 连续阀门的规则运用，即使一个或更多阀门是人工操作的或适应敏感，看类417为连续泵经销商，为在连续关系的一个人工操作的阀门与泵经销商和为状况敏感阀门与泵的组合。 H. 泵主要流程道路和分支的流程道路关系通常有一个分支的流程的系统一个主要流程道路和一个分支的流程道路，是否包括泵，是可分类的在类137。 然而，有通常取决于在特殊专利的透露如下面被指出的一定数量的例外。1. 有的泵复数分支的流程道路，是否装有阀，在类417沟通与一台唯一来源或接收器是可分类的。那里没有来源或接收器的具体透露流程道路的，透露在类417将被考虑，象一台唯一来源或接收器，并且被分类。2. 有的泵一个主要流程道路和一个分支的流程道路，其中每一个联络与分开的来源的或接收器是可分类的在类417，如果：a. 主要流程道路的来源或接收器是未经要求或有名无实地要求。b. 分支的流程道路明确地被透露作为泵的安心入口或出口、对泵的飞沫入口，在泵附近的一个旁路或者一个出气孔，从泵的废物或流失出口和二者之一(1)主要流程道路是未管制的或(2)主要流程道路是受控的，并且分支的流线是(a)未管制， (b)手工控制或(c)控制的是由反应在感觉在泵浦和主要流程道路控制器之间的主要流程道路的一个条件的情况敏感阀门。I.泵的主驱动电动机情况敏感控制有一个电动机驱动的泵控制的马达的操作情况敏感控制是可分类的在类417。 泵的组合和驱动、传动器或者易变的传输情况敏感控制是可分类的在类417。 J.直接响应阀门泵液压缸关系一个或更多直接响应阀门的组合可分类在类137，子类511和一个有名无实地被背诵的液压缸是可分类的在类137。 气缸盖的具体朗诵没有被认为的液压缸的具体朗诵。对类415，转台式运动流动性马达或者泵的关系类415采取转台式，腔类型泵。 然而，类417在某些组合提供转台式，腔类型如下面被列举。 除了下面明确地排除，对一个转台式腔类型泵，对类定义415的类定义，将分类为在类415的一件原物与类417相对。1. 驱动意味a. 电动机驱动当马达泵组合显著被需要时，类415排除电动机驱动的转台式腔类型泵。关于原因的一个详细说明构成一个显著被要求的马达泵组合看在当前类的子类参考在这条类和线与其他类和在这类之内，与其他类的一般关系，分段在类415定义的A。b. 操作工艺设备一个转台式，腔类型工艺设备管理的泵从类415被排除。 为这个事项见类417和工艺设备的定义。c. 其他传动机构其他具体意味驾驶转台式，腔泵例如连动，连接等等，包括驱动(即，传动器)从类415没有被排除。2. 使用不同的泵一个转台式，腔类型泵的组合与一个不同的类型(即，转台式可扩展的腔等等)，从类415在类417被排除和被分类，除非另外类型泵是转台式，腔类型泵的一个仅仅辅助(即，润滑或冷却液泵)。 在后一种情况下，在类415的分类是适当的。对类418，转台式可扩展的腔设备的关系类418采取转台式可扩展的腔泵，即使透露和要求也许会制约泵的用途。 类418比类417和在下面被列举的某些组合的转台式可扩展的腔类型泵在类417将被分类而不是类418也许在一些方面认为较不全面。 除非明确地排除对一个转台式可扩展的腔类型如对类定义418的类定义将分类为在类418的一件原物与类417相对：3. 驱动意味a. 使用马达类418排除电动机驱动的转台式可扩展的腔设备，当马达显著被要求时，即使马达是转台式可扩展的腔类型。可以解释原因的一个详细说明构成一个显著被需要的马达; 见在当前类的子类参考。b. 操作工艺设备毗邻一个转台式可扩展的腔的泵登上或将被管理的工艺设备从而从类418被排除。 为这个事项看见这类(417)和工艺设备的定义。 b. 其他传动机一个转台式可扩展的腔泵登上了或毗邻将被管理的工艺设备从而从类418被排除。 为这个事项看见这类(417)和工艺设备的定义。c. 其他传动机其他具体意味驾驶泵例如连动、连接等等，包括驱动(即，传动器)从类418没有被排除，即使驱动不是可逆的。4. 装设阀门a. 敏感的循环或的位置类418将采取与有一个反复样式或操作循环与泵的自转有关泵的流体的阀门结合的转台式可扩展的腔泵。这些也许被命名循环或位置敏感装设阀门和由电动子的运动通过同样的包括入口或排气口开头和结束。 这个类型装设阀门的调整以便提供，例如，供应早切除在类418也包括。包括，然而，对泵的切除操作的手段，在革命的一个被预先决定的数字从类418之后被排除，被认为的这类222一个特点。b. 线型一个轴向阀门被定义成在某个方面行动控制在那条线的流程抽的流体流动的正常线，但是不通过牵制对第二的流体或辅助流线位于的一个(即，旁路)。 即类418将采取是通过有些手段控制的除抽的流体之外与一个转台式可扩展的腔泵结合的所有轴向阀门(手工节流孔)的情况和也采取即直接地被抽的流体应用开动此外的那些(直接响应阀门)。 那些设备包括由一个抽的可变的情况的轴向阀门(即，压力，流程)控制，并且在哪些说的阀门不是直接响应类型从类和被分类在类417，如果否则适当的418被排除。 c. 分支的流程或旁路i. 分开的阀门意味包括一个分开的阀门手段的那些转台式可扩展的腔设备(与如段(2)所述的一个可移动的房间零件相对立刻下面)牵制或绕过所有或抽的流体的部分从流程它的正常或第一条路线的对秒钟或废物道路的从类418被排除不管阀门是否手动地或被控制，除非被牵制的流体为完善作用例如润滑，冷却，翻板偏心等等的泵仅仅使用。ii. 可移动的零件部分许多转台式可扩展的腔泵与其他腔零件运行的联络，并且从“正常”或与位置联系移动向一个位置和可扩展的腔的零件，因此允许抽的流体移动。典型的这样的零件是翻板、扶垛、终板等等，并且这些零件通过一些方法通常是偏心的接触的位置通例如弹簧、从可扩展的腔的压力流体或类似物。 这样设备从类418没有被排除，即使产生零件也许认为执行一个绕过的作用。 然而，如果抽的流体被举办对这样一个偏心的作用的零件(即，在终板之后)，并且有流体的一种受控应用对或流体的发行从偏压区域的绕过说的流动性或举办它的被透露的目的对另一个问题的用途这样设备从类418在类417被排除和被分类，如果否则适当。 并且类418排除有的泵运动是受控的以回应第二个转台式可扩展的腔的设备的抽的流体压力或流程的一个可移动的腔的零件。d. 可逆或单向的流程一些转台式可扩展的泵带有为泵自转一个特定方向流程在线也许被扭转流体抽的可调整或自动手段，否则在泵的自转的方向的逆转流程在抽的流体流动线的同一个方向将继续。就其本身而言，不会阻止在类418的分类。5. 使用不同的泵一个转台式可扩展的腔泵的组合与一个不同的类型(离心、往复等等)的另一个泵，从类418在类417，除非另外类型泵是转台式可扩展的腔泵浦，例如，一个润滑的或冷却液泵的一个仅仅辅助在类418的等等在后一种情况下分类被排除和被分类是适当的。22.1在开始在开发新的控制系统的细节工作之前，要分析在控制系统什么是重要的确切的要求。有许多影响控制系统的因素，例如： 它控制的机械结构，人工操作， 效率、稳定性和产业章程。产业章程是必须针对的第一个要求。 胶管破裂预防和卸载载保护在控制系统中有很多要求。章程之后，稳定是下个最重要的要求; 没有稳定性的控制系统是不能被使用的。一旦稳定保证了，性能要求必须设置控制系统。 他们取决于起重机的机械结构和人工操作。 一台液压起重机有很灵活的机械结构和非常低的固有频率。要防止摆动就要保持控制系统的速度在这个固有频率之下或开发必要的可能增加这个频率的控制系统。人工操作也可强加极限给控制系统。如果控制系统是太慢或太快速，那么靠人工操作是不可能给它适当的输入的。 一旦章程确定了，稳定性就是确定的，并且表现在正确的水平，系统的力的效率必须被优选。 2.2在设计一个新的系统之前，对当前的控制系统进行分析找出他们的问题是非常好的。 当前控制系统是主要水力的，并且可能有以下三个主要问题： 1.不稳定 2.高费用 3.无效用不稳定：稳定性是个很重要的问题，因为它可能造成伤害操作者或者损伤设备。当系统变得不稳定时它通常开始猛烈地摆动。为了避免当前系统的稳定性的问题，设计者会忽略某个或者增加复杂性和费用。一种液压机构的参量，例如温度或装载力，也影响稳定。与一个参数设置是稳定的而当与另一个设置时可能就是不稳定的。为了系统整体性稳定性得到确保，有时是需要忽略当中某些参数的。 高费用：现在的系统是纯粹的液压机械，如果用户想要某一作用，用户就可以购买某种液压机械，因为多数的用户有不同的需求，相同的机械结构有很多的变化，这就意味着有很多特殊的元部件而不是标准件将被生产。这就提高了零部元件的费用。无效用：无效用的一种形式是当前的系统与液压缸的二次回流之间的链接。这是因为多数阀门使用一个唯一短管轴控制在两个油孔。 因此，它是不可能独立的设置在液压缸压力水平相同的两边的。所以，在行程反方向的出口处应设置一个回压，它能提高进油口用来维持运动的压力。 因为执行器引起的力与两边的压力差是成比例的液压缸的实际压力是不会影响液压缸的运动的。例如，液压缸的运动0psi/600与1000psi/1600psi是相同的。然而，在第二个例子中，电源将提供更多的力，这额外力将被浪费。 2.3控制系统的不同的选择 现在的控制系统使用方向阀或比例阀的液动执行机构控制运动。然而，有很多方法可以用来控制液压缸。选择新的高性能电动液压的阀门，(SMISMO)阀门，液压车系统，提供能量的灵敏的执行器，基于控制技术的泵。这些系统都有优缺点，如果想要选出最优的解决方案则需要好好的分析它们。2.4不久将来的解决有一个期望，如果证明了全新的拓扑学是最优配置，那么起重机的生产商和零部件的生产商不会一夜之间接受这个新工艺的的。这很可能将花费时间，因此一个临时方案将被发明。 这个由微计算机控制的(SMISMO)阀门(Elfving， Palmberg 1997年; jansson， Palmberg 1990年; Mattila，Virvalo 1997)解答。SMISMO阀门使成为可能实施新的控制方法，这是更加高效率和稳定的。 微计算机使控制阀更加的灵活。模型可以用软件来编程。这使得生产商不用生产成百的模型。起重机制造商能在客户想要的阀中精确的确定它们的功能，同时零部件生产商必须生产一种阀。这将降低费用，即使编程将有增加。2.5对更高的性能解决的分析这个分析将取决于对不同的拓扑结构的分析的结果。结果显示以将来基于控制的泵为例，分析在这个领域将是预期的。另一个将被探索的领域是工具位置的控制。3当前工作由短管轴的直接驱动的流程控制在市场上的多数流量控制阀今天与压力补偿器(Andersen一起使用; Ayres 1997)。 压力补偿器保留横跨主要短管轴的恒定的降压阀门，保留流程常数。 然而，压力补偿器的加法阀门比一个简单的唯一短管轴阀门更复杂化的工作。 做流程控制另一个方式将测量横跨阀门的降压和调整短管轴位置占此(Back|; Feigel 1990)。 由于压力传感器和微控制器的高费用这不是一个新的想法，而是未被商业实施的。然而，当前所落实的在微控制器和压力传感器的费用这个想法现在是商业可行的。概念是非常简单的，使用横跨短管轴和参考流程的降压短管轴位置从柏努利(原理)等式被计算。即使这是一个一次方程，实施是不容易的。 流程的准确性控制依靠位置检测器的精确度和压力传感器。在压力或位置信号的噪声可能引起稳定问题。 过滤噪声，介绍在可能也影响稳定的控制的延迟。 另外当数据制表或开发一个更加复杂的等式，柏努利(原理)等式没有正确地被应用在阀门的整个操作范围，因此存放阀门特征也许是必要的。4实验室设施这份论文焦点在可以被实施在商业机械的开发上，重点在实验性结果将被安置。实验性结果将从二个系统获得。 第一，一个简单的一个自由度起重机， 作为一个实验性平台被设计。 第二是(HMF)丹麦起重机制造商捐给一所大学的真正的起重机。因为当前没有买到的（SMISMO）阀门将使用两边分开的阀门来代替。控制阀门的控制算法，在数字式Signa 将被编程Processor (DSP) /Pentium双处理器系统。 DSP将运行控制码，Pentium将做诊断并且提供一个图形用户界面。附录B1 To control a hydraulic cylinder, the strategy has to be able to handle four different situations depending on the directions of the load and the velocity of the cylinder. The control strategies that have appeared in the literature are usually quite complex and depend on measurements of the cylinder position and velocity. They are also based on rather complex control algorithms. It is the goal of this thesis to start with a control strategy which is based on simple PI controllers and makes no demands for position and velocity of the cylinder. The performance of this system will be lower than a complex control strategy, but it may be easier to implement commercially because it has no need for special sensors and is easier to understand for the average engineer.Another feature which needs to be acknowledged when designing a control strategy, is the type of valve used. Mobile hydraulic valves demand low leakage and since most mobile valves are spool valves, they usually have large overlaps. In addition, to make the cost of the valve acceptable to industry, the actuation stage on the spool is usually quite slow. This com-bination of large overlap and slow actuation makes it hard to implement many of the strate-gies that have been presented. Pressure control especially becomes difficult when there is an overlap and a slow actuator.One example of a new strategy which is simple and robust is described as follows. Flow con-trol is implemented on the inlet side and pressure control is implemented on the outlet side. The flow control is based on the Bernoulli equation. Pressure control is done by a PI control-ler which maintains a low constant pressure to increase the efficiency and prevent cavitation. To work around large overlaps and slow actuation stage, the pressure controller only does meter out control. This means that if the controller wishes to raise the pressure, it cant add flow to the cylinder, it can only decrease the opening of the meter out port. The benefit of this is that the only time that the spool has to cross the zero position is when the operator wishes to change the direction of motion of the cylinder. For the case where the load force and the velocity are in the same direction, this strategy has to be modified. In this case, the pressure reference of the pressure controller at the outlet is increased to a value which opposes the load force. The pressure reference is increased when it is noticed that the pressure of the inlet side is dropping. The pressure reference is also controlled by a PI controller. Stability was not achieved because the crane is equipped with a load holding valve. However, the load holding valve will be replaced with a pilot operated check valve, which should make it possible to stabilize the system. In current systems, the load holding valve serves two functions, load holding and runaway load protection. Due to the use of a SMISMO valve setup, the runaway load protection is built into the control strategy, therefore the only function which is necessary for the load holding valve to perform is load holding. A pilot operated check valve will be able to do this, without adding complex dynamics which upset the stability of the system.This is the general class for the pumping of fluids, and includes the pumping of slurries, fluent material and the like if handled in a manner not inconsistent with the handling of fluids. With the exception of gettering pumps as discussed in Lines With Other Classes and Within This Class, below, a pump is defined as means to move a fluid by taking it from one place or location and moving it to another place or location different from whence it came, the pump, therefore having an inlet and an outlet for the pumped fluid which are separate and distinct. The pumping of the fluid is generally accomplished by action thereon of a mechanical member (e.g., piston) or by contact or entrainment with another fluid (e.g. jet pumps). Also, the pumping may be accomplished by the direct action on the pumped fluid of an electric or magnetic force (e.g., electromagnetic pumps). However, for the line with respect to ion pumps, see Lines With Ohter Classes and Within This Class and Subclass References to the Current Class, below.VACUUM FORMATION BY GETTERINGThis class is the residual home for the formation of a vacuum in an enclosed space by a gettering action; a getter being a material which when placed in an enclosed space reduces the gas or vapor content of the space either by a chemical or physical action. Also, included are those devices and processes in which the fluid is ionized to permit or enhance the gettering action. These devices are often termed getter-ion pumps. See the notes and search notes in subclasses 48 and 49 for a statement of the lines.LINE WITH CLASS 313 AND CLASS 315For the line with Classes 313, Electric Lamp and Discharge Devices and 315, Electric Lamp and Discharge Devices: Systems, with respect to ion pumps, see Subclass References to the Current Class, below.RELATIONSHIP TO CLASS 91, MOTORS: EXPANSIBLE CHAMBER TYPERefer to Lines With Other Classes and Within This Class in the class definition of Class 91 for a statement of the line between Classes 91 and 417.RELATIONSHIP TO CLASS 92, EXPANSIBLE CHAMBER DEVICESClass 92 is directed to expansible chamber devices, per se, and with respect to nonrotary expansible chamber pumps is related to Class 417 as a subcombination thereof. Class 92 is limited to expansible chamber devices in which the working member has an oscillating or reciprocating motion to expand and contract the chamber. Thus, Class 92 cannot take the subcombination of any rotary expansible chamber pump. See the note below regarding the relationship of this class (417) and Class 418, Rotary Expansible Chamber Devices, for the disposition of this art.Set forth below are the lines between Class 92 and Class 417 as they relate to nonrotary expansible chamber pumps:A. With Drive Means1. Motor DrivenClass 92 excludes motor driven expansible chamber devices when the motor is significantly claimed. See (2) Note in Class 417 subclass 321 for a statement of what constitutes a significantly claimed motor.2. Operated By Art DeviceClass 92 excludes an expansible chamber pump mounted upon or adjacent to an art device to be operated thereby. See Class 417 subclasses 229+ for this subject matter and for a definition of an art device.3. Other Drive MechanismOther specific means to drive an expansible chamber pump such as gearing, linkage, etc., including disconnectable drives are not excluded from Class 92.B. Valving1. Pump FluidClass 92 excludes any expansible chamber pump which includes control of the pump fluid by a valving action. Thus, any claimed valving of pump fluid of an expansible chamber pump is sufficient to preclude classification in Class 92 even though the valving claimed may not be all of the valving necessary to cause the pump to operate in the intended manner.2. Nonpump FluidClass 92 does not exclude valving of nonpump fluid as, for example, valving for lubricant, coolant, sealant, etc.C. With Diverse PumpAn expansible chamber pump in combination with another pump of a different type (i.e., which, per se, would not be classified in Class 92) is excluded from Class 92 unless the pump of a different type is a mere auxiliary of the expansible chamber pump (i.e., lubricant or coolant pump, etc.).Relationship to Class 137, Fluid Handling. The line between Classes 137 and 417 isgenerally that of combination and subcombination. Class 137 generally provides for fluid handling systems and Class 417 generally provides for motor driven pumps and pumps, per se. There are certain areas of subject matter which are considered to be peculiar to pumps and their operation and are considered as exceptions to the general rule stated above. These exceptions and other detailed lines will be set out below.D. Pump-Tank RelationshipThe combination of a pump and a tank generally will be classified in Class 137. However, a single nominally recited tank, reservoir, chamber, pump or other similar fluid holding means will be considered as merely a flow line or conduit and will be classified in Class 417. See (9) Note in the Class Definition of Class 222, Dispensing, regarding other pump-tank relationships.E. Pump-Accumulator RelationshipAn accumulator or surge dampening device is usually a device having a single fluid opening and is connected to a pump inlet or outlet for the purpose of maintaining a smooth flow to or from the pump. Such devices when disclosed for the purpose of surge dampening or insuring smooth flow and claimed in combination with a pump are classified in Class 417.F. Pump-Liquid Accumulation Control Relationship1. A pump claimed in combination with a liquid accumulation controlled valve is classified in Class 137 with the following exceptions which are classifiable in Class 417:a. When the liquid accumulation responsive valve controls a liquid flow to the pump or a gas relief from the pump is for the specifically disclosed purpose of priming the pump, see Class 417, subclasses 200 and 435.b. When the liquid accumulation responsive valve functions as a pump valve in a fluid displacement-type pump, see Class 417, subclass 65 in general and subclasses 126+ and 138 in particular.c. When the liquid accumulation responsive valve is the distributor of an expansible chamber-type pump, see Class 417, subclass 297.5.2. A Jet pump claimed in combination with liquid level responsive regulating means therefor is classified in Class 417, subclass 182.5.3. A pump claimed in combination with liquid accumulation-controlled drive transmission therefor is classified in Class 417, subclass 211.5.4. A pump claimed in combination with a liquid accumulation controlled-drive motor therefor is classified in Class 417, subclasses 36.G. Pump-Plural Serial Valve RelationshipA pump claimed in combination with plural serial valves in either or both an inlet or an outlet flow path and without any branched flow paths is classifiable in Class 417. The rule for serial valves applies even though one or more of the valves is manually operated or condition responsive, see Class 417 for serial pump distributors, for a manually operated valve in serial relationship with a pump distributor, and for a condition responsive valve in combination with a pump. (See Subclass References to the Current Class, below.)H. Pump-Main Flow Path and Branched Flow Path RelationshipGenerally a branched flow system having a main flow path and a branched flow path, whether including a pump or not, is classifiable in Class 137. However, there are a number of exceptions which usually depend upon the disclosure in the particular patent as set forth below.1. A pump having plural branched flow paths, whether valved or not, communicating with a single source or receiver is classifiable in Class 417. Where there is no specific disclosure of the source or receiver for the flow paths, the disclosure will be considered as if there were a single source or receiver and will be classified in Class 417.2. A pump having a main flow path and a branched flow path, each communicating with separate sources or receivers is classifiable in Class 417 if:a. the source or receiver for the main flow path is unclaimed or nominally claimed andb. the branched flow path is specifically disclosed as a relief inlet or outlet for the pump, a priming inlet to the pump, a bypass around the pump, or a vent, waste or drain outlet from the pump, and either(1) the main flow path is uncontrolled or (2) the main flow path is controlled and the branched flow line is (a) uncontrolled, (b) manually controlled or (c) controlled by a condition responsive valve responding to a condition in the main flow path which is sensed between the pump and the main flow path controller.I. Condition Responsive Control of Pump Drive MotorA motor driven pump having a condition responsive control for controlling the operation of the motor is classifiable in Class 417. The combination of a pump and a disconnectable drive, clutch or variable transmission having a condition responsive control is classifiable in Class 417. (See Subclass References to the Current Class, below.)J. Direct Response Valve-Pump Cylinder RelationshipThe combination of one or more direct response valves of the type classifiable in Class 137, subclasses 511+ and a nominally recited cylinder is classifiable in Class 137. The specific recitation of a cylinder head is not considered to be a specific recitation of the cylinder.RELATIONSHIP TO CLASS 415, ROTARY KINETIC FLUID MOTORS OR PUMPSClass 415 takes rotary, nonexpansible chamber-type pumps. However, Class 417 provides for rotary, nonexpansible chamber-type pumps in certain combinations as enumerated below. Unless specifically excluded below, a patent to a rotary nonexpansible chamber-type pump, as defined in the class definition of Class 415, will be classified as an original in Class 415 as opposed to Class 417.1. With Drive Meansa. Motor DrivenClass 415 excludes motor driven rotary nonexpansible chamber-type pumps when the motor-pump combination is significantly claimed. For a detailed explanation of what constitutes a significantly claimed motor-pump combination see Subclass References to the Current Class in this class and Lines With Other Classes and Within This Class, General Relationship With Other Classes, paragraph A in the Class 415 definition.b. Operated By Art DeviceA rotary, nonexpansible chamber- type pump operated by an art device is excluded from Class 415. See Class 417 for this subject matter and the definition of an art device. (See Subclass References to the Current Class, below.)c. Other Drive MechanismOther specific means to drive a rotary, nonexpansible chamber pump such as gearing, linkage, etc., including disconnectable drives (e.g., clutch) are not excluded from Class 415.2. With Diverse PumpThe combination of a rotary, nonexpansible chamber-type pump with another pump of a different type (e.g., recipro- cating, rotary expansible chamber, etc.), is excluded from Class 415 and is classified in Class 417 unless the different type pump is a mere auxiliary of the rotary, nonexpansible chamber-type pump (e.g., lubricating or coolant pump). In the latter case, classification in Class 415 is proper.Relationship to Class 418, Rotary Expansible Chamber DevicesClass 418 takes rotary expansible chamber pumps even though the disclosure and claims may be restricted to pump use. In some ways Class 418 may be considered to be less comprehensive than Class 417 and rotary expansible chamber-type pumps in certain combinations enumerated below will be classified in Class 417 rather than Class 418. Unless specifically excluded below a patent to a rotary expansible chamber type as defined in the Class Definition of Class 418 will be classified as an original in Class 418 as opposed to Class 417:3. With Drive Meansa. With MotorClass 418 excludes motor driven rotary expansible chamber devices when the motor is significantly claimed even if the motor is of the rotary expansible chamber type. For a detailed explanation of what constitutes a significantly claimed motor; see Subclass References to the Current Class, below.b. Operated By Art DeviceA rotary expansible chamber pump mounted upon or adjacent an art device to be operated thereby is excluded from Class 418. See this class (417) for this subject matter and the definition of an art device. (See Subclass References to the Current, Class, below.)c. Other Drive MechanismOther specific means to drive the pump such as gearing, linkage, etc., including disconnectible drives (e.g., clutch) are not excluded from Class 418 even if the drive is not reversible.4. Valvinga. Cyclic or Position ResponsiveClass 418 will take rotary expansible chamber pumps combined with valves for the pumped fluid which have a repetitive pattern or cycle of operation which is related to the rotation of the pump. These may be termed cyclic or position responsive valving and include the opening and closing of inlet or exhaust ports by the movement of the rotor past same. The adjustment of this type valving so as to provide, for example, early cutoff of supply is also included in Class 418. The inclusion, however, of means to cutoff operation of the pump after a predetermined number of revolutions is excluded from Class 418, this being considered to be a dispensing feature for Class 222, Dispensing.b. In-LineAn in-line valve is defined as one situated in the normal line of pumped fluid flow which acts in some way to control the flow in that line, but not by diverting the fluid to a second or subsidiary flow line (e.g., bypass). Class 418 will take all in-line valves combined with a rotary expansible chamber pump which are controlled by some means other than a condition of the pumped fluid (e.g., manual throttle) and will also take those which are actuated directly by the application of the pumped fluid thereto (i.e., direct response valves). Those devices including in-line valves which are controlled by a pumped fluid condition (e.g., pressure, flow) and in which said valves are not of the direct response type are excluded from Class 418 and will be classified in Class 417 if otherwise appropriate.c. Branched Flow or By-passi. Separate Valve MeansThose rotary expansible chamber devices which include a separate valve means (as opposed to a movable chamber part as discussed in paragraph (2) immediately below) to divert or bypass all or a portion of the pumped fluid from its normal or first course of flow to a second or waste path are excluded from Class 418 regardless of whether the valve is manually or otherwise controlled unless the diverted fluid is used merely for a pump perfecting function such as lubricating, cooling, vane bias, etc.ii. Movable Chamber PartMany rotary expansible chamber pumps have expansible chamber parts which are in running contact with other chamber parts and which move from a normal or contacting position to a noncontacting position and in so moving allow passage or bypass of pumped fluid thereby. Exemplary of such parts are vanes, abutments, end plates, etc., and such parts are usually biased into contacting position by means such as a spring, pressure fluid conducted from the expansible chamber or the like. Such devices are not excluded from Class 418 even though the yielding of the part may be considered to be performing a bypassing function. However, if pumped fluid is conducted to the part for such a biasing function (e.g., behind end plate) and there is a controlled application of fluid to or release of the fluid from the bias area for the disclosed purpose of bypassing said fluid or conducting it to another point of use such devices are excluded from Class 418 and are classified in Class 417 if otherwise appropriate. Also Class 418 excludes a pump having a movable chamber part whose movement is controlled in response to the pressure or flow of the pumped fluid of a second rotary expansible chamber device.d. Reversible or Unidirectional FlowSome rotary expansible pumps are provided with adjustable or self-acting means by which for a given direction of rotation of the pump the flow may be reversed in the line in which the fluid is being pumped, or upon reversal of the direction of rotation of the pump the flow will continue in the same direction in the pumped fluid flow line. This, per se, will not serve to preclude classification in Class 418.5. With Diverse PumpThe combination of a rotary expansible chamber pump with another pump of a different type (centrifugal, reciprocation, etc.), is excluded from Class 418 and is classified in Class 417 unless the different type pump is a mere auxiliary of the rotary expansible chamber pump as, for example, a lubricating or cooling fluid pump, etc. In the latter case classification in Class 418 is proper.1 INTRODUCTIONThe goal of the thesis described in this paper is to improve the control of mobile hydraulic cranes. A mobile hydraulic crane can be thought of as a large flexible mechanical structure which is moved by some sort of control system. The control system takes its input from ahuman operator and translates this command into the motion of actuators which move the mechanical structure.The definition of this control system is purposely left vague in order not to impose any constraints on its design. The control system consists of actuators which move the mechanical structure, a means of controlling the actuators, a means of supplying power to the actuators, and a way of accepting inputs from the operator. It is this control system which is the target of this thesis. The goal is to analyze the requirements made on the control system and present guidelines for the design of new control systems.The thesis will be split into five parts:1） Analysis of the requirements of the control system, from the perspective of the operator, the mechanical system, efficiency, stability, and safety requirements.2） Analysis of current control systems and what their problems are.3） Analysis of the different options for the control system: different types of actuators,different types of control strategies, and different ways of organizing components.4.）Presentation of a new type of control system, which is commercially implementable. Asystem that will meet the needs of industry in the near future.5）Analysis of more optimized systems, with higher performance, better efficiency, moreflexible control, etc. This will be less commercially applicable but will be a startingpoint for more research.22.1 Before starting detailed work on developing new control systems, it is important to analyze what the exact demands are on the control system. The control system is influenced by many factors. For example: the mechanical structure it is controlling, the human operator, efficiency, stability, and industry regulations.Industry regulations are the first requirements that have to be addressed. Things like hose rupture protection and runaway load protection make a lot of demands on the control system. After regulations, stability is the next most important requirement; without stability the control system cant be used. Once stability has been assured, the performance requirements of the control system have to be set. They are determined by the mechanical structure of the crane and the human operator. The mechanical structure of a mobile hydraulic crane is a very large flexible structure which has very low natural frequencies. To prevent oscillations it is necessary to keep the speed of the control system below this natural frequency or to develop a control system which can increase this frequency. The human operator also imposes limits on the control system. If the control system is too slow or too fast then it is impossible for a human operator to give it proper inputs. And finally, once the regulations have been met, stability is assured, and the performance is at the right level, the power efficiency of the controlsystem has to be optimized.2.2 Analysis of Current Control SystemsBefore designing a new control system it is good to analyze the current control systems to find out what their problems are. Current control systems are mainly hydraulic and can suffer from three main problems:1. Instability2. High cost3. InefficiencyInstability:Instability is a serious problem as it can cause injury to human operators or damage to equipment. When a system becomes unstable it usually starts to oscillate violently. To avoid instability in current systems, the designers either sacrifice certain functions which are desirable,or add complexity and cost. The parameters of a hydraulic system, such as temperature or load force, also affect stability. A system that is stable with one set of parameters might be unstable with another set. To ensure stability over the entire operating range of the system, performance must sometimes be sacrificed at one end of the parameter range.High cost:Current systems are purely hydraulic-mechanical, so if the user wants a certain function, the ser buys a certain hydraulic-mechanical component. Because most users have different equirements, there are many different variations of the same basic component. This means hat many specialized components must be manufactured rather than one standard product.This drives up the cost of components.Inefficiency:One form of inefficiency in current systems is due to the link between the flows of the two ports of the cylinder. This is because most valves use a single spool to control the flow in both port causef this link, it is impossible to set the pressure levels in the two sides of the cylinder independently. Therefore, the outlet side will develop a back pressure which acts in opposition to the direction of travel, which increases the pressure required on the inlet side to maintain motion. Since the force generated by the actuator is proportional to the pressure difference between the two sides, the actual pressures in the cylinder dont affect the action of the cylinder. For example, the action of the cylinder for 0psi/600 psi would be the same as 1000psi/1600psi. However, in the second case, the power supply would have to supply much more power. This extra power is wasted.2.3 Different Options for Control SystemsCurrent control systems use hydraulic actuators with directional/proportional valves to control the movement. However there are many different options for controlling a cylinder. Options range from new high performance electro-hydraulic valves, to separate meter in / separatest. meter out (SMISMO) valves, to hydraulic bus systems, to intelligent actuators with built in power supplies, to pump based control strategies. These systems all have advantages and disad
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