.机械设计理论机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科形状和详细结构的基本主要研究产品的尺寸、学。
它涉及工程技术的各个领域，构思，还要研究产品在制造、销售和使用等方面的问题。
机械设进行各种机械设计工作的人员通常被称为设计人员或者机械设计工程师。
还必须在机械制设计工程师不仅在工作上要有创造性，计是一项创造性的工作。
材料力学和机械制造工艺学等方面具有深厚的基础知识。
工程材料、图、运动学、发现和科技机械设计的目的是生产能够满足人类需求的产品。
发明、如前所诉，知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效必须先确定人们是否需因而，应该认识到在一个特定的产品进行设计之前，益。
要这种产品。
系统分析应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、掌握工程基础知识要比熟记一些数据和公和制定产品的制造工艺学的一个良机。
仅仅使用数据和公式是不足以在一个好的设计中做出所需的全部决式更为重要。
定的。
另一方面，应该认真精确的进行所有运算。
例如，即使将一个小数点的位置放错，也会使正确的设计变成错误的。
当新的方而且愿意承担一定的风险，一个好的设计人员应该勇于提出新的想法，所花费法不适用时，就使用原来的方法。
因此，设计人员必须要有耐心，因为为要求屏弃许多陈旧的，的时间和努力并不能保证带来成功。
一个全新的设计，一位机由于许多人墨守成规，这样做并不是一件容易的事。
人们所熟知的方法。
在此过程中应该认真选择原有械设计师应该不断地探索改进现有的产品的方法，的、经过验证的设计原理，将其与未经过验证的新观念结合起来。
只有当这些缺陷和问题被解决新设计本身会有许多缺陷和未能预料的问题发生，之后，才能体现出新产品的优越性。
因此，一个性能优越的产品诞生的同时，也就没如果设计本身不要求采用全新的方法，伴随着较高的风险。
应该强调的是，有必要仅仅为了变革的目的而采用新方法。
即使产不受各种约束。
应该允许设计人员充分发挥创造性，在设计的初始阶段，只有也会在设计的早期，生了许多不切实际的想法，即绘制图纸之前被改正掉。
这样，才不致于堵塞创新的思路。
通常，要提出几套设计方案，然后加以比较。
很有可能在最后选定的方案中，采用了某些未被接受的方案中的一些想法。
...设计人员的基本职责是努心理学家经常谈论如何使人们适应他们所操作的机器。
因为实际上并不存在着一个对力使机器来适应人们。
这并不是一项容易的工作，所有人来说都是最优的操作范围和操作过程。
在开始另一个重要问题，设计工程师必须能够同其他有关人员进行交流和磋商。
这一并得到批准。
阶段，设计人员必须就初步设计同管理人员进行交流和磋商，，需要解决般是通过口头讨论，草图和文字材料进行的。
为了进行有效的交流下列问题：）所设计的这个产品是否真正为人们所需要？（1 此产品与其他公司的现有同类产品相比有无竞争能力？2（）生产这种产品是否经济？（3）产品的维修是否方便？（4）5）产品有无销路？是否可以盈利？（产品的设计、制造和销售只能在只有时间能对上述问题给出正确答案。
但是，设计工程师还应该通过零件图和装配对上述问题的初步肯定答案的基础上进行。
图，与制造部门一起对最终设计方案进行磋商。
，在制造过程中会出现某个问题。
可能会要求对某个零件尺寸或公差作一通常工程上的更改必须要经过设计人员批准，些更改，使零件的生产变得容易。
但是，在产品的装配时或者装箱外运前的试验中才以保证不会损伤产品的功能。
有时，总是存在着发现设计中的某种缺陷。
这些事例恰好说明了设计是一个动态过程。
更好的方法来完成设计工作，设计人员应该不断努力，寻找这些更好的方法。
选择过程应该是一个对材料的工程材料的选择已经显得重要。
此外，近些年来，而一些原有的材料的能够获得的数新材料不断出现，连续不断的重新评价过程。
工人的健康及安全等方面经常会对材料的回收利用、量可能会减少。
环境污染、可能会要求使用不同材料选择附加新的限制条件。
为了减轻重量或者节约能源，对产品维修保养方便性要求的提高和顾客的反馈的材料。
来自国内和国际竞争、由于材料选用不当造成的产等方面的压力，都会促使人们对材料进行重新评价。
材料与材料加工之间的相互依赖关此外，品责任诉讼，已经产生了深刻的影响。
为了能在合理的成本和确保质量的前提下获系已经被人们认识得更清楚。
因此，确定和使用材设计工程师的制造工程师都必须认真仔细地选择、得满意的结果，料。
...）a制造任何产品的第一步工作都是设计。
设计通常可以分为几个明确的阶段：（）生产设计。
在初步设计阶段，设计者着重考虑cb）功能设计；（初步设计；（然后决定这种思想是否可行；通常要设想和考虑几个方案，产品应该具有的功能。
关于材料在此阶段，如果可行，则应该对其中一个或几个方案作进一步的改进。
如果没有的话，是否有性能符合要求的材料可供选择；选择唯一要考虑的问题是：是否有较大的把握在成本和时间都允许的限度内研制出一种新材料。
在这个阶段要绘制出在功能设计和工程设计阶段，要做出一个切实可行的设计。
通常要制造出样机或者实物模型，相当完整的图纸，选择并确定各种零件的材料。
并对其进行试验，评价产品的功能、可靠性、外观和维修保养性等。
虽然这种试验可能会表明，在产品进入到生产阶段之前，应该更换某些材料，但是，绝对不认真仔细地考虑能将这一点作为不认真选择材料的借口。
应该结合产品的功能，所选用成本和可靠性。
一个很有成就的公司在制造所有的样机时，产品的外观、这样对并尽可能使用同样的制造技术。
的材料应该和其生产中使用的材料相同，公司是很有好处的。
功能完备的样机如果不能根据预期的销售量经济地制造出则这种样机或者是样机与正式生产的装置在质量和可靠性方面有很大不同，来，选择和设计工程师最好能在这一阶段完全完成材料的分析、就没有多大的价值。
在生产设计阶段材料的更因为，确定工作，而不是将其留到生产设计阶段去做。
换是由其他人进行的，这些人对产品的所有功能的了解不如设计工程师。
使它们在生产设计阶段中，与材料有关的主要问题是应该把材料完全确定下来，而且材料的数量能够与现有的设备相适应，能够利用现有设备经济地进行加工，比较容易保证供应。
经验表明，不可避免地会出现对使用中的材料做一些更改的情况。
在制造过程中，在进行生产以后改换在大多数情况下，可采用某些便宜材料作为替代品。
然而，在设计阶段做好材料选择工材料要比在开始生产前改换材料所花费的代价要高。
在生产制造开始后出现了可供使用的新材料是更可以避免多数这样的情况。
作，换材料的最常见的原因。
当然，这些新材料可能降低成本、改进产品的性能。
但是，必须对新材料进行认真的评价，以确保其所有性能都满足要求。
应当记住，大部分的产品失效和新材料的性能和可靠性很少像现有材料那样为人们所了解。
没有真正了解它们的产品责任事故案件是由于在选用新材料作为替代材料之前，长期使用性能而引起的。
...在材料过产品的责任诉讼迫使设计人员和公司在选择材料时，采用最好的程序。
）不了解或者不会使用关于材料应用方面的最程中，五个最常见的问题为：（a未能预见和考虑擦黑年品可能的合理用途（如有可能，(b)新最好的信息资料；在近年来的设计人员还应进一步预测和考虑由于产品使用方法不当造成的后果。
许多产品责任诉讼案件中，由于错误地使用产品而受到伤害的原告控告生产厂所使用的材料的数据不全或是有些数据不确定，尤其(c)家，并且赢得判决）；由(e)(d)质量控制方法不适当和未经验证；是当其长期性能数据是如此的时候；一些完全不称职的人员选择材料。
对通过对上述五个问题的分析，可以得出这些问题是没有充分理由存在的结论。
尽管采用最好的材料这些问题的研究分析可以为避免这些问题的出现指明方向。
设计人员和工业界按照适当的程序进行选择方法也不能避免发生产品责任诉讼，材料选择，可以大大减少诉讼的数量。
特点和加工方法有选择材料的人们应该对材料的性质，从以上的讨论可以看出，一个全面而基本的了解。
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