Mechanical design is often inseparable from one's own experience. Although you can learn a lot from books when accumulating experience, it is difficult to leave a deep impression in your mind without doing it yourself. For other people's experience, your own Without a certain foundation, it is really not easy to understand and absorb. hehe.

Mechanical design runs through the entire process of design, manufacturing, use, and maintenance. Negligence during design will always be reflected in these aspects. Success or failure is easy to judge. The design process is greatly influenced by manufacturing, which means that good design cannot be separated from manufacturing. The better you understand manufacturing, the more helpful it is to improve your design level. After the designed drawings are put into production, I have not seen many people who can immediately process and assemble them according to the drawings. It is very common to find a lot of problems during the drawing review and process, including the drawings produced by the so-called "senior" senior engineers and chief engineers. It is the result of repeated discussions after many meetings. The reasons are multi-faceted. The standardization of the drawing and the level of the reader are on the one hand, but the designer's lack of in-depth understanding of the manufacturing process is the main reason. How do you determine how much you know about manufacturing? The easiest way is to grab a drawing of something you designed. Can you tell me the entire manufacturing process? Casting, forging, turning, pliers, milling, planing, grinding, just like this, it is definitely not possible. Who has worked in a machinery factory for several years doesn't know? It must be broken down to fully understand each process. For example, how to part the mold during casting, how to place the gates and risers, what kind of casting defects may occur, whether the part structure will cause accidents during heat treatment, how to optimize the part structure, and cutting processing. The process is virtualized in the mind, including the total number of knives used, the rotation speed, the amount of tool feed, even where the iron chips fly, the order in which the knives are used, the entire operation of the lathe, miller, and grinder, and so on. Wait until you have a better foundation. This does not mean that those who engage in design must be able to use lathes, milling machines, and electric welding, but you must know the characteristics of these operations and fully consider them during design. As a mechanical designer, only in this way can you be better than those who use electric welding on a cranking lathe. There is a place to live and settle down. In this way, during the design process, some unreasonable structures will be avoided, and the quality of the design will naturally improve a lot, but it is not enough. A technician with ten or eight years of service can come up with a more mature detailed plan than you (although the overall (They can't do the design coordination), but how many sleepless nights have been spent to design just such a result? Isn't it a shame to be polite? The only solution is to read more books. What others summarize is usually combined with production and is the result of hard work. Study with questions, and you can digest them by thinking more. You will no longer give stupid answers like "just ensure concentricity." The key is that you have pointed out the methods to ensure concentricity, and even the mistakes of your predecessors. At this time, no one calls you Xiao Qian or Xiao Zhao anymore. Even the boss calls you Qian Gong or Zhao Gong, which is quite respectable. I touched my chin, my beard had grown, my diaper was lost, my child called me mom, and I felt a sense of accomplishment. But design is always for use, and good design must have a little bit of humanity. Design a set of process equipment, and once it is put into trial production, the efficiency and quality will be good, and the boss will have a drink to celebrate. After a few days, I found that it was abandoned because the operator was swearing. It's painful to use. And there are so many details to pay attention to. If someone else was just an operator, he wouldn't still be an operator there if he considered so many factors. If the design is not conducive to use, it will be eliminated. There are many complete sets of equipment, such as automobile engine gearboxes and the like, which are "fine" when operating normally, but one of the small keyways, a bearing position, or something is broken, and the entire It just couldn't be used. The factory only sold the whole unit, not the accessories. I really didn't have any place to add enhancements myself. I went to several factories to buy them, and there were a lot of them. The users had no choice but to stay away from them, and set up a technical transformation project - - Poor technical modification. Anyone who has been in the machinery industry for a long time will have seen and heard of such things. Use is inseparable from maintenance, and good design cannot ignore maintainability. In a large production line, key equipment is only repaired twice a year. However, each time the equipment must be dismantled into pieces, forklifts, jacks, crowbars, and other weapons are not enough. The master craftsmen also had to use their own brains and hands to create a few useful special items to serve them. As a result, the loss from the discontinuation of production exceeded the value of the equipment itself. It was a silent ending.

A set of large equipment requires almost complete disassembly of the whole machine just to replace an oil seal or something. It would be strange if the user does not accuse the design of doing something that will destroy the descendants of the descendants. It is really the sorrow of the designer

Our design must not only be based on manufacturing, but also be innovative, but we must learn to inherit. Now, the whole society is emphasizing innovation, but we cannot look down on the original things just as we emphasize innovation. There are usually two types of innovation, one is the recombination of the old elements that make up things, and the other is the addition of some new elements to the old elements. Therefore, no matter what, it is undeniable that innovative things always contain some shadow of old things. As it is said in philosophy, new things are produced by negation in affirmation, and affirmation in negation. For example, although we humans are said to be the proud sons of nature, in fact, 99% of our genes are the same as those of gorillas. If humans did not make a 1% breakthrough based on inheriting gorilla genes, the emergence of humans would be unimaginable. If someone says that I am ambitious and do not need to inherit gorilla genes, I will create a 100% pure human gene myself. , then you won’t be able to create a single human being even in another 100 million years. Therefore, we cannot abandon all the old things for the sake of innovation. The original thing is like a dish, and innovation is like a little bit of seasoning. With such a little bit of seasoning, the dish tastes more delicious. But for the sake of pure deliciousness, no one would skip the vegetables and only come with a plate of stir-fried condiments. Therefore, we emphasize innovation, but we must not forget inheritance. Only inheritance without innovation is just being conservative, and only innovation without inheritance is just a castle in the air. Many people may think that cloning is the safest and most trouble-free design method. But as someone who works in the design industry, cloning is a shameful thing. The so-called one copy, two modifications and three creations. It succinctly summarizes the growth path of designers. When you first get started, you can only copy, but while copying, you must try your best to understand the original designer's intention and thinking, understand the transmission of the entire machine, the interrelationship between each device, and the interrelationship between each part. After that, the drawings can be produced, and there will be clear dimensional matching requirements and geometric tolerance constraints on the drawings. I just drew it and randomly drew a few lines on it. I probably felt that the accuracy of the machine was relatively high, so I pushed the accuracy up as hard as 0.005 or 0.002, and signed my signature in the design column on the drawing without shame. He claims that what he does is very precise. These so-called mechanical design engineers are everywhere.

Imitating excellent works is the only way for every designer. But when doing design, you must have your own ideas, and people must have their own distinctive personality. Over time, they will form their own style. The development of style is directly related to a person's artistic quality and personal accomplishment. The things produced by verbose people are just that verbose, the things produced by stingy people are petty, and the machines produced by irresponsible people are as irresponsible as their moral character. Being able to have your own design concept and design style is different, and the things you create will have a unique soul. Connoisseurs can tell at a glance that this is a masterpiece of care.

When you accumulate experience when plagiarizing, you should learn with a negative attitude. Check the information, read more classic design cases, and design taboos, and compare them with some things you have come into contact with, and you will make a big improvement. The surgery can be performed on existing machines. For example: increasing the added value of the machine, improving more functions, and making the whole machine more reliable. In order to cater to high-end customers; or to streamline the structure, retain some commonly used functions, reduce costs, and meet the needs of customers who cannot afford to buy and use multi-functions. By doing this, you can start getting started with mechanical design. It's hard to say whether you can become a world-class inventor, haha. But with my many years of experience and knowledge, it is not difficult to combine, mutate, and graft some structures to create something new. Instead of spending a lifetime studying profound topics such as perpetual motion machines, or working on some so-called patents that somehow cannot create any value, it is better to use your limited life to do something that can leave a mark on this beautiful planet. When I get old and almost die, I will still think about it when I die. I have lived for so many years and fiddled with so many machines on the earth, which is enough to make me smile.

To be truly a mechanical design engineer requires ten or more years of hard work. You also need considerable talent, hard work and a nurturing environment.

Genius is equal to 99% diligence + 1% hard work. In fact, it does not mean that you will achieve success as long as you work hard. What this sentence says is that if a person does not have the 1% talent for a certain profession, no matter how hard he works, it will be useless. Diligence is a way to discover one's talents and is one of the necessary conditions for achievement, but not all. Absolutely not.

The principles for selecting materials for mechanical parts should consider three requirements

1. Usage requirements (primary consideration):

1) Working conditions of the parts ( Vibrations, shocks, high temperatures, low temperatures, high speeds, and high loads should all be treated with caution);;

2) Limitations on the size and quality of parts;

3) The importance of parts. (The relative importance of the reliability of the complete machine

2. Process requirements:

1) Blank manufacturing (casting, forging, plate cutting, rod cutting);

2) Mechanical processing;

3) Heat treatment;

4) Surface treatment;

3. Economic requirements:

1) Material price (comparison of blank cost and processing cost of ordinary round steel and cold-drawn profiles, precision casting, precision forging,);

2) Processing batch size and processing cost;

< p>3) Utilization rate of materials; (such as plates, bars, and profiles, use them reasonably)

4) Substitution (try to use cheap materials to replace relatively expensive rare materials, such as In some wear-resistant parts, ductile ink is used to replace copper sleeves, oil bearings are used to replace some turning sleeves, and when the speed load is not large, nylon is used to replace steel gears or copper worm gears, etc.).

In addition, the supply of local materials must also be considered.

Basic requirements for mechanical design

a) Pay attention to coordination and balance in the functional requirements of the machine! Prevent the emergence of the barrel effect

b) Requirements for machine economy Design economy, put it into production in a short time, recover the consumption during the development period, and even design and manufacture at the same time, use economy requirements Have the best performance-price ratio (products will make money in the beginning when they are made in small batches, and they will be better when modified later)

2. Basic requirements for the design of mechanical parts

a) Before booking Work normally and reliably within the working period to ensure the various functions of the machine

b) Minimize the production and manufacturing costs of parts

c) Use as many common market standards as possible pieces.

d) For products that may be serialized, try to consider the versatility of the parts when starting the design. Those that cannot be universal should be as similar in structure as possible to reduce the process arrangement of the manufacturing process. , the workload of fixture tooling design.