15 tips for introductory mechanical design, novices remember to collect
some words although they are clichés, but as the saying goes: learn the new by reviewing the past. . .
Learning machinery, structural design, how many mistakes, how many detours, and constantly summing up experience from them, can we design satisfactory products according to customer requirements and even become a master in this industry. Yes, experience is a valuable asset for our personal design path, whether it is our own experience or the experience of others, it cannot be ignored.
1 worship imitation as a teacher, learn from imitation, and continuously improve
80-90% of the usual designs are imitated and synthesized from existing technologies. Make full use of other people’s experience and past experience to serve yourself and make continuous progress.
2 be obsessed with design
Designers must have an aesthetic view, a view of stability, and be able to distinguish between beautiful and unbeautiful products, stability and instability. Secondly, the designer should put himself in the shoes of the user and experience from the user's standpoint. Confidence comes from the fascination with design, like a lover, fascinated with design, using all the energy and talent, this is the foundation of confidence, but also the secret of conquering users and being liked by users.
3 Shape and structure are generated by force
Machine products are all working under load, and the design is based on the strength of the weakest part, the load is checked, and the force analysis is the backing. (In the design of electronic equipment products: plastic parts are mainly used for rigidity checking, metal parts are mainly used for strength checking)
4 Drawings are more important than theory, and facts are more important than drawings
The designer must use the designed drawings to express his ideas. The drawings deal with theoretical and engineering issues reasonably. This means that drawings are more important than theory; it is actually the source of designers. When they hear that they cannot be manufactured according to the drawings or users’ opinions, It should be taken seriously and not sloppy.
5 Deeper understanding after use
If the test is qualified in the factory, there will be problems in actual use, because the user's site conditions are different from those of the manufacturer; the workers may not have mastered the operation essentials, and maintenance is inconvenient. Therefore, the design should not only be satisfied with the original goals and requirements. Collect the situation at the use site, find various problems, improve the design, ensure product quality, keep production normal, reduce costs, and reduce consumption.
6Don't blindly pursue high precision
Due to large errors in assembly, the failure of normal assembly is often the source of wrangling and complaining between the processing workshop and the design department, so the designer narrowed the tolerance range. The cost of the product rises in the geometric progression of accuracy, and the designer's slight negligence in his writing may cause the cost to rise linearly. Several parts that meet the accuracy may not be able to be installed, which is a problem of the dimensional chain. Setting aside an adjustment position in a certain link of the dimensional chain and temporarily processing after assembly can achieve the purpose of assembly, and the accuracy may not be set very strict. The design must ensure that the product is reliable in use, easy to operate, easy to manufacture, and easy to maintain. To do this, you need to exercise hard and study hard, which is by no means a day's work.
7Multi-purpose standard parts, general parts
The machinery manufacturing industry has become more and more specialized. If you want to rely on your own factories to manufacture everything, this is neither economical nor invalid, and it is an outdated idea. In the design of a new product, universal parts and standard parts should be used as much as possible. This can shorten the production cycle, but also facilitate interchange and reduce costs. With the continuous development of industry, specialization will inevitably develop vigorously. Designers should understand the development of specialization and be familiar with the common parts, standard parts and other components that the market can provide in order to select them correctly.
8 Avoid flashy and pretentiousness
Design flashy and pretentiousness are harmful to design work. The former is easy to happen to young designers, and the latter is easy to come from old designers. Ignore the constraints of reality, such as delivery time, cost, material supply, equipment capabilities, processing and assembly, and overhaul capabilities, etc., blindly designing according to their own ideas, the hope of success is very small, and fledgling designers are not afraid of being born. The vigor of the tiger is anxious to fly freely with wings. This is good, it is a spirit, and should be maintained and carried forward, but we should face reality, avoid flashy, and avoid wasting energy and time. The experienced person cannot fall under the feet of past experience, so that he has no courage to take risks and stop.
Technology is constantly advancing, and product competition is continuing, which requires designers to constantly explore and design good products. Things are changing. In the past, it was an obstacle that prevented progress. It may have become a condition that can be used. The key to preventing complacency lies in learning. Designers must keep this in mind to live and learn. The past experience is valuable, and the value is obtained with one's own enterprising spirit. Enterprising spirit is the sword of bravery and courage in career. The sword should always shine.
9 one has three
As the saying goes: There are three if there is one. If the product is faulty and not handled carefully, there will always be one or three cases. When problems arise, they do not go to thorough investigations and in-depth analysis, but subjective assumptions and wrong handling. This will lead to repeated problems.
Design is the basis of production. Products must undergo trial production to test the design and inspect all production preparations to make production proceed smoothly. If production changes frequently, the production cycle, product quality, and manufacturing costs will be greatly affected, and production changes Because of the greater influence of design, design changes must be kept to a minimum, and changes must be made decisively, quickly, and carefully. They should have foresight into problems and eliminate accidents before they happen. To sum up, the problem must not be taken lightly, and the root of the problem must be found.
10 The problem is easy to be neglected
The experience of life and work has enlightened us that failures and faults often appear in places that people did not expect. Generally, there will be no problems after careful consideration, such as the calculation of mechanical strength, and always think carefully about the safety of a certain part. I was afraid that it would go wrong, on the contrary, there would be no problem. Instead, the "alarm" was raised in a place that I didn't expect. After the analysis, I realized that the "alarm" was justified, and I really ignored the force analysis there. The reason for this is negligence. When a weak link is found in the design, we must grasp it and solve it. This is an ability that needs to be cultivated. Advanced designers can generally do this. Every designer should maintain meticulous, strict requirements, and perseverance from the beginning of design. Over time, he will be able to develop agility and neatness.
11 Inheritance is a shortcut to design
There are two types of design, one is a new design without experience to follow, and the other is a design using data or experience. Generally speaking, design is inherited design.
A drawing has to go through many tests. The more tested the drawing, the more valuable it is. The record of proprietary changes on the drawing represents the footprints of a part or even a product in practice, which can reflect such things as structure, material, size, Changes and problems in tolerances, processing, measurement and assembly, testing, etc., are extremely precious materials in design. Those who are interested will cherish this experience and use it effectively as experience and materials for new product design.
12 late drawings equal waste paper
The designer should pay special attention to the delivery date of the product. Why is delivery time important?
(1) Manufacturers should make their own production schedule as far as possible to meet the requirements of users, and product design is an important part of the entire production process.
(2) The product life cycle is shortening day by day. In order to stay ahead, the speed of technology update should be accelerated.
(3) Whether there is a rhythm in production has an impact on product quality and cost. When the drawings are late, surprises in production and hasty delivery, especially inadequate inspections and experiments of the products before leaving the factory, often cause unexpected problems with the products, causing dissatisfaction and distrust of users.
(4) The late drawing is the main reason for the contradiction between the physical object and the drawing. In order to catch up with the production schedule, the products cannot be processed without formal drawings, which will inevitably be inconsistent with the drawings.
In addition, design is different from other work. It is a conceivable and deliberative work. It may not be carried out strictly according to the advance schedule, but it must be carried out according to the schedule. This requires more preparation, accumulation, and support. Thousands of days, the use of troops for a while, should also take some measures to save design time, such as using white drawings or size tables. Often new designs are shelved, which is the result of missed opportunities.
There is PERT (programeval_ruationandReviewTechnique that is the estimation and verification technology of design workload) on the effective management method of design drawing or delivery date, and designers should master it as soon as possible.
13 Keep things you don’t understand
When designing a product, it is often necessary to refer to the products or materials produced by other factories, and there are often some questions, such as: "Why is it designed like this", or "It is better to change it", etc., but after the change, it is not the processing technology. Not good, it is easy to malfunction, and it is too late at this point.
These problems are caused by lack of experience and insufficient information, and experience and information do not come right away, and rely on accumulation. Wherever you feel suspicious about something imitated, but you are not sure what the problem is, in order to prevent the painting of a tiger from becoming an anti-dog, it is best to leave it alone and study it later. It is impossible for us to anticipate all the problems, so we must respect the experience accumulated by our predecessors.
14 make effective use of the original design
If you want to modify another person's design, you must first understand the ideas and principles of the design. Don't make drastic changes lightly, and don't make changes to the east or west rashly. This is often self-defeating. The design should be better. If the benefit of 20~35% is not achieved, don't change it.
Only 5 to 6% of the benefits, I am afraid it can only compensate for the funds spent on changing the design. When changing the design, the situation of finished products and semi-finished products should also be taken into consideration and used as much as possible. There must be reasons for changing the design, but the impact on production after the change and the possible new contradictions should still be considered. Sometimes it is found that the original design principle is wrong and must be completely changed. At this time, the design leader has a heavy responsibility, whether to push it over or tolerate it, and to take the overall situation and make decisive decisions.
15 The introduction to mechanical design is done, definitely not by asking
Thought is the forerunner of action. If you know how to enter the door of mechanical design, you can indeed speed up the entry speed. If you have the opportunity to go to the workshop, you must learn well. In the workshop, it is a basic accumulation. The high-rise building rises on the ground and depends on the foundation. The workshop is a process of laying the foundation, a process of taking root, and a process of accumulation. Only by laying the foundation, deepening the roots, and accumulating enough, can you complete more and more powerful designs. Starting from the workshop processing technology, starting with tooling and fixtures, you must be able to use 2D and 3D drawing software. Drawing software is not omnipotent, and no software is absolutely impossible.