Mechanical design is a major with a wide range of employment directions, but it is not so easy to learn mechanical design well.
Next, summarize the following 12 knowledge points related to mechanical design, and judge whether you have entered mechanical design after graduation.
1. What are the reasons and measures for the anti-loosening of threaded connections?
Under the action of vibration, shock and variable load, the preload may disappear at a certain moment, and the connection may be loosened;
Loosening may occur in high-temperature threaded connections due to differences in temperature deformation, etc., so it is necessary to consider anti-loosening in the design.
Anti-loosening measures - use additional friction to prevent loosening, such as using groove nuts and cotter pins, stop gaskets, etc.;
Other methods of anti-loosening, such as punch point method anti-loosening, adhesive method anti-loosening.
2. What are the main parameters of gear design? What are Displacement Gears?
Tooth top height, modulus, pressure angle, number of teeth).
3. What are the main failure modes of rolling bearings?
pitting, gluing, abrasion).
Fourth, measures to improve the strength of bolt connections.
5. What is a two-force member?
A rigid body that is only balanced under the action of two forces is called a two-force body or two-force member.
6. How to calculate the degree of freedom of the mechanism? The judging body has the conditions to determine the movement.
Seventh, list three kinds of 90-degree flip station mechanism.
8. List the mechanisms for turning rotary motion into linear motion.
9. What is institutional self-locking? What are the conditions for the occurrence of mechanism self-locking, and list a few common self-locking mechanisms.
10. Why does the belt drive slip? How to avoid it?
Cf. *** ten.
1. What are the key points of shaft structure design?
1) The shaft should be easy to process, and the parts on the shaft should be easy to assemble and disassemble.
2) The features on the shaft should have accurate machining positions.
3) Each part should be firmly and reliably fixed relatively.
4) Improve the stress condition and reduce the stress concentration.
Ten. 2. Why do worm drives need to calculate thermal balance?
The worm transmission efficiency is low, the heat is large, if the heat is not dissipated in time, it will cause the oil temperature in the box to rise, lubrication failure, resulting in aggravated gear wear, and even gluing, so the thermal balance calculation should be carried out on the closed worm transmission for continuous work).