Rebirth of Jinse Nianhua

"Gear transmission refers to a device that directly transmits motion and power with the teeth of the main and driven wheels. Among all mechanical transmissions, gear transmission is the most widely used and can be used to transmit motion and power between two shafts that are not far from each other. "

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"The characteristics of gear transmission are: stable gear transmission, precise transmission ratio, reliable operation, compact structure, high efficiency, long life, and wide range of power, speed and size used."

"For example, the transmitted power can range from very small to hundreds of thousands of kilowatts; the speed can reach up to 300m/s; the diameter of the gear can range from a few millimeters to more than 20 meters."

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"But making the gears requires specialized equipment, and the meshing transmission creates noise."

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In the crowded mechanical design class, the teacher memorized the content of the chapter explaining gear transmission in "Mechanical Design" while writing and drawing on the blackboard. student with notes.

I am also one of the three hundred people. The difference is that my mind is not in the classroom at all, my mind is blank, I don’t know where to draw ink with the hand holding the fountain pen, and the open textbook is clean. I couldn't find any notes of a word, and the teacher's passionate speech sounded like an echo in the valley to me, far enough away but not clear enough.

It has been a whole week, and the situation of Yushen Creative has not shown any signs of improvement. Instead, it has lost five or six customers who have been working happily together. Although the sum of these customers is not enough to bring Yushen Creative back to life, But in this tense moment when people need help most, it is tantamount to adding insult to injury.

Song Yu originally wanted to listen to my suggestion and go to Song Mi to find a solution, but it happened that Song Mi was filming abroad and couldn't return to the country in a short time.

Due to the huge psychological pressure and various malicious speculations from the outside world, Song Yu lost more than a circle of weight in just a few days, and the tiredness between his brows and eyes could not escape my eyes no matter how much he pretended.

I feel sorry for him, especially for him.

But what can I do for him?

Is it really necessary to take that step?

In case of flooding...

"Ruan Jitong!"

Accompanied by this sullen middle-aged male voice, my forehead was gorgeously hit by a small white thing, and the faint pain pulled me back from my chaotic thoughts in an instant.

I rubbed my itchy forehead, followed the arc where the little thing bounced back from my forehead just now, and soon found the murder weapon—half a piece of chalk.

"Ruan Jitong, stand up and answer a few questions for me." Lao Cao folded his hands in front of his chest, standing crookedly with his right foot one and a half way beyond his left foot, and a few strands of gray hair in the shape of chrysanthemum petals funnyly pasted on his plump body. On his forehead, there was an expression of condescension and disdain that was irrelevant, "Close the textbook, no peeking!"

Apart from Lao Cao's voice, there were only three hundred intertwined and messy breathing sounds in the huge lecture hall. No one dared to laugh or whisper to each other at such a time.

Lao Cao is the deputy dean of the School of Mechanical Engineering, and concurrently serves as the teacher of our 2011 freshmen major in mechanical design. He is arrogant, unrecognizable, and neurotic. Toughness doesn’t work for him. If you don’t listen carefully to the class, you will be smashed. After decades of careful implementation, the accuracy of Lao Cao’s throwing chalk tips has reached the level of horror that both humans and gods are angry with. In the third row, even if I sit in the last row, his chalk head can accurately chase me down.

I secretly rolled my eyes a few times, and I thought that you deserved to be the deputy dean for the rest of your life, but I also knew the truth that "one who knows current affairs is a hero", so I stood up obediently after only two seconds , By the way, I closed the textbook tightly.

Seeing me cooperate so much, Lao Cao flattened his mouth in an ugly way, stared at me, looked up and down, and snorted softly in his nose: "Tell me about a problem I just mentioned, according to the relative position of the two axes And the direction of gear teeth, what types of gear transmission can be divided into?"

As soon as Lao Cao's voice fell, the sound of flipping through the books immediately sounded in his ears, which was very uniform.

I secretly laughed in my heart, kept a humble look on my face, and replied loudly: "Spur gear transmission, helical cylindrical gear transmission, herringbone gear transmission, bevel gear transmission, cross-axis helical gear transmission."

The gloomy smile on Lao Cao's face froze for an instant, he stopped doing his hands, and stopped posing with his feet one after the other. He asked again: "According to the working conditions of the gears, how many types can they be divided into?"

I thought about it pretending to be thinking carefully, and then answered fluently: "Open gear transmission, the gears are exposed outside, so good lubrication cannot be guaranteed. Semi-open gear transmission, the gears are immersed in the oil pool, and there is a protection Cover, but not closed. Closed gear transmission, gears, shafts and bearings are all installed in a closed box, with good lubrication conditions, dust and sand are not easy to enter, accurate installation, gear transmission has good working conditions, and is the most widely used gear transmission."

Now Lao Cao's complexion was even more ugly, and the corners of his wrinkled eyes twitched cautiously.

Under normal circumstances, people who are called up by Lao Cao to answer questions will end badly. What is the reason?Lao Cao's character is really bad, and he really wants to save face. If he asks you to get up and answer questions, it may only be because you didn't listen carefully in class and got distracted, because he wants to take this opportunity to criticize | To elevate himself, so the question he asked is absolutely impossible to ask in class as he said, and the answer he hopes to get is not a standard answer. Simply put, he just thinks that you can’t answer it or answer it wrong So severely belittle you meal.

I think my "outstanding performance" today should have created a historic milestone in Lao Cao's decades of teaching career. From his unpredictable and rich expressions, we know that he is very stimulated.

Sometimes I also develop some bad tastes that are not elegant, such as now.

Pretending to cough twice, I added another sentence like chasing after the victory: "If the gear transmission is classified according to the shape of the gear, it can be divided into cylindrical gear transmission, bevel gear transmission, non-circular gear transmission, rack transmission and worm transmission."

People all over the world testified to me that Lao Cao almost fell off the podium as soon as these words came out. Fortunately, he quickly supported the corner of the podium and stabilized his body quickly. dark day.

"Am I right, teacher?" I innocently threw a modest smile at Lao Cao, and put my hands behind my back to show my respect for him.

"Uh...that's a good answer." Lao Cao smiled awkwardly, then waved me to sit down, "However, even if you understand all these knowledge, you have to listen carefully to the teacher's lecture, you know?"

I nodded like a pounding garlic, trying my best to look like a good student.

Lao Cao is hateful, but he is not so bad that he turns black and white. Apart from the problem of character, his academic achievements cannot be ignored. I have to admit this with conscience.

If I hadn’t been reborn with the memories of the previous life, and I could recite the professional knowledge that I have already mastered, I would definitely be dumbfounded when I was asked these questions, so it is really wrong for Lao Cao to encounter Waterloo this time.

2013-10-22

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