"Giggle~! Tiedan, do you still have to ask? Looking at Brother Qingque's expression, he must have failed~! I just said that without my brother's help, he would definitely not succeed~!"
Lan'er pointed at Li Tai and chuckled.
Lan'er's words were cruel, and they directly pierced Li Tai's heart. The little fat man's face darkened, and he almost vomited a mouthful of blood.
Li Zexuan was afraid that he would be too embarrassed, so he said to Lan'er: "Okay, okay~! Lan'er, go play~! I'll go find you when I'm done~!"
After that, he took the pen and paper from Li Tai's hand and walked to the desk beside him and sat down.
When Lan'er saw this, she also understood that Li Zexuan would be busy with business matters next, and they were all business matters that she was not interested in, so she said "Oh" and went out.
Li Tai breathed a sigh of relief, came over and asked curiously: "Xiaoxuan, what kind of brick-moving machine are you going to design? Can it be comparable to mine~?"
Li Zexuan stopped holding the charcoal pen in his hand and sneered: "Haha~! You have the nerve to show it to me with your crappy thing~? Just watch it from the side~!"
After that, he was too lazy to talk nonsense and began to concentrate on drawing.
Speaking of cranes, we have to talk about the pulleys on the crane. In addition to the hydraulic transmission mechanism, the most core and critical component of the crane is the pulleys. The fixed pulley serves as a fixed fulcrum to prevent the rope from being messed up, and the movable pulley mainly plays a role in saving force. As long as the pulley set is designed reasonably and properly, it is not uncommon for one person to pull a thousand kilograms of weight~!
"Let's build a simple crane first~!"
Li Zexuan had an idea instantly. A three-dimensional model of the crane's base, connecting rods, pulleys, lifting mechanism, and luffing mechanism appeared in his mind. These components, under Li Zexuan's pen, quickly formed a beggar with wheels. version of the crane.
There was no way. Although Li Zexuan could draw three-dimensional models of modern large cranes, most of them were hydraulic cranes. Even if he drew them, he couldn't do it with the industrial level of this era. Therefore, after much deliberation, we can only build a human-powered crane with a pulley block as its core.
"Is the painting finished now~?"
Seeing that Li Zexuan had stopped writing, Li Tai couldn't help but stepped forward and asked.
Li Zexuan nodded and said: "Yes~!"
Li Tai frowned and picked up the drawing. After looking at it for a long time, a trace of surprise appeared on his face and he praised: "This small wheel is well designed~! With this thing, the hemp rope will be used in the future." The wear and tear will be much less~! I no longer have to worry about the rope being worn~!”
Li Zexuan smiled half-heartedly and said: "Ha~! Not bad~! It's not easy for you to see this, Qingque~! But you only know one thing but not the other~! Tiedan, come here and take a look Look, what’s the use of the little wheel next to the connecting rod~?”
"Yes, Master~!"
Tiedan walked over as he was told and began to look at the drawings seriously. After a moment, he hesitated and said: "Master~! In addition to the small wheel at the top of the connecting rod, the one connected below probably has another mystery~!"
Li Zexuan glanced at Tie Dan with admiration and said with a smile: "Not bad, not bad~! Tie Dan, you are very accurate. Do you know the mystery of this little wheel~?"
Tiedan said embarrassedly: "Sorry, Master~! I can't see~!"
Li Tai muttered: "Isn't it just a broken wheel~! What mystery can there be~?"
Li Zexuan was too lazy to argue with the little fat man, so he pointed at the drawings and explained to them:
"Iron egg~! Qingque~! I call this small wheel a pulley~! The top one is called a fixed pulley. You can all guess its function, which is to fix the fulcrum, prevent rope chaos, and reduce rope wear. Below This pulley is called a movable pulley, and its effect is great, it can save half the effort~!"
Tiedan and Li Tai were shocked when they heard this and said in disbelief: "Save half the effort~? How is this possible~?"
Li Zexuan smiled calmly and said: "How is it impossible~? When using the movable pulley, the hook code is hung by two sections of rope. Each section of rope only bears half of the weight of the hook code. In this way, the person pulling the rope only needs to use half of the strength to pull the hook code. Go ahead~! When you study another course - physics in the future, you will know a theorem called power times power arm equals resistance times resistance arm.
The power arm of the moving pulley is twice as long as the resistance arm, so the power is half of the resistance~! At that time, if you use this theorem to analyze, you will find that the moving pulley is indeed labor-saving in principle. "
Although Li Zexuan's words contained many professional terms that Li Tai had never heard of before, the little fat man still felt that what Li Zexuan said made sense. He held his chin and fell into deep thought.
Tiedan nodded confusedly and said doubtfully: "Master, if it is like what you said, then if we use more movable pulleys, wouldn't we be able to lift several thousand kilograms of heavy objects with very little effort~"
Li Zexuan nodded approvingly and said with a smile: "Tiedan, you asked this question very well. Yes, theoretically speaking, it is indeed like this. Do you remember what I told you before~? Engineering has been developed to the extreme, ordinary people Anyone can lift a huge boulder weighing ten thousand kilograms, Master didn’t lie to you~!”
Li Tai's eyes widened and he was shocked and speechless. What Li Zexuan said was nothing more than fantasy to him, and it would not be an exaggeration to call it an immortal method.
But Tiedan nodded excitedly and said: "Yeah~! Master, I remember~! I didn't expect to see such a wonderful sight so soon~!"
Li Zexuan smiled, shook his head and said: "But in theory, the more pulleys you move, the less effort you have, but this also involves the question of whether it's worth it~!"
"What's not worth it~?"
Tiedan asked in confusion.
Li Zexuan said with a smile: "Although using the movable pulley saves effort, the distance moved by the power is twice the distance of the hook code, which means the distance is wasted, which involves the issue of efficiency.
For example, if you use a wooden stick to pry an ant, and if you use a wooden stick to pry an elephant, do you think the wooden stick is labor-saving or labor-intensive? The same goes for pulleys. It is definitely not cost-effective to use a pulley set that can lift a huge boulder to lift a basket of bricks. It is estimated that the pulley set is heavier than the bricks~!
Therefore, when deciding the number of pulleys, you must consider the actual situation, how big a horse should be, and how big a saddle should be, and don't do more useless work~! "
There were not many professional terms in these words, so it was not difficult to understand them. Tiedan and Li Tai both felt enlightened and fell into deep thought.
"I understand, Tiedan, thank you Master for your teaching~!"
After a long time, Tiedan came back from his thoughts and solemnly clasped his fists.
Li Tai also came to his senses, and he said seriously: "Tai also benefited a lot from listening to Mr.'s words. Thank you very much, Mr.~!"
Only then did he realize that what Li Zexuan said was right, the brick-moving machine he made was indeed a junky thing~!
……………………
