"Giggle~! Iron eggs, do you still need to ask? Looking at Brother Qingque's expression, he must have failed~! I said that without my brother's help, he would definitely not succeed~! ”

Lan'er pointed at Li Tai and chuckled.

Exposing people is not short, Lan'er's words are not ruthless, and they directly poked Li Tai's heart, and the little fat man's face turned black, and he almost vomited a mouthful of old 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 look for you when I'm done~! ”

After that, he took the pen and paper in Li Tai's hand by the way, walked to the bookcase on the side and sat down.

Seeing this, Lan'er also understood that Li Zexuan was going to be busy with business next, and it was all something she wasn't interested in, so she said "oh" and went out.

Li Tai breathed a sigh of relief, leaned over and said curiously: "Xiaoxuan, what kind of brick moving machine are you going to design~?" Can it compare to my one~? ”

The charcoal pen in Li Zexuan's hand was stunned, and he sneered: "Hehe~!" You're embarrassed to take out that thing and compare it with me~? Just watch it from the side~! ”

After that, he didn't bother to talk nonsense anymore, and began to sink his mind and draw.

When it comes to the crane, we have to talk about the pulley block on the crane, in addition to the hydraulic transmission mechanism, the core and key component of the crane is the pulley block. The fixed pulley plays a fixed fulcrum to prevent the rope from messing with the role, the movable pulley mainly plays a role in saving force, as long as the pulley group design is reasonable and appropriate, it is not uncommon for a person to pull up a thousand pounds of heavy objects~!

"Let's get a simple crane first~!"

Li Zexuan instantly had an idea, and the three-dimensional model of the crane's base, connecting rod, pulley block, hoisting mechanism, and luffing mechanism all appeared in his mind, and these components, under Li Zexuan's pen, quickly formed a beggar's version of the crane with wheels.

No way, although Li Zexuan can draw three-dimensional models of modern hair cranes, almost all of them are hydraulic cranes, he just drew them, and he couldn't do them with the industrial level of this era. Therefore, after thinking about it, I can only make this kind of human-powered crane based on the core of the pulley.

"That's it~?"

Li Tai saw that Li Zexuan had stopped writing, and couldn't help but step forward and ask.

Li Zexuan nodded and said, "That's right~!" ”

Li Tai wrinkled his brows, picked up the drawing, and after looking at it for a while, a trace of surprise appeared on his face, and he exclaimed: "This little wheel is well designed~!" With this thing, the wear and tear of the hemp rope will be much smaller in the future~! I'm no longer afraid that the rope will be worn off~! ”

Li Zexuan smiled and said, "Heh~!" Not bad~! Qingque, you can see this, it's not easy~! But you only know one thing, you don't know the other~! Tiedan, come and see, what is the use of the small wheel on the side of this connecting rod~? ”

"Yes, Master~!"

Tie Dan walked over as he said and began to look at the drawings seriously, and after a while, he hesitated: "Master~!" In addition to the small wheel at the top of the connecting rod, the one connected below is estimated to have another mystery~! ”

Li Zexuan glanced at Tie Dan appreciatively, and said with a smile: "Not bad~!" Iron egg, you can see it very accurately, so do you know what the mystery of this little wheel is~? ”

Tie Dan said embarrassedly: "I'm sorry, Master~!" I can't see it~! ”

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, pointed to the drawings and explained to them:

"Iron Egg~! Green Sparrow~! I call this little wheel a pulley~! The top is called the set pulley, its role you can guess, is to fix the fulcrum, prevent the rope, reduce the rope wear and tear, the following pulley is called the moving pulley, its role can be great, it can save half of the force~! ”

Tie Dan and Li Tai were shocked when they heard this, and said in disbelief: "Save half of your strength~?" How is this possible~? ”

Li Zexuan smiled indifferently and said, "How is it impossible~?" When using movable pulleys, the hook code is suspended by two sections of rope, and each rope only bears half of the weight of the hook code, so that the person who pulls the rope only needs to use half the strength to pull it~! When you take another course, physics, in the future, you will know a theorem called that the power multiplied by the power arm is equal to the resistance multiplied by the resistance arm.

The power arm of the movable pulley is twice that of the resistance arm, so the power is half of the resistance~! At that time, you can use this theorem to analyze, and you can find that the movable pulley is indeed labor-saving in principle. ”

Although Li Zexuan's words contained many professional terms that Li Tai had never heard, the little fat man still felt that what Li Zexuan said was very reasonable, and he pinched his chin and fell into deep thought.

Tie Dan nodded ignorantly, and said suspiciously: "Master, if it is really like what you said, then if we use more movable pulleys, wouldn't we be able to lift thousands of catties of heavy objects with very little effort~?" ”

Li Zexuan nodded approvingly, and said with a smile: "Tiedan, you asked this question very well, that's right, theoretically speaking, this is indeed the case, do you remember what I told you before~?" Engineering has developed to the extreme, ordinary people can lift 10,000 catties of boulders, but Master didn't lie to you~! ”

Li Tai's eyes widened, and he was speechless in shock, what Li Zexuan said was tantamount to a fantasy for him, and it was not an exaggeration to call it an immortal method.

Tie Dan nodded excitedly and said, "Mmmm~!" Master, I remember~! I didn't expect to see this kind of wonder so soon~! ”

Li Zexuan smiled, shook his head and said: "But although theoretically speaking, the more moving pulleys, the more effort-saving, but this involves the question of whether it is worth it~!" ”

"What's not worth it~?"

Iron Egg asked curiously.

Li Zexuan said with a smile: "Although the use of movable pulleys saves effort, the distance of power movement is twice the distance raised by the hook code, that is, it takes the distance, which involves the problem of efficiency."

For example, using a wooden stick to pry an ant, and using a crowbar to pry an elephant, do you say that the crowbar is labor-saving, or laborious~? The pulley is the same, with the pulley block of hanging 10,000 catties of boulders, to hang a basket of bricks, obviously the pulley block is heavier than the brick, it is definitely not cost-effective~! ”

Li Zexuan said with a smile: "Although the use of movable pulleys saves effort, the distance of power movement is twice the distance raised by the hook code, that is, it takes the distance, which involves the problem of efficiency."

For example, using a wooden stick to pry an ant, and using a crowbar to pry an elephant, do you say that the crowbar is labor-saving, or laborious~? The pulley is the same, with the pulley block of hanging 10,000 catties of boulders, to hang a basket of bricks, obviously the pulley block is heavier than the brick, it is definitely not cost-effective~! ”

(End of chapter)