What Hoffman experienced this winter also happened in the villages in Wesson and surrounding areas, including his search for a wife.
At the beginning of the new year, the soldiers at the border checkpoint were surprised to find that there were many more people coming to Wesson, most of them young people, many with their families.
At this time, Frederick was testing the clutch with Schmidt and others. There was a problem with this gear clutch. The gear could only be shifted after the gear rotation stopped, otherwise the gears would be beaten and the gears would be damaged.
Frederick had no good solution for this, and the gearbox was also like this.
Research on gearboxes has also promoted the development of gears. Gears require good tooth contact strength and wear resistance, and the gear teeth are required to maintain relatively high toughness, which puts forward higher requirements for processing.
Then Frederick discovered that he had forgotten the differential, and the bevel gear in the differential that he had seen in his previous life was too difficult to process with current technology.
He thought for a long time, and finally recalled that there seemed to be such a spur gear differential, which used ordinary gears and could work well with the chain drive.
The differential designed by Frederick has a mooncake-like housing, and a chain or gear drives the housing to rotate. The gears at the top of the two axles are inside, and multiple pinions are set on the inner side walls to mesh with the axle gears here.
, like a big circle with several small circles around it.
When the housing rotates, the pinion drives the axle gear on this side. Under normal circumstances, the internal pinion and axle gear are relatively stationary. When the axle speed on one side slows down or even stops, the pinion on this side will rotate.
He made a model out of wood and existing gears, but it failed because if the load on the axles on both sides was greater, it would cause the casing to spin.
Failure is not terrible. The elders said that everyone will make mistakes, but engineers must analyze the causes of mistakes.
Frederick studied for two days and finally discovered where the mistake was. He had remembered it wrongly.
This differential is generally correct. There is a problem with the internal pinion gears. They need to be arranged in a "" shape when viewed from above and a "" shape when viewed from the side. The left and right ends engage the two axle gears respectively, and the middle end
bite each other.
Viewed from the side, when the axle gear rotates clockwise, the upper pinion rotates counterclockwise. When the gear rotates counterclockwise, the right side goes up and the left side goes down, so the two side by side pinions with the same rotation direction are stuck with each other.
When the load on both sides of the axle is the same, the two pinions will act like a whole and drive the axle gear to rotate.
Assume that when the load on one side of the axle increases, the corresponding axle gear stops rotating. If the clutch moves clockwise at this time, the pinion gear on the stopped side will rotate clockwise around the fixed axle gear, and it will also rotate clockwise, driving the
The adjacent pinion rotates counterclockwise, which then drives the rotatable axle gear on the other side to rotate clockwise.
Although it is rare that one side of the axle is locked and stalls, and the speed is just slowed down, from the mutual motion, it can also be seen as that side of the axle is stalled, and the differential will work.
The new spur gear differential was ready. We installed it on the stand together with the carriage's axle and wheels, and then connected it to a newly modified two-cylinder steam engine through the newly made chain.
As the cylinder starts, the two wheels immediately rotate rapidly. A lever is installed on the outside of the wheel, which triggers a counter every time it rotates.
Five minutes later, a student reported to the principal that the wheels on both sides rotated at the same speed.
Frederick nodded and asked them to proceed with the next test.
Soon, a student took a wooden board and pressed it on one wheel to increase its load. The wheel speed on that side slowed down a lot, while the wheel on the other side not only did not stop, but also turned faster.
Everyone breathed a sigh of relief, another problem was solved.
Next, there is a more troublesome task. Assembling various systems together is also a skill. If you don't do it right, the light weight will be too heavy, and the heavy weight will fall apart.
Frederick asked Benz to make models of the same size according to each system. The steam engine, condenser and water tank were empty wooden boxes, the chain was a hemp rope, and the flywheel was directly modified from the soup bucket lid that was bitten by rats in the canteen.
Wait, as long as they are the same size, then a group of people use their brains to build building blocks.
Then a problem arose. The chassis of the steel frame carriage was not suitable for tractors, so Frederick began to calculate the weight and position of each system. He referred to the truck chassis he knew and "I was thinking" about coming up with one that at least would not be crushed.
The chassis comes out.
In the final assembly stage, various problems emerged one after another. In order to facilitate riveting, the original assembly plan was overthrown and restarted.
In the continuous cycle of problems arising - analyzing problems - solving problems - summarizing experience, the steam tractor took shape bit by bit.
What followed was a variety of documents weighing more than a tractor in the archives, which recorded in detail the results of every experiment and every process detail.
Frederick specially arranged for someone to compile them into a book, which would be useful if he traveled through time again one day.
One day in early March, Frederick deliberately asked Benz: "How many days are expected to complete all assembly?"
Benz opened a thick notebook and recorded the parts of the entire tractor, ticking each one after it was installed.
"There are still three days," he replied. "In three days, all the instruments will be assembled, and then we will start adding water and testing the machine without load."
Frederick nodded and said, "Just watch over the next few days. I'm going to see how the farm tools are being made. I'll send them over when they're done, and then I'll go do some other things."
The agricultural tools used with the steam tractor were researched and produced at Bryant's blacksmith shop, and Frederick sent a group of experienced farmers to help.
Frederick felt at ease with this master blacksmith. He had participated in many innovative projects and he didn't have to worry about it, so he rarely went there.
Bryant lived up to his trust, and the plow, planter, furrower and wheat harvester were all ready.
Frederick squatted in front of a few farm tools that had been brought out, and studied them with great interest.
Although he has issued a slogan for more plows and rakes, the current one is only a 20-horsepower steam tractor, which can only drive one plow for deep plowing. For shallow plowing, it can use more plows than the current plows.
With the current level of agriculture, the depth of farmland is generally only about 10cm. After all, it is enough to sow wheat at 3 to 5cm, and the depth of plowing is less than 20cm, and it is only plowed once every four or five years.
The cultivated layer of land without deep plowing is more than ten centimeters thick. Below it is the compact plow bottom layer. This layer of soil is dense and relatively compact, which will hinder the penetration of water, ventilation and the growth of crop root systems.
The deep plowing mentioned by Frederick is more than 30 centimeters, which is of great help to improve the physical properties of the land, increase the available soil moisture, eliminate weeds, increase nutrients, promote the growth of microorganisms, and improve the development of crop root systems.
His hometown conducted a survey in 14 counties and cities including Chang'an and Baoji in the 1950s. The wheat yield of farmland cultivated to a depth of 36 to 40 centimeters increased by more than 40% compared to farmland cultivated to a depth of 10 to 20 centimeters.
So Frederick was very satisfied after measuring the size of the plow with his hands. With the development of technology and the popularization of deep plowing, grain production could reach a higher level.
Another thing that can improve work efficiency is the wheat harvester. It can be towed behind the tractor and is powered by wheels on the ground. The wheat dialing wheel protruding from the side can turn the wheat towards itself when rotating. The double-layer saw teeth below
The back and forth motion can cut the wheat straw, and the conveyor belt at the rear can send the cut wheat to the other side of the tractor, where a carriage can follow and wait for the wheat and wheat straw to fall into the vehicle.
After looking around here, Frederick was very satisfied. He calculated the dates in his mind and thought that he could try the power of steam tractors for this year's summer harvest and autumn sowing.