Combined with the visit to the vehicle factory, we hope to know a few things in today's article: what is TNGA we have been talking about and what is its use in manufacturing? And some technical details of M20C engine. Because the visit time is limited, and photos are not allowed in the whole process, the pictures in this article are all from official maps and past content materials.
Is TNGA architecture significant?
Toyota has been implementing TNGA architecture for five years since the fourth generation Prius of 20 15. Almost every article about Toyota will mention TNGA, so what is TNGA?
In the past, we had to get the design done first, find problems in the production process, feed back the design, polish it step by step, and so on, and then go to the manufacturing process.
So the biggest significance of TNGA architecture lies in product development. Based on the same architecture, Toyota can quickly develop a variety of models with different wheelbase and different types, so that the advantages of previous models will shine.
TNGA？ M20C engine
People who love engine technology or Toyota brand must be very familiar with the latest 4 1% thermal efficiency TNGA engine. Today, we finally saw how this engine was produced.
The "self-destruction" here is worth mentioning. Does not mean that workers are basically not required to operate. More importantly, there is a perfect problem monitoring mechanism to prevent the outflow of defective products by detecting various abnormalities.
The production line we visited is M20C engine, which is a traditional gasoline-powered vehicle with 2.0L displacement in Toyota TNGA engine. In my opinion, it almost combines the mainstream cutting-edge engine technology.
Mazda's Atkinson cycle and the intake manifold/in-cylinder direct injection hybrid injection technology that we have seen most on Volkswagen EA888 engine both appear on this generation of Toyota TNGA engines.
We try to connect these technologies in series to explore the origin of high thermal efficiency. Atkinson cycle (actually called Miller cycle) is simply to adjust the valve opening and closing time through electronic control valve technology (VVT-i of Toyota housekeeping).
As shown in the gif diagram above, under the low load condition without too high power, we let the valve close a little later at the end of the intake stroke (using the VVT technology of Toyota housekeeping), so that at the beginning of the compression stroke, the mixture in the cylinder will "spit back" a part from the intake.
Because there is a short period of "exhalation" in the compression stroke, there is actually not so much mixed gas. Naturally, there is no such high actual compression ratio in the cylinder after compression, and there is no excessive pressure that may lead to deflagration.
The faster the flame propagates, the more fully the mixture burns in a limited time. The TNGA engine is annular and exquisite. Combined with some minor improvements, such as using electronic thermostat and electric water pump to form a variable cooling system to optimize the temperature control performance of the engine; The "small progress" brought by miniaturization and lightweight components is also an indispensable part of 4 1%.
Of course, our analysis of TNGA engine from the technical and strategic point of view is nothing more than a few words, but it is the result of engineers' research, test, improvement and repeated verification day and night.
Back to the factory, I didn't visit the foundry because of time, and I didn't see the low-pressure and high-pressure casting equipment of the cylinder head and cylinder block. However, in the processing workshop, we found that the equipment quantity of GTE processing workshop is only about 1/3 of other brand powertrain factories.
After rough machining, honing crankshaft hole and cylinder hole (similar to fine grinding of cylinder wall) are two important high-precision machining processes, the precision of the latter is 0.0 15 mm, and in the cleaning process after finishing machining, the foreign matter in the oil passage should be below 5mg, which are the standards of the factory.
An engine is officially manufactured after final assembly, but before delivery, some tests, including manual tests, are needed to confirm the job completion information with TCR disk.
Vehicle manufacturer
Friends who pay attention to the technology channel should have seen many automobile factories here. Stamping, welding, painting and assembly are almost universal process specifications all over the world. The trip is hasty and filming is not allowed, so I won't go into details here. Here, I'll pick a few highlights to talk to you.
Guangzhou Automobile Toyota Automobile Factory has a high degree of automation, and AGV automatic transport vehicles are responsible for the logistics of each workshop. The stamping equipment is made by Komatsu in Japan, and the maximum production capacity of a single C-class line can reach 30 pieces/minute.
In the welding workshop, we saw a patented technology of Toyota-electrode tip sharpening stone. Every time the robot in the welding workshop completes welding, the electrode head will be polished in the forming machine to ensure the consistency of each work.
There are four groups of motors welded and positioned on the floor of the car body, and the fixture accuracy is 0.05 mm After welding, there will be a mechanical arm to carry out standard measurement on 32 parts.
In order to improve the efficiency, the factory has developed a portal transportation channel, which can automatically transport the required materials by manual or robot, and the execution efficiency is very high.
Through the assembly workshop, the whole vehicle is basically assembled, and each quality inspector of the inspection line will bring an iWatch in his hand. After the inspection is completed by comparing the serial numbers, the inspector can directly click on the watch to confirm and generate an inspection record.
In addition, some inspectors will also hold an iPad in their hands. They are the people who check the vehicle configuration. They can compare the pre-generated configuration charts one by one.
In the final inspection, each car has to run a "small runway", including a stone road (Belgian road), an asphalt road bend and a bumpy section with steel wires to test the assembly, abnormal sound and driving functions, and then enter the shower room for rain leakage test.
In addition to routine inspection contents, GAC Toyota also has a legendary "black hat" team, which is responsible for sampling inspection of assembled vehicles. They have Toyota's most stringent testing standards, and will update this standard year by year according to customer feedback. Before, my colleague Xia Zhimeng made an issue of Apprentice, which introduced the quality inspection of Toyota in detail. I also put the video here for everyone to see.
More exciting videos are on car home Video Channel.
abstract
The material is limited, and some things I saw with my own eyes may not be visible to you, so I can only describe them in words. In GAC Toyota Vehicle Factory, there are many AGV automatic vehicles, high-tonnage stamping equipment, mechanical arms and other equipment, but the patents and self-developed equipment such as electrode grinding stones can still make people shine. In contrast, GTE engine factory still fascinates me more, which is one of the reasons why I put GTE factory and TNGA engine in front. Thank you for seeing this. I believe you have a certain understanding of GAC Toyota's vehicle and engine manufacturing plant. Let's reveal it next time. (Figure/text? Car home? Zheng Xu)