Commitment to domestic production! Hitachi's home appliance production line was Inspire the Next!

High-tech Hitachi production line up to the workbench (karakuri)

First of all, the canister type vacuum cleaner production line. This is what I am making.

Paper pack type vacuum cleaner "Karu Pack" with an interesting surface design (CV-KP900G)

The features of this vacuum cleaner are "lightness" and "power to suck in" in response to the persistent popularity of "vacuum cleaners are paper packs". The suction work rate, which is an index of suction power, is 340W, which is about twice that of a general cyclone vacuum cleaner.

It is an athletic-type vacuum cleaner that sucks in the sand dust hidden in the back of the carpet with power. The secret is that the flow of wind from the suction port to the paper pack and the suction motor is straight, and there is nothing to resist.

A straight line from suction to the motor. Ideal air flow The left is a commercially available paper pack that is leaking water, and the right is a genuine Hitachi paper pack. There is a small hole that does not leak water but allows air to escape. * Never inhale water with a vacuum cleaner.This experiment is just a performance comparison of the filter alone.

Commercially available paper packs leak water, but genuine Hitachi paper packs have extremely small holes that allow only air to pass through, not water molecules. The feature is that it can capture 99.999% of fine particles of dust together with this paper pack and filter.

Also, because it is straight and powerful, there is a concern that dust will collect in the rear part near the motor of the paper pack and the pack will be clogged with fine particles. If it is a general vacuum cleaner, it is time to replace the pack, but since Hitachi has a bypass of air that sucks from the front of the paper pack, there are places where the suction power does not drop until the pack becomes dusty. It's a feature.

Even if the part near the motor of the paper pack is clogged, Hitachi has a bypass (red arrow) for the air sucked from the front of the paper pack, so the suction power lasts a long time.

In addition, the diamond-cut design of the main body reduces the ribs (beams attached to the grid) on the back side and reduces the resin to make it lighter while maintaining the strength of the main body.

If you look closely at the cut, the basic structure is a triangle, so you can use a truss (combination of triangles) structure to disperse bending, pulling, compression and torsional loads, and increase the strength even if the wall thickness is reduced. Seems to keep it.

If you look closely, the diamond cut-like surface creates a beam-like skeleton to maintain strength while reducing the amount of resin that is composed of triangles and making it lighter.This skeleton is called a rib

Well, this is the site where such a vacuum cleaner is made.

This is the canister paper pack vacuum cleaner, all of the production line that makes light packs! Eh! Seriously !?

You might think, "Oh! It's so small !?", but this is a panoramic view of the production line! There aren't 100 more people on the left side of the screen, and there aren't hundreds on the other side.

Only this is compact because it uses a method called "cell production". Even now, there are many "line production" in which a long belt conveyor is installed in a building that connects several gymnasiums and is in charge of "one process per person".

This requires hundreds of processes and hundreds of people, including "only" people who install the motor and "only" people who tighten the screws. Moreover, the people who are working are not very interesting (laughs). On the other hand, it is the most efficient for mass production. Even if the work is automated by a robot, it is usually on-line production.

Although it is not a home appliance, it is a general line production site.

On the contrary, in "cell production", the assembly from the beginning to the end is done by one person. That's why it's interesting because there are changes in the work, and it's okay! Let's make it 30 seconds faster than everyone else today! It also helps maintain motivation. However, the problem is that you have to keep in mind how to assemble one vacuum cleaner. Therefore, it takes about one month of training to get to the production line and become a full-fledged person.

By the way, Hitachi's factory, where security is strict, is of great interest to people in the industry, so let's drop in on the workbench.

A workbench assembled with aluminum pipes.The shelf in front of you is a conveyor belt, and the necessary parts are delivered.

The first thing that stands out is not a ready-made workbench, but a "super" custom-made workbench that combines standard aluminum pipes (anodized in terms of texture). Normally, aluminum round pipes (PVC pipes for lighter products) are used, but mainly pipes with grooves for engaging clamps are used. Use a special pipe with ribs that has low resistance where you want to give strength or slide something.

The joints were also very abundant, and all were countersunk (the heads of the screws did not pop out) so that they would not be damaged by the fixing screws or the workers' clothes would be caught, and the unevenness was eliminated.

A pipe with a notch that can be clamped, etc. A pipe with ribs (knurled) that is used to support the structure of a workbench or to slide a little without using rollers.

The small parts are contained in the parts boxes provided on the left and right, and have an angle of about 20 to 30 degrees so that they can be easily taken out. Furthermore, on the right side, there is also a drawer-type mini table where parts can be temporarily placed. If you are making a product with many parts, you will probably put a parts box on this table as well.

It's also interesting to use a piece of pipe to make a pen or tool stand!

The side parts case is different for each one, such as an aluminum bat or one made by yourself. It was an empty box from a connector shop that I often use ... A toothbrush was stuck in a piece of pipe, probably for removing dirt.Some people have a pen here

This landscape may be uncomfortable for those who are accustomed to factory tours and those in the industry. Yes, the back side is strangely refreshing. Normally, the karakuri that supplies parts (generally a slope + roller, and the parts rack called "karakuri" from where the parts are drawn out one after another) are lined up on the back side, and the operator's hands are not very visible. However, Hitachi's factory supplies parts by conveyor from the front, so there is no karakuri of parts stock on the back side.

The parts stock in front of the workbench is a conveyor belt with several rows so that large parts such as the main body case, motor, cord reel (rewind type cord), etc. can be removed by the worker simply reaching forward. It has become.

In a general factory, work efficiency is poor because you turn around, but at Hitachi, you can take parts without taking your eyes off the workbench. It is also interesting that when you take out one part, the part will come out from the back on the conveyor. If you look closely, it seems that infrared rays are used to automatically detect whether the part is always in front of the worker.

In front of me, the cover on the top of the main body and the cord reel are pushed out on the green conveyor belt.It also serves as a parts shelf and is a karakuri of automatic parts supply.

Hitachi's cell production is not just about this. Normally, the back of the worker who sends the finished product is the passage of the automatic carrier that supplies parts. An infrared sensor detects that there are no parts in front of the worker, and an automated carrier runs to the cell and supplies the parts.

When there is a shortage of parts, Hitachi usually goes to the operator to check the number and manually replenishes the missing parts. Hitachi simply puts the parts in the specified lane of the parts carrier.Checking and replenishing the remaining number of parts is left to the computer

The person who puts the parts on the automatic carrier was the person, but the person in charge on the day was one person. In a general factory, the car in charge of parts supply walks around and replenishes the parts stock on the back of the worker, so a great deal of rationalization is made (in the case of line production, it is automatic up to the back of the worker). There are many places where transport vehicles carry parts, but in the case of cell production, many parts are supplied to one person, so it seems that there is a lot of human power).

In addition, since many kinds of parts can be loaded on the automatic carrier, it runs to the cell where the parts are missing, and the missing parts are sent to the worker's eyes by the belt conveyor. ..

When there is a cell with a small number of remaining parts, the transport vehicle automatically runs and replenishes the parts shelf in front of the worker with a belt conveyor.

Amazing is the time it takes to assemble. In the case of this vacuum cleaner, it takes an average of 4 minutes to assemble. Since it is an average, some people make it in the 3 minute range, so it is surprising that it can be made in a shorter time than line production if it is not good. It can be said that this is a rapid cell production line unique to Japanese people who have small hands and many dexterous hands.