Sometimes, solved problems live their own, independent lives.
Not long ago, I visited Korea and heard an interesting story about a refrigerator home bar. I knew that solvers could not solve that problem for a long time. They were about to lose heart but decided to consult schoolchildren who ultimately helped them cope with it. I hardly recognized the problem we (Kim Hyo June and me) were solving in 2001. Though simple, it stuck to our memory.
Spring comes to Korea late in February. One just starts noticing that branches of the trees covering the mountains are growing pastel violet. This means that buds are swelling. And, all of a sudden, bushes along the roads become covered with small canary flowers which are called genari in Korea.
On a bright spring day, we, the TRIZ group of Samsung Advanced Institute of Technology, were going to the refrigerator factory in Gwangju. It was not our first visit to that factory. We already had some experience. During the year that followed the formation of our TRIZ group, we realized several serious inventive projects. Of course, the group would probably be putting it too strongly. The author of this article and the employee of the 6 sigmà department Kim Hyo June formed the entire contingent.
Mr. Kim was driving the car, smiling to his thoughts and singing quietly: “Nari, nari, genari…”. Dealing with the refrigerator factory was always an easy and pleasant job because we usually met not with managers but with practicing engineers. They usually understood the heart of the matter and could answer any of our questions. This time the problem definition was also extremely correct.
At this point, it would be useful to clarify what a Korean refrigerator looks like. It is a bulky box with doors opening to both sides. The left part is a freezer and the right part is the refrigerator itself. Any fridge has a very useful device – a “home bar”. The freezer doors are provided with a small window closed with an additional small door. The small door opens top-down and is held in a horizontal position by means of two diagonal rods so that a table is formed.
The formed opening provides an access to a small shelf isolated from the main fridge chamber by a plastic casing. The device is very popular because one can take a bottle of juice, milk or beer or a snack from the shelf without opening the big door and letting the precious freeze out.
How to reduce the fridge cost is almost clear: it is necessary to remove some components which perform unnecessary function. Though it looks simple, determining what exactly should e eliminated is not always easy.
Not this time, yet. The production group has already arrived at a conclusion that the most expensive elements are diagonal rods which support the small door in a horizontal position. Each diagonal rod includes two metal plates and three simplest joints joining these plates. Despite the simplicity, the manufacturing cost of a pair of such diagonal rods amounted to 7 dollars.
Our competitors also tried to use diagonal rods. LG (Dios) and General Electric invented a simple construction. Their diagonal rod is a plate provided with a joint at one end and with a pin, a sliding element, at the other end. When opening/closing the small door, the pin slides in the guiding groove. This looks much more aesthetic than three-joint diagonal rods. However, the cost remains high enough.
The reporter speech was flowing smoothly. Tearing, as usual, key words out of the information flow, I suddenly heard the word “children”. I did not understand at all why it was mentioned but I managed to catch the crux of the matter. Diagonal rods were no good and it was necessary to make them less expensive.
After unfolding to us all their problems, the engineers asked the main question: “What is to be done?” Well, the answer was quite clear –
it was necessary to follow the methodology!
- According to the ideality requirement, there should not be any diagonal rods at all, because the best diagonal rod is the rod that is missing while its function is being performed,” - Hyo June fired off.
- Then diagonal rods should be removed at all! –
said a calm man wearing a blue uniform.
«Well done! That’s practically all» –
I thought. –
«I hope they will not forget to include him in the patent…»
Yes, making the opened door bear against something behind the joint within the fridge will make diagonal rods unnecessary. What resources are available for system transformation? First of all, it is the shelf with beverages and snacks. A corresponding picture appeared on the whiteboard.
- Let us evaluate this solution! –
my manager said.
The team members were unanimous in opinion:
- The solution is bad because the shelf is positioned too high and taking beverages and snacks from the shelf is inconvenient.
What is to be done further? It is necessary to lower the shelf to its legitimate place.
Then contradictory requirements are imposed on the position of the small door itself:
• The back arm of the small door should be positioned below the shelf so that it can bear against something.
• The back arm of the small door should be positioned above the shelf because the shelf is installed below the opening for food products to be convenient to take out.
The contradiction is very simple and can be easily resolved in space. Really, it is absolutely unnecessary for the small door to bear against something throughout its width. To fix the door, it would be enough to provide a rest for the door edges. Then nothing will get in the way of bottles and cans.
On our way back from Gwangju we were thoroughly hiding our bewilderment from each other: the problem was so simple, easy-to-solve and the company's specialists were skilled enough… What prevented them from finding the solution? Yet, we did not think about it for long. It was the time when we had to prove the TRIZ and TRIZ group consistency at SÀMSUNG. Other projects displaced the fridge, the home bar and its door in our heads. But there still was a feeling that the story was not finished. And so it turned out to be.
When we came to Gwangju in connection with some other project, we asked about the home bar door fate. They answered that the solution was not accepted because it did not meet the safety requirements. According to those requirements, it was necessary that three babies, who could suddenly decide to hang on the door, did not break the mounting. Three babies because the door had three sides to hang on. The team’s opinion was that the side rests could not provide such strength.
We asked to organize a meeting with the team. At the meeting, only one question was asked:
– Just imagine that three naughty babies jump on the door and hang on it. The door endures the load but the fridge falls on them! This case is much more dangerous than damaged noses, isn’t it?
After a moment of silence, proposals came in showers. The final solution was as follows: it is necessary to select such an effort the door should withstand when in horizontal position, that an adult man bearing on the door with his elbows cannot break it. And in case of an excess effort, impact or the like the door should not break but should fold downward. Such a door, which does not basically differ from the proposed one, was introduced in the design of all Samsung refrigerators.
|SAIT TRIZ group of the period of work on TRIZ-trainer, 2002. From left to right: Kim Hyo June, N.A.Shpakovsky, V.A. Leynashin, E.L. Novitskaya. |
That short meeting revealed much to me. Altshuller justly paid so much attention to the overcoming of mental inertia. While watching the team, I was trying to understand what had prevented the specialists from solving the problem by themselves. A cage, a mental cage… Every man unintentionally builds a psychological wall of limitations around themselves and carries a problem to this cage for solving it quietly. Once built, such a wall turns out to be very strong. Going beyond this voluntarily constructed virtual cage and understanding that any limitation can be easily specified or changed is not easy. As to the home bar door, the problem was created by vaguely formulated limitations and not by the search for a method of attaching a door without diagonal rods. The specialists could undoubtedly solve this problem by themselves and our help was minimal. Still we can say that consultation took place.
By the way, our efforts were appraised and soon the TRIZ group received a “parcel” from Gwangju – a refrigerator of a new design with a wish: Invent the new and send it to us!
And we acquired one more scintilla of experience: “A problem is not a fortress, mark the borders, but don't build fences”.
* * *
Not long ago, I met Kim Hyo June in Suwon, in a huge, noisy supermarket. We saw rows of fridges there, including Samsung fridges with a small door of our design. Hyo June came up, opened and closed the home bar several times, nodded and sang quietly: “Nari, nari, genari…”