This serial article has reached tenth posting. It means that ten years have passed since we launched Motiontite (trademark registered). We'd like to express our heartfelt appreciation for adoption of Motiontite in various industrial sectors and supports of many people in these years.

I became interested in anti-loosening screws about thirty years ago. I remember that the mainstream technology at that time was anti-loosening nuts, there were only a few technologies performing anti-loosening with a male screw alone, and most of the anti-loosening technologies were prevailing torque type products.

In those times, I simply thought that loosening could be suppressed by forming a structure to bring a male screw and a female screw into contact with each other, and tried several thread shapes of a friction contact type. Screws didn't loosen even when the screws underwent tests using a vibration test machine. However, tightening and untightening of the screws were laborious. The larger the screw diameter, the more difficult filling a gap between the male screw and the female screw. As a result, we dropped development of them.

Next, we tried a product, in which a right-hand coarse thread and a left-hand fine thread are machined simultaneously, for preventing loosening with right-hand and left-hand double nuts. We exhibited the product under the name of "Symmetry Bolt" in exhibitions in the United States and so on. However, it was difficult for visitors to tighten the left-hand fine thread nut properly, so we determined that expansion of sales was difficult and gave up the sales of it.

What we tried the last time was the shape leading to present Motiontite. We sticked to a strong anti-loosening power and a high workability. What thread shape would be optimum for preventing loosening by simply tightening in a normal way? We made two hundred or more dies and repeated vibration test, fatigue test and tension test. The product completed by doing so is present Motiontite.

Motiontite is a splendid product that satisfies the mechanical properties of the screw stipulated in JIS and ISO and enables precision management of threads with ring gauges.

Our story of development will continue from Motiontite to "TRIBO" and further to "Hollow Set."

When I explain about "Motiontite" in front of customers, I make sure to explain, "Motiontite is the screw that can inhibit loosening, breakage, and seizure just by being tightened normally." I always emphasize its improved workability as well as possibility to preclude the three biggest claims about screws, "loosening, breakage, and seizure." Since Motiontite has the very same workability as ordinary screws, currently-used screws can be replaced with Motiontite. If you have any troubles with "loosening, breakage or seizure," please feel free to contact us any time.

This year, we're planning to sell screws enabling downsizing of bolts. Necessary conditions among conditions for downsizing the bolt are, firstly, not loosening, and secondly, maintaining a tightening force (axial force) of the bolt before downsizing.

The above two conditions are satisfied by combining a high-strength material of the strength class 13.9 and the strong anti-loosening force of "Motiontite," thereby enabling downsizing of the bolt. Thus, the number of the bolts can be reduced, and the size of the bolts can be unified, whereby workability can be improved. Further, downsizing of parts can be realized, which contributes to weight reduction and downsizing of a product itself.

For example, please imagine what happens if M14 bolt can be replaced with M12 bolt, M12 bolt can be replaced with M10 bolt, and M10 bolt can be replaced with M8 bolt. Since plating can also be applied, it can be said that Motiontite is the optimum screw for products, of which weight reduction is required.

It took a long time to develop a new thread shape for combination with the high-strength material, but pains of development are blown away when considering infinite potential of this product.

I'll never forget my feeling when I gently clenched my fist with joy in front of the Junker vibration test machine.

"Bending thread just a little", an idea which can be said to be the structure of Motiontite, improves performance of a bolt dramatically. It inhibits concentration of stress on the mated first thread and averages load share rate, so breaking off of a screw head, buckling, damage to a female thread and partial contact are resolved. In addition, anti-loosening force and fatigue strength improve, and seizure can be prevented.

Motiontite is also employed as a bolt for an internal combustion engine. In the case of a regular bolt, if temperature of the bolt increases during durability test and the like, the bolt bulges and extends so that axial force lowers and the bolt becomes more likely to loosen. As contrasted, in the case of Motiontite, if it bulges, springing reactive force and frictional force increase, whereby Motiontite becomes less likely to loosen. This has been verified by the fact that Motiontite has higher loosening toque after the durability test than the regular bolt.

Last year, we accepted orders in a wide range from M2 bolt to M30 bolt. We're really thankful for employment of "Motiontite" as countermeasures against loosening and breakage. It is the greatest joy for the developer to receive appreciation for prevention of loosening and breakage from customers who have become users. Cherishing this voice, we are eager to expand the stage for "Motiontite" to the world.

"Motiontite" has a structure exerting an axial force, which is equivalent to an axial force exerted by an ordinary screw, with a tightening force, which is higher than a tightening force for the ordinary screw by 10 to 20%. Naturally, "Motiontite" has high loosening torque, which by itself explains why loosening can be inhibited.

Because of excellent features of "Motiontite" such as anti-loosening, anti-breakage even under a vibration load increased by 20% and a capability of obtaining a stabilized axial force, a higher axial force setting is enabled. Thus, if downsizing of a bolt is enabled, the price and the weight of the bolt will reduce, and accordingly, the prime cost will reduce significantly. The number of tools can be reduced by unifying two kinds of screws into a single kind of screw, thereby improving on-site workability. Furthermore, by reducing the screw length, tightening objects can be made thin and light, and a tapping hole can be shortened. In this way, considerable benefits can be gained such that designers' laboriousness for chipping away each gram can be blown away.

In ten years' time, vehicle electrification will advance worldwide. To hold a large-capacity battery, reduction in weight will be required more than ever.

If an innovation of reduction in weight could be achieved in the field of elemental technology, which has been said to be unchangeable, the world of manufacturing would be changed fundamentally.

We continue research and development, maintaining enthusiasm not defeated by COVID-19.

"Motiontite" is excellent in die-cast aluminum tightening. An ordinary screw, in which pulling occurs between a contact seat surface and mainly three tightened threads among entire threads, can suffer a collapse of the contact seat surface or deformation of a female screw on the die-cast aluminum side. "Motiontite," in which a load is distributed over an entire range of fit, can perform more balanced tightening than the ordinary screw, in which the load concentrates in the three threads.

Last year, we successfully entered into product sales contracts with one company in Taiwan and another company in Vietnam. Thus, we could bring "Motiontite" to overseas at last, but overseas deployment of new products is still quite a challenging task. In anticipation of deployment in Europe and the United States in the future, we wish to appeal its performance more and more.

Now, this year's target is to develop "anti-loosening self-tapping screws." We tackle new subjects every year. Especially we're excited now because this is the first time for us to develop the self-tapping screws. The self-tapping screw has a high freedom of design, which will allow us to design adventurous shapes of the self-tapping screws advantageously. Its design concept is the same as that of "Motiontite," and is about how to make it possible to pull an axis. The screw having the axis pulled correctly would not loosen easily. This fact taken for granted is actually the most difficult, but we expect we can make it based on our experiences up to now.

Someday, various kinds of "Motiontite" serve as de facto standards of markets and prevent accidents caused by loosening of screws. This is our motivation for the development.

In the past one to two years, we have had more and more opportunities to receive inquiries from major companies about loosening or breakage of a screw. Obviously, the loosening or the breakage necessarily has its causes. Most of the causes are related to variation in the axial force, but there are also cases where the causes cannot be specified easily. The latter cases include, for example, a case where the cause is a partial contact of the screw, and a case where the cause is low accuracy of a tapped hole on the internal thread side.

Motiontite (trademark registered) having a structure, in which the threads are tightened while deforming elastically, exerts a great effect upon the loosening or the breakage caused by the variation in the axial force or the partial contact. A load is distributed among all the threads in Motiontite as contrasted to ordinary screws, in which a load concentrates on three tightened threads. Accordingly, Motiontite not only provides a stable axial force but also exerts an overwhelming anti-loosening power because of an elastic repulsive force from the threads, among which the load is distributed. If you have any troubles related to the loosening or the breakage of the screw, please try Motiontite.

We are now developing a thread shape largely improving fatigue strength. A shape capable of achieving approximately 1.5 times as high fatigue strength as the ordinary screws is nearly completed. Already marketed Motiontite provides approximately 1.2 times as high fatigue strength as the ordinary screws. By obtaining higher fatigue strength, a bolt can be downsized, whereby realizing weight reduction and significant cost reduction. Whereas the present Motiontite brings the external thread tip first into contact with the internal thread, newly developed one has a shape causing the external thread and the internal thread contact each other in parallel as in the ordinary screws.

Work for narrowing down the shape out of infinite possible shapes is a daunting task, but it is also accompanied by a great joy. The spirit of manufacturing exists therein.

Motiontite (trademark registered) having more equalized sharing of load among threads than ordinary screws exerts a strong anti-loosening force and has improved fatigue strength. Especially, Motiontite exerts an overwhelming anti-loosening power more in the case of a screwed bolt (bolt-tap tightening) having long fitting length than in the case of a through bolt (bolt-nut tightening) having thread fitting length restricted by the number of the threads.

Motiontite inhibits seizure by releasing a frictional heat on contact surfaces using an elastic effect of the threads and is less susceptible to an effect of elastic interaction, which can cause reduction in an axial force. Thus, Motiontite is a product that addresses the problems related to the bolt tightening.

Further, the elasticity of the thread provides many advantages such as reduction in variation of the axial force, alleviation of uneven contact of the threads, and the like.

In addition, what I want to emphasize most is that Motiontite provides the very same workability as the ordinary screws. Work with Motiontite can be completed by tightening in a normal way with an impact wrench, a nut runner or the like. Motiontite completes the anti-loosening without the use of any special nut or washer or any adhesives.

I think that Motiontite, which does not loose easily even with a little tightening error, might be the only product that can facilitate the screw tightening management in the production plants.

Motiontite (trademark registered) does not bring flank faces of a male screw and a female screw into contact with each other in a state where they are parallel to each other. Rather, Motiontite has a structure to make the flank face of the male screw contact the flank face of the female screw gradually from the thread tip of the male screw. Thus, by slightly increasing elasticity of the thread, innovative functions such as "strong anti-loosening force, high fatigue strength, stable axial force and seizure prevention," which conventional screws could not achieve, are now brought about.

Up to now, Motiontite has exerted the anti-loosening force in the case where the material of the female screw is iron or the like. This year, we're going to test the possibility of Motiontite to exert the anti-loosening force also in the case of plastic materials such as GFRP (glass fiber reinforced plastics), CFRP (carbon fiber reinforced plastics) and the like, which are indispensable for weight reduction. It has been pointed out that tightening of a bolt to FRP has a defect that FRP degrades when temperature increases, thereby causing extreme lowering of the axial force. Regarding this, we estimate that such extreme lowering of the axial force would not occur if surface pressure could be reduced by optimizing a contact area of the thread and by increasing the elasticity of the thread.

Every year, new challenges arise. Loosening of the screw (lowering of axial force) can be caused not only by slipshod tightening management but also by just small environmental changes. There are lots of causes for the loosening such as changes in frictional coefficients due to differences in the material of the male screw, the material of the female screw and surface treatment. Development of Motiontite goes on, aiming at "the screw that can suppress the loosening by easy tightening by anybody."

Two years have passed since we launched Motiontite (trademark registered). Last year, we got more and more business partners, and Motiontite was employed by more and more major companies. It could be said that last year was literally the first year of selling. Motiontite was often employed as an important part. We think that the features of Motiontite - the price almost the same as standard goods and the performance overwhelmingly superior to the standard goods - have been appreciated. Also, we are grateful as the spread of Motiontite is also a fruit of selling efforts by our business partners.

Our development target of this year is to improve fatigue strength of an aluminum bolt, which has been considered as the most difficult task. Aluminum bolts have come to be increasingly employed in automobiles in Europe for weight saving. Such trend is accelerating also in Japan. If the fatigue strength of the aluminum bolt giving anxiety about strength could be improved, it would contribute largely to improvement of gas mileage, too. We expect that spread of Motiontite to overseas will accelerate if the features of anti-loosening and break-proof of Motiontite can be applied also to materials such as aluminum.

Last year, "Shitamachi Rocket," a drama depicting a small business battling against a big business, attracted tremendous attention. As in that drama, some day, Motiontite might be employed in a rocket for real. To be prepared for that day, we continuously make efforts to improve the performance of Motiontite.

When vibration test (NAS3350) is performed by tightening a normal screw with standard torque, it does not loosen easily in the case where the screw is a heat-treated bolt of strength class 8.8 or higher. However, for example, if vibration test of one-hundred screws is performed, there is a possibility that about one or two screws loosen early because of variation of an axial force. Manufacturers use adhesives or locknuts because of the loosening of the only one or two screws. Naturally, a cost will increase significantly as the number of the bolts increases. Nevertheless, today's trend of the public that seeks the safety is that the manufacturers should respond if there is a possibility of the loosening of only 1%.

Motiontite (trademark registered) is the product developed to eliminate the 1%. Variation of the axial force of Motiontite is about 1/2 of the standard product. Therefore, an extremely lowered axial force, which is a cause of loosening, is not applied. Further, Motiontite exerts a high anti-loosening power with an elastic force of a thread bending slightly.

There is no screw in the world that never loosens under any conditions. Even if abundant time and cost are invested in the future, development of such screw will not complete forever. However, there have been lots of screws that do not loosen under certain conditions. If Motiontite is the screw having the largest number of alternatives of the "certain conditions", the developers of Motiontite couldn't be happier. We really hope that Motiontite comes to be known to as many of you as possible and that you will have an experience of such the convenient and high-performance screw.

A versatile screw should be usable for everybody with ease at low cost. Otherwise, it would be pointless. We continue manufacturing of products with higher performance, hoping that Motiontite will be introduced as the most reliable screw all over the world in the near future.