Philip Lutolf HP1 – The World’s First Mechanical Wrist Watch with Helicoidal Springs

A Swiss mechanical engineer named Philip Lutolf created the world’s first Helicoidal springs powered mechanical watch HP1 in 2008 after conducting several years of research and development, tests and prototyping. He has also created his own label Lutolf Philip to commercialize the production of this wristwatch in strict limited editions.

It all started with pure fascination for watches and their highly complex and ancient mechanical movements. Out of this admiration arose the curiosity to understand why the basic principles of mechanical watches remained the same for over five centuries. This simple question initiated a process of thought which led to a patented invention. The invention, “Helicoïdal Constant Force”, is based on a new technical concept to measure time. It is a new mechanical movement that no other watchmaker has ever worked on.

The H-Power movement (Helicoïdal) differentiates itself from the established mechanical movement by the following characteristics:-

Helicoïdal Springs: For the first time in history there is now a movement which is powered by Helicoïdal springs.

The Turbo:  The H-Power movement is an entirely new concept. It integrates several mechanical units which can sense and control the torque. This enables the watch to function with unparalleled reliability. The Helicoïdal power is used on demand to enhance precision and to assure best performance with additional complications.

Hi-tech Materials: The maximum power of a Helicoïdal spring is about 20 times greater than a spiral spring. It was observed that, after passing several mechanical stress tests, that only special technologies and material could be used to withstand the pressure and improve the overall efficiency of the movement. The steel of the wheels was replaced by a special material named “Strongnium® Diamond Carbide”. The traditional watch jewels (rubies) were replaced by specially engineered Ceramic Bearing Wheels and titanium nitride was used for optimum power delivery of the Helicoïdal springs.

Ultimate Complication:  The H-Power movement is a highly complicated and fine-tuned system. Two opposing principles must be brought into line. On one side, it has to deliver tremendous power from the Helicoïdal springs. On the other side, it has to deliver the right power at the right time with high reliability and without disturbing the running of the movement. A low powered mechanism has been installed precisely for this function. This is why the H-Power calibre has over 200 more parts than the traditional movement . The HP-1, the first timepiece having a H-Power calibre, contains more than 800 components.

Traditionally, all mechanical watch movements use spiral springs. All watchmakers consider them as the noble spring due to their unique mechanical characteristic, which is a relatively flat and low torque curve. This is considered ideal for a watch movement.

Contrary to this, the helicoïdal-spring, which is a coil spring, has a linear and fast increasing torque curve when used in compression. This is still considered today as non-functional for a watch movement. The HP-1, (Helicoïdal Power), is the first wristwatch in the history of watch-making that integrates coil springs in its movement.

The maximum power of a helicoïdal spring is about 20 times greater than a spiral spring. One of the major challenges of the development was to manage this extremely high power in a watch movement where the teeth of the wheels and pinions are often less than a millimetre long.

Without extensive research on material, coating, dynamics and tribology (the sciences of friction), the manufacturing of this movement would not be possible. A watch with the HP-movement exists today because Swiss technology can offer quality solutions to match the physical demands posed by this new power source. New materials have to be used to reduce friction, to ensure reliability and to increase overall performance.

Lutolf’s research concluded that only a special carbide could withhold the pressure in the teeth of the wheels and only bearing wheels would be suited for the radial pressure in the axle. After passing several mechanical stress tests, a carbide mixture that was never used before in the watch industry was defined. It is known as “Strongnium® Diamond Carbide”. To resolve the radial axle pressure and improve the overall efficiency, we had to replace the traditional watch jewels (rubies) by specially engineered Ceramic Bearing Wheels. Finally, titanium nitride was used to produce the Helicoïdal springs to assure the optimum power supply to the system.

The finding of innovative materials and new technologies were the necessary steps to assure the meticulous functioning of the core: the HP-movement. This patented invention, “Helicoïdal Constant Force”, is a remarkable combination of helicoïdal and spiral springs.

It is a very complicated and fine-tuned mechanism in which two opposing principles must be brought into line. On one side, the helicoïdal springs deliver tremendous power to the movement. On the other side, a specialized mechanism has to deliver just the right power at exactly the right time and with high reliability without disturbing the running of the movement.

This patented invention is based on:-

• Helicoïdal titanium nitride springs

• Linear high strength regulator

• Strongnium diamond carbide wheels

• Ceramic bearing wheels

• Automatic torque control system

• Bi-planetary differential

• Instantaneous double escapement trigger.

Because the results of physical law are not the same for the H-Power mechanism as in a normal spiral spring watch movement, the mechanics had to be specifically developed. This is the reason why, when you look at the movement for the first time you cannot classify it like all other watches in the two known categories: manual or automatic movement.

The outstanding achievement of this complex system is a completely new approach to keep the torque constant. At any time it guarantees a constant torque at a selected level. A high and constant torque is the ultimate goal for optimum performance and precision of a watch. These characteristics are especially needed when complications are added to the mechanism.

The idea is to make sure that the spring barrel always delivers the same torque level to the escapement.

The following process assures this success:

1. The power that is generated by the Helicoïdal springs is transmitted to a mechanism which is called the “Linear High Strength Regulator”. It is responsible for decreasing the power by a calculated factor and transmitting it to a gear train which will rewind the spring barrel to the optimum power.  New materials and innovative technologies plays a key role in this process where the ceramic bearing wheels and the wheels of Strongnium® Diamond Carbide have to cope with the tremendous power delivered by the four Helicoïdal Titanium Nitride Springs.

2. An intelligence unit, the “Bi-planetary Differential”, reads the torque of the spiral spring in the barrel at any time and transmits this information via the “Steering Control Distributor” to the “Automatic Torque Control System”.

3. Next, the “Automatic Torque Control System” uses this information to release the right power on demand at exactly the right time to keep the torque of the spring barrel constant at a chosen level. To activate this important moment, a specially developed trigger is used, the “Instantaneous Double Escapement Trigger”. The challenge is that the energy can release in one step. This sophisticated mechanical system can accumulate the necessary energy during the running of the watch and released it instantaneously when needed.

The fact that this movement was never conceived before made it very difficult for watchmakers to help in its development. Unlike traditional horological development, there was no ancestral knowledge that watchmakers and engineers could base their development on.

The first year of the project was spent mainly on calculation and finding ways to define a system that could manage and control the power of the helicoïdal spring. Because of the complexity and development of new functionalities that were never used in past clockwork development, Philip Lutolf could not pass from the 3D computer construction to the prototyping phase in one step. First, the different functions of the mechanical system were tested separately. In particular, the power generation mechanism, which includes the helicoïdal springs, the power regulation functionalities with its Bi-Planetary Differential, the transmission gears with its Strongnium® Diamond Carbide wheels and Ceramic Bearing Wheels were put on test benches. An additional 18 months were needed to improve and validate the initial 3D construction.

It is only after two and a half years that the team could start the prototyping phase, which will lead then to the production phase. When it comes to making the “movement” work, the watchmakers with their meticulous knowledge enter the scene. Like all watches, the fine mechanics, which are inside, demand an extensive expertise in watch making. Only very experienced watchmakers can make this special movement run.

The intensive collaboration of the inventor, the calculators, the watchmakers, the constructors, the designers and the prototype builder make the success of this watch. Even the smallest change in the movement may have an impact on the final product. This is sometimes visible at first sight, sometimes only in the long run. This factor is indeed very complicated and one of the fascinating aspects of a watch. But the interaction between the design of the watch case and development of the movement is also very close, because in the particular case of the HP-1 the watchcase also has a function in holding the helicoïdal springs. A normal movement base could not withstand the power.

About Philip Lutolf
Philip Lutolf was born in 1967 in Geneva, Switzerland. At an early age Lutolf was always inspired by technical challenges and searched for new and unconventional solutions. During the 1990s, he began to focus more specifically on watch technology. He developed a keen interest in watch components, wheels, dials, cases and watch designs.

This later led him to study watch-making in greater detail.He graduated from the University of St. Gallen in 1991. For ten years he followed an international career working for multinational companies, including one of the leading car manufacturers in Europe. In 2001 he joined a consultancy company and attracted multiple watch companies as clients. He later decided to go back into operative responsibilities and lead a small Geneva watch company.

It was during that last professional experience, that his initial interest in watches and technical challenges got the decisive stimulus. His knowledge of the watch industry and his spirit of research as well as his entrepreneurial ambition initiated the process, which after twenty months of research and development led to the patented invention “Helicoïdal Constant Force” and its application in a new watch movement.

Since 2005 Philip Lutolf has dedicated himself wholly to this development and has worked with a team of engineers and watchmakers on the successful commercialization.

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