| Homepage - Contents - M. Automatic Quartz Watch | < Previous page | Next page > |
| 1957 | On January 4th Kieninger & Obergfell of St. Georgen in Schwarzwald file a patent application in Germany for a watch with electric generator. The generator consists of a rotating mass equipped with permanent magnetic poles, surrounded by eight stationary electric coils. The moving magnets induce alternating currents in the coils. Those currents are rectified and used to charge an accumulator, which supplies a small motor. It remains unknown whether the generator watch was ever produced. In later patent applications by Kieninger & Obergfell, of February 6th and May 24th, many (electro-) mechanical and electronic details are described. Fritz Thoma is mentioned as the sole inventor. |
| 1958 | On May 12th, Uhrenfabriken Gebr/der Junghans A.G. in Schramberg, Germany, file a patent application in Germany for a high-efficiency generator driven by a rotating mass, to be used in wrist watches. To improve the output, the generator speed is increased with a gear transmission. Evidence of production of this generator is lacking. |
| 1972 | ETA files a Swiss patent application for an automatic watch with mechanical spring, in which balance and escapement have been removed and replaced by a small generator. The generator is driven from the main spring, while its speed is controlled by a quartz oscillator. The generator is electrically switched between two conditions: charging a capacitor (whichrepresents a relatively light mechanical load) or short-circuited stator coil (which means a brake action). The IC and the quartz are supplied from the capacitor. The watch did not reach the production stage. The code name of the system is Gnomon; this name is used again for a system invented by Kinetron and adopted by ETA in 1991. |
| 1975 | On April 12th, a patent application, no. 52-68466, is filed in Japan by Suwa Seikosha for an automatic quartz watch. Its simple concept reflects the heart of the present AGS watch by Seiko: a rotating mass drives a Lavet generator via a multiple stage gear transmission. |
| 1976 | Sicura presents the 'Superman' at the Basle Fair. This is an automatic watch, with an electronic module and a LED display plus a dial with hands. The spring of a mechanical movement is wound by the rotating mass and charges the battery for the LED module indirectly. Further details about the functioning of this watch are unknown. |
| 1978 | The introduction in Japan of the double-layer supercapacitors consisting of active carbon ('Supercap' by Matsushita and the 'Goldcap' by NEC) makes it possible to produce automatic quartz watches which do not suffer from the life-restrictions of rechargeable batteries. It takes, however, some years before the watch industry succeeds in exploiting the new device in the form of a 0.33 Farad button cell. |
| 1978-1983 | Frits Bettink in Buren, Holland, studies the principles of an automatic quartz watch. As application for an official patent is too costly for him, he decides to publish in the Dutch watch periodical Chronos in January 1983. |
| 1982 | On September 3rd, P.M.J.Knapen, a watchmaker in Tilburg, files a patent application (no. 8203443) in the Netherlands for an automatic quartz watch. In a revised international application (PCT/NL83/00034) submitted one year later, the rotating mass and the rotor of the generator are coaxially mounted on a shaft. The generator is constructed as a claw-pole generator, i.e. as a miniaturized bicycle dynamo. The complete system consisting of an eccentrically rotating mass, microgenerator, diodes and accumulator should fit within the volume of a button cell for quartz watches. Unfortunately for Knapen a patent search makes clear that the basic principles of the automatic quartz watch have already been patented several times since 1957. In spite of the many interesting elements in Knapen's application, the heart of the matter has been anticipated by Kieninger & Obergfell, Junghans and many others. |
| 1984 | On July 3rd, Kinetron B.V. in Tilburg files an application in the Netherlands (no. 8402113), followed by a European application. In 1989 the European patent (no. 0170303) is granted. Sole inventor is the earlier mentioned P. Knapen. The patent relates to "an electric power supply system (etc.), comprising an AC generator (etc.) characterized in that an accelerating transmission with loose coupling is arranged between the rotating mass and the rotor wheel (etc.)", said transmission and coupling merely consisting of a tiny spiral spring plus the magnetic detent torque between the stator and rotor of the generator. The patent does not claim the automatic quartz watch as such, but "the accelerating transmission with loose coupling" between mass and generator. This surprisingly simple transmission 'kicks' the rotor to a high rotary speed instead of acting as an accelerating gear transmission. Mathieu Knapen of Kinetron B.V. developed the patented system in co-operation with Paul Goemans of the Eindhoven University of Technology. The automatic quartz watch which makes use of the original system is the 'Samara' of Jean d'Eve, La Chaux-de-Fonds in Switzerland. Its movement was designed in 1988 by Michiel Groothuis, a Dutch employee of Conseilray, consultants on watch technology in La Chaux-de-Fonds. |
| 1986 | Seiko introduces world's first analogue quartz watch without battery (caliber 8T23), which obtains its energy from a microgenerator driven with a winding knob. To supply the supercapacitor with enough energy for 3 days, several minutes of winding by hand are required. |
| 1988 | In February, the first automatic quartz watch 'Seiko AGS' (Automatic Generating System, caliber 7M22) is introduced by Seiko at the watch and jewellery fair 'Inhorgenta' in Munich, Germany. Eleven models of the watch are retailed in the same year. To celebrate its centennial, 'Le Phare-Jean d'Eve', a watch firm in La Chaux-de-Fonds, shows the 'Samara' at the Basle Fair in April. The watch and its packing are pieces of art designed by Jean-Francois Donzé of Le Phare-Jean d'Eve. |
| 1990 | On September 7th, Kinetron files an application for a patent on a "generator for miniature power consuming devices in particular", with several improved versions of the "trans-mission with loose coupling". The Dutch application (no. 9001976) is later followed by an international one (PCT/NL91/00145). The main improvement consists of the addition of a freewheel coupling. In this way the transmission between rotating mass and generator is provided with a second loose coupling. The earlier tiny spring is replaced by a much larger one, in order to increase the energy output in most circumstances. |
| 1991 | Seiko cal. 5M22 and 5M25, in which generation efficiecy was improved, go on sale. |
| 1992 | An improved version, the 'Kinetic' caliber 5M23 is developed by Seiko. |
| 1994 | The ladies' 'Kinetic' is launched by Seiko, caliber 3M. |
Copyright © by Pieter Doensen
email: doensen@xs4all.nl
All rights reserved. No part of this work may be reproduced or used in any forms or by any means - graphic, electronic or mechanical, including (but not limited to) photocopying or information storage and retrieval systems - without written permission from the copyright holder.