Schatz Clock Company aka Jahresuhrenfabrik

Schatz Clock Company aka Jahresuhrenfabrik (Est. Mid 1850s) was founded by August Schatz and Anton Harder in the Black Forest region of Triburg, Germany. It was first registered in 1881 as Schatz & Wintermantel, and was re-structured in 1884 as Jahresuhrenfabrik A.G. It was registered again in1897 as Jahresuhrenfabrik GmbH, and finally in 1923 as Jahresuhrenfabrik August Schatz & Sohne.
The German word, ‘Jahresuhrenfabrik’ means ‘Year Clock Factory’ and is appropriate as the founders committed to producing clocks that could accurately keep time over a long period with a minimum of winding or other maintenance. In the late 19th century, August Schatz worked with inventor Anton Harder with the goal of making an accurate clock that only needed winding once a year. They almost succeeded when they made the 400-day, or Anniversary, clock but it wasn’t as accurate as they’d hoped.
Today, the company is known for two types of clocks with different ‘life spans’ for the winding: the Schatz 400-day clock and the 1000-day clock. This far exceeded the other leading clocks of the time which required winding every week or so. The 400-day clock was a sensation in part because it could be wound once yearly, often in association with a special event like a birthday or other anniversary. This made Schatz clocks ideal for gifts.
Harder sold his patent is 1884 to F.A.L. deGruyter of Amsterdam and they continued the production of Jahresuhrenfabrik clocks, but they allowed the patent to expire.
After it did expire in 1887, several clockmakers in Germany’s Black Forest region began manufacturing torsion clocks that also needed winding only once a year. These companies included Gustav Becker, Kieninger & Obergfell (also known as Kundo), and Lenzkirch, Kienzle, and Junghans. Suddenly, clocks with long running times were being produced en masse.
The long-running capabilities of 400-day clocks relied on the slow turns of a torsion pendulum—often as few as eight per minute—as well as intermediate pinions and wheels between the mainspring barrel and the rest of the movement. Most antique 400-day clocks were constructed with a heavy spherical ball or cylinder-shaped pendulum hanging beneath the movement that would rotate slowly in one direction and then the other.
The pendulum in the 400-day clock was the reason it didn’t need to be wound as often. The pendulum spun at the end of a suspension spring that allowed it to run much longer between windings than the eight days at which most clocks required winding. The initial designs called for a flat-disk pendulum that evolved into the 4-ball pendulum still used today.
Beginning around 1900, these pendulums were generally made from an assembly of three or four brass balls. The entire clock was often positioned under a glass dome, allowing the interior mechanism to be clearly visible and sometimes known as a ‘skeleton movement.’
By the early 20th century, 400-day clocks were popular wedding gifts and their once-a-year winding requirement made them a sentimental anniversary tradition. Other companies took up the challenge of making the 400-day clock more accurate.
American jewelers Bowler and Burdick marketed their 400-day clock as the Anniversary clock by which it became known. The clocks were still relatively inaccurate. Experts conducted experiments to find the best materials from which to make the pendulum since the clocks were easily affected by humidity and temperature changes. The problem was solved when Charles Terwillinger of Horolovar Company invented the Temperature-Compensating Suspension Spring in 1951. This thin spring needed to be tuned perfectly or it could throw off even the best timekeeping-engineering.
Around this time, the company’s clocks mostly used the name ‘Schatz.’ One example is a clock with an attractive and unusual style of bezel around the dial with a wide front section and embossed decoration. The movement has the same gearing as the older Jahresuhrenfabrik movements, but is the first movement with ‘49’ in the circle on the back plate.
In 1954, the Schatz Company developed a new model that would run for 1,000 days. However, the most desirable antique torsion clocks are generally the 400-day models made before 1914 by either Jahresuhrenfabrik or Gustav Becker.
Over its history, the Schatz Clock Company produced cuckoo clocks, barometers as well as 400 day clocks. In later years, it produced electric clocks and battery operated quartz clocks. The company struggled to compete in the early 1980s, and closed down in 1985.
The eight-day cuckoo clocks have one of the most beautiful and clever plate designs in manufactured clocks. Both the front and back plates are cut out to reveal a bird with the eye at the third-wheel pivot-hole position. The rest of the plate resembles a tree with branches. In addition, the center arbor goes through the front plate where the bird’s wings would be. The strike-lifting cams provide the representation of bird wings.
Today, Schatz clocks are most famous for both the 400- and 1000- day versions and are also sought after because many contain a ship’s bell that rings at certain intervals. Attractive and ingenious Schatz clocks continue to occupy shelf and wall space in thousands of homes, boats and buildings the world over. While the company wavered at times, it did achieve notable success and remains one of the top producers for boat clock and for antique collectors and buyers.