Wales and Marches Horological Society :
For people interested in horology: clocks, watches, scientific instruments, barometers or just the passing of time!
20th Century “Windmill” Jockele Clocks
Traditionally, Jockele clocks are miniature weight powered, wooden framed clocks, with movements about 8cm tall and 6cm wide, made between the 1790s and the early 20th century in the Black Forest area of Germany. However, in the first few years of the 20th century an enterprising German clock manufacturer (as yet unidentified) designed and made the first mass-produced brass plated version of these small movements.
This movement’s design fig.1 has been refined and copied by
other manufacturers since then, and in Germany, the small
one-day duration souvenir and novelty wall clocks which use
this type of movement are still known as ‘Jockele clocks’.
Although Black Forest makers have a tradition of incorporating
automata into clocks, I have found no 19th century precedent
for windmill sails attached to an extended escape wheel arbor.
The earliest of these clocks seems to date from the
1920s to 1930s; it was probably a new marketing idea, aimed at
the tourist souvenir sector, in both Germany and Holland.
Many incremental production simplifications and improvements
were introduced to the design of both movements and their dials
over the 80 years or so that these clocks were manufactured.
One design modification (unfortunate, from the point of view
of the repairer) was the abandonment of conventional
plate pillars with nuts securing the back plate to the front plate,
and the adoption of pressed steel plate pillars with ‘twist-tabs’ fig.1
(fig. 2 and 3).
Once the wheels and pallets were in position in the front plate, these ‘tabs’ fitting through slots in the back plate; the tabs were then twisted slightly, to secure the back plate into position. In the course of repair, these ‘tabs’ are straightened again to dismantle the movement, and then re-twisted after reassembly. Sometimes the metal of the tabs is significantly weakened or even torn by the time a windmill clock reaches my hands, 50 to 70 years later. I believe that from a repairer’s viewpoint today, the ‘tabs’ are better left flat once a movement has been dismantled, they can then be drilled to take clock pins on reassembly.
fig.2 fig.3
The earliest clocks have the design outline ‘pressure moulded’ into the surface of the three-ply dial sheet, and the brightly coloured dials were then hand painted (figs. 4 and 5 from the 1930s and 40s).
fig.4 fig.5
Later clocks have colour printed dials (fig. 6 from the 1950s – 60s), and the latest clocks have a redesigned movement with plastic hands, like this one from the 1980s (fig. 7).
fig.6 fig.7
It seems that production of these weight powered one-day windmill clocks probably ceased sometime in the first decade of the 21st century, although it is still possible to buy a miniature one-day duration spring powered version of this style of wall clock. Like the windmills themselves, I believe these little windmill clocks are now ‘heritage’ items!