Wooden Yoke
6th Floor / No. 20
The Yoke
The bell yoke has evolved significantly throughout history. With the earliest bells, we can see that it was merely a wooden pole to which the bell was attached simply with ropes. Later, yokes began to develop towards today’s shapes.
On one side, it is usually quite low and then rises steeply. It is highest in the middle and then descends symmetrically to the same height as at the beginning. The width itself is conditioned by the construction, while the thickness is determined by the crown, with the help of which the bell is attached to the yoke.
The shape of the yoke changed with historical periods. At first, the shapes were very simple (sometimes just a small “hump”). Later, however, it ascended to distinctly decorated forms, as can be seen in Ptuj.
What wood are they made of and why?
Yokes in our region are mostly made of oak wood, and occasionally we find larch ones. For yokes, we want wood that is sufficiently solid, does not “breathe” (expand/contract) too much throughout the seasons, and is not too prone to warping and cracking. Throughout history, oak and larch have proven to be sufficiently reliable.
Toothed Carriers and Ball Bearings – Pros and Cons of Different Bell Mounting Methods
In the past, bells were mounted on the structure using so-called “toothed carriers”. This involves a gear-like piece, which has a gear segment on the yoke, and its negative on the wooden structure. The bell “rocks” along the teeth. Just like the shape of the bells themselves, the yokes, and clappers, the methods of mounting them to the structure have also changed significantly.
At first, a round axle was embedded in the yoke, and a notch/hole was drilled or cut into the structure where the axle then sat. This system was prone to wear, and due to high friction, it was very difficult to drive especially larger bells. Our ancestors solved wear in various ways. Initially, they placed a metal plate shaped to the axle in the notch in the wood, and later castings similar to plain bearings. Since the bell was still hard to drive due to friction, they continued and first made a “wedge” mount. The axle, which had a rectangular forged wedge shape, stood with its pointed part in a cup shaped into its negative. Thus, a shape similar to a “toothed carrier” appeared for the first time.
Later, the wedge was reshaped into two teeth, three teeth, or more. The more teeth there were, the nicer and smoother the bell rocked. Toothed paws reached the peak of development in the bell foundries of Peter Hilzer in Vienna and here at the Carniolan Industrial Company in Jesenice, which manufactured steel bells. The last forms of this kind were shaped practically identically to a quarter of a gear. One quarter on the structure and the other on the yoke.