||It has been suggested that this article be merged into Pruning shears. (Discuss) Proposed since January 2015.|
In contrast to anvil pruners, on bypass pruners the material rests on a counter base, the counter blade. A blade is also pushed through the material during the cutting action. However the blade slides past (bypasses) the counter blade.
Anvil pruners push a blade through the material. This is the opposite of a bread knife, which uses a drawing cut because the blade is drawn through the material (in this case the bread).
With anvil pruners the blade moves freely through the material without resting against an opposite blade or similar.
At the end of the cut, the blade's cutting edge is resting on the anvil. The anvil is made of a material softer than the blade, so that the blade is not damaged when it meets the anvil. Suitable materials for the anvil are plastic, aluminum, zinc, brass, or bronze alloys.
On an anvil pruner, proper cutting is assured even if the blade swerves slightly to the left or right during cutting. As long as the blade meets the anvil at the end of the cut and fits tightly against it, the material is separated. For a bypass pruner, the blade must always fit tightly against the opposite blade, or the material will not be cut through.
For this reason, the blades of anvil pruners can be ground thinner than those on bypass pruners. The thinner a blade is ground, the less the width of the split it makes in the material and accordingly the lower is the force required for cutting. Due to their thinner blades, anvil pruners are cutting easier than bypass pruners. This makes them particularly well suited to cutting thick branches and hard wood.
The LÖWE principle – a drawing cut made against a fixed support – combines a drawing cut with a pushing cut. This is possible because the blade lever and base lever are connected by an eccentric bearing. When the pruners are open, the blade is longer than the anvil thanks to the eccentric bearing. When the pruners close, the blade draws back slightly while it pushes through the material. This reduces the cutting force needed to make a cut still further.
The world's first anvil pruners were developed and produced in 1923 by Walther Schröder in Kiel, Germany. The pruners were given the product name "Original LÖWE" and were distributed internationally as far back as 1925. Other companies are producing anvil pruners, include Bahco, Edma, Felco, Fiskars Gardena and Wolf Garten.