Pneumatic muscle

Pneumatic muscle – diaphragm contraction drives

Pneumatic muscles are diaphragm actuators, or more precisely diaphragm-contraction actuators, also known as pull actuators. They were developed according to the model of a biological muscle and consist of contractible tubing and appropriate connectors. The contractible tubing is made up of a rubber sheath with a non-crimped fabric made of aramid fibres on the inside. The diaphragm hermetically seals the operating medium. The fibres provide reinforcement and transmit power. When internal pressure is applied, the diaphragm extends in circumferential direction. This creates a tensile force and contracts the tubing lengthwise. The maximum usable tensile force is available at the start of the contraction and then decreases with the stroke. The advantages: The diaphragm actuator has an outstanding force-to-weight ratio and is powerful in operation. It is also free of stick-slip effects and its initial force is 10 times higher than comparable pneumatic cylinders.