What is an NEA jagged pneumatic clutch?

It is an entirely compact unit of pneumatic clutch and disengagement by spring reaction. With a radial type power, its clutch must be produced at low speed or even completely at rest (unlike disengaging, which can occur at any rate).

The fact of being jagged allows transmitting large pairs and, when it is necessary to keep synchronism, the possibility of manufacturing it to be positional.