The CNA series locking cylinder, manufactured by SMC Corp. of America, Indianapolis, uses an integral, compact lock unit that is unaffected by the quality of the supply air. A manual override lock release is available as a standard feature, and the series is available in 5 bore sizes from 40 mm to 100 mm. Typical applications include intermediate stops, emergency stops, and drop prevention.
The lock unit design utilizes a tapered wedge and two rows of precision steel balls to evenly distribute the locking force to the cylinder's piston rod. By isolating the locking components from the supply air pressure, poor air quality (such as contaminants and moisture) will not affect the performance of the lock mechanism. Also, a standard manual override allows the lock to be released in the absence of supply pressure. The lock can be applied either during cylinder extension or retraction.
In addition to the tie-rod style CNA series, SMC also offers inter-mediate-stroke locking cylinders in compact, round body, guided, and rodless cylinder designs. Cylinders with integrated end-lock mechanisms are also available.