Both the Chuck Capper and the Spindle Capper machines pretty much share the same elements. Both have a bulk storage hopper for the caps, an un-scrambler or sorting system to orient the caps into the right side up position before placing them on the down feed ramp, an infeed conveyor that can grip the container of the bottle firmly to resist turning as the cap is screwed down and tightened onto the container, and that is where the similarity ends.

Chuck type cappers grip the cap in a manner very similar to that of the common electric drill. A cap is presented to the chuck, it grips it and then rotates it as it descends on the bottle mouth and screws it down until resistance sensors detect the correct amount of back pressure from tightening and the cycle is stopped to begin again. These machines can place and tighten caps with precision threads that require careful alignment such as on Pharmaceutical containers. Resina makes the machine you see above. This is one of the most popular brands of capping machine ever made and it comes in many styles. I have worked on them all.