How Does A Chuck Capper Work?

We recently briefly explained the process used to tighten caps using a spindle capper. Chuck cappers offer an alternative to spindle capping for screw-on, or continuous thread, type closures. Whether a spindle capper or a chuck capper is the better solution for any packaging project using a threaded closure will depend on several factors unique to each project. Below we take a look at how the chuck cappers tighten screw-on type caps and how it differs from the spindle capper.

Chuck capping machines are so named because they use a chuck, with or without an insert, to apply torque to the continuous thread closures. Unlike the spindle cappers, where spinning disks contact the outside of the cap to tighten the closures, the chuck will descend and cover the cap, then spin the cap to apply torque to the desired level.

Like the spindle capper, the chuck capper will employ several stability components to ensure consistent and reliable tightening. However, the range of different caps is slightly lower than the spindle capper due to the chuck descending over the cap. So while the chuck capper can tighten typical screw-on type lids like those seen on bottled water and other beverages, including sports caps, it becomes more difficult to tighten closures with a chuck capper when using a trigger sprayer or pump type closure, for example.

The automatic chuck capper will use a cap delivery system to provide the caps to the bottles as they enter the capping area. The delivery system will typically consist of a cap elevator or vibratory bowl, which will reject caps that are not properly oriented for the capping machine. The delivery system moves caps to a chute, which then holds properly oriented caps in place for presentation to the bottle.

Most automatic chuck capping machines will then use starwheel indexing to stabilize bottles during the capping process. A starwheel can be thought of as a wheel with a specific number of cuts in it to hold bottles, giving it the appearance of a star. As bottles move into the starwheel from the conveyor system, they will be moved around the wheel. The chute will normally sit at an early point on the starwheel, allowing the bottles to collect a cap as it moves under the chute. The starwheel will stop and go as bottles move around the indexing system. The stopping points along the wheel will be programmed to halt bottles under one or more chuck heads on the capping machine. When in place, and stabilized by the starwheel cut, the chuck heads will descend and apply torque to the desired level. Capped bottles then continue around the starwheel to be released back to the power conveyor, moving to labeling, coding or other packaging tasks.

Chuck cappers are also available as semi-automatic machines as well, and at the semi-automatic level arguably outperform the semi-automatic spindle capper. Semi-auto spindle cappers are usually used when a smaller packager has a unique cap, such as the trigger or pump sprayers mentioned above. Semi-automatic chuck cappers range from simple handheld machines to user assisted tabletop and portable machines. Depending on the process, the semi-automatic chuck cappers can add speed to the capping process. Like the semi-automatic spindle capper, operator assisted chuck capping machines will add to the consistency and reliability of the capping process while removing the danger of repetitive motion injuries to employees who spend an entire shift hand-capping and tightening closures.

Spindle cappers and chuck capping machines provide two unique solutions for tightening screw-on type closures. To learn more about either of these machines, browse the Capping Machine section of the Liquid Packaging Solutions website or contact LPS today for help determining which capper is best for your own project.