Dashpots are mechanical devices that slow movement by resisting the force applied against them and absorbing energy. Most dashpots are equipped with a spring to help them function. There are two common types of dashpots. Linear dashpots are measured by linear displacement and damping coefficient, while rotary dashpots measure damping coefficients in torque per angular velocity.

Dashpots are often used in door closers, to prevent the door from slamming shut, as well as consumer electronics. Additionally, dampshots can be used in devices to prevent doors from swinging open abruptly. They are also used in shock absorbers and dampers.

1. Most dashpots require lubrication, like oil, which will have to be periodically replenished. Air-based dashpots are among the few which do not require lubrication.

2. Dashpots reduce impact noise and wear. Constant impact is noisy and wears out machinery quickly. Dashpots not only prevent the loud impact, but also slow the impact down, lessening stress on your parts.

3. Dashpots are one of the most efficient and cost-effective methods of damping. They are easy to maintain and inexpensive to install.

Action Steps
The best contacts and resources to help you get it done

Buy a rotary dampening dashpot for heavy-duty applications

Makers of dashpots often offer rotary dashpots for machines that are in constant motion, or those that require heavy damping. This includes most types of manufacturing machinery and consumer products that receive heavy use. Rotary dashpots often require lubrication with oil or other liquids to help keep them running smoothly.

I recommend: Purchase a model from Energy Kinetics or contact Ace Controls to ask about its rotary models.

Use linear motion control dashpots for smaller jobs

A linear dashpot expands and compresses in a straight line, instead of rotating like a rotary dashpot. These can be air or liquid-based and are often used for jobs that require less stress reduction and slowing. Many consumer products use linear dashpots to gently move parts and open doors. Linear dashpots can be very small and are used for delicate operations.

I recommend: Get a linear air dashpot from ITW Delpro, or check out Deschner's model.

Buy air damping dashpots for specialized working environments

Air damper dashpots don't require lubrication, and can be used in places where extreme temperatures or clean operations don't allow lubricant-based dashpots. This kind of dashpot has a long life span but is usually only used for low kinetic energy and low forces needs. This makes it less suitable for heavy equipment.

I recommend: Check out Airpot's air dampening dashpots or buy an air damper dashpot from Isotech.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  If you're focused on continuous damping, measure your model using the force acting on the dampshot. If impact absorption is more important, measure the model by the kinetic energy you need damped. Most dashpot manufacturers will provide charts with this information on their websites. If not, be sure to contact them and ask.