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Dashpot

technology Maturity 9-11

A dashpot helps things move slowly.

Dashpot.svg
Dashpot.svg
It can stop a door from slamming. It makes the motion soft and gentle. This keeps things safe for you. It is very helpful! Do you see things that move slowly?

38 words

A dashpot helps things move slowly.

Dashpot.svg
Dashpot.svg
It resists motion to stop things from slamming. It can turn movement into heat.
Dashpot.svg
Dashpot.svg

Many dashpots use a thick liquid. This liquid makes the motion soft. It can work with a spring. This helps control how things move.

Some dashpots work in a line. Others work by turning.

strombergcarb2.jpg
strombergcarb2.jpg
Some even use magnets to slow things down.

Dashpots help keep doors from hitting hard. They also help cars ride on bumpy roads. They even help big bridges stay steady.

They can make a door open fast. Then, they make it close slowly. This keeps everything gentle and safe.

106 words

A dashpot is a tool that resists motion. It helps slow things down. This device is also called a damper.

Dashpot.svg
Dashpot.svg

Dashpots work by absorbing power. They turn motion into heat. Most dashpots use a thick liquid. This liquid makes it hard to move quickly. Some dashpots move in a straight line. These are called linear dashpots. Others work by turning. We call these rotary dashpots.

strombergcarb2.jpg
strombergcarb2.jpg

One type uses magnets. It is an eddy current damper. It uses a large magnet inside a tube. This helps balance scales move to a stop quickly. Some dashpots can work in only one way. They let a door open fast. Then, they make the door close slowly. This stops the door from slamming.

Dashpots are used in many places. They are in shock absorbers for cars. This helps cars ride on bumpy roads. They are also in big bridges. These parts help bridges stay steady during wind or earthquakes. They can even be used in engines.

Dashpot Symbol.svg
Dashpot Symbol.svg

166 words

A dashpot is a clever mechanical device. It is also known as a damper. Its main job is to resist motion. It does this through a thing called viscous damping. This means it uses a thick liquid to slow things down. When a dashpot works, it absorbs energy. It turns kinetic energy, which is the energy of motion, into heat. This helps keep things from moving too fast or too wildly.

Dashpot.svg
Dashpot.svg

How does a dashpot actually work? The force it makes is proportional to the speed of the movement. This force always acts in the opposite direction of the motion. This helps slow the object down. Many dashpots work with a spring to control movement. Some are linear dashpots that move in a straight line. They are measured by their stroke and a damping coefficient. Other types are rotary dashpots that resist turning or torque.

Dashpot Symbol.svg
Dashpot Symbol.svg

There are many different ways to build these tools. Vane dashpots use vanes that move through a thick fluid. This creates a lot of damping torque. Continuous rotation dashpots use a rotor and a stator. They use friction from the fluid to create a small damping force. Another type is the eddy current damper. This uses a large magnet inside a metal tube. It is a great way to make balance scales stop moving quickly without friction.

strombergcarb2.jpg
strombergcarb2.jpg

Dashpots are used in many parts of our world. You might find them in door closers. They stop doors from slamming shut by forcing fluid through a small hole. They are also in car shock absorbers. These cushion the ride against bumpy roads. Engineers even use large dashpots on bridges and buildings. They protect these huge structures from wind or earthquakes. In London, they were used to help fix the Millennium Bridge after it wobbled.

strombergcarb2.jpg
strombergcarb2.jpg

These devices help us understand how different materials behave. Scientists use dashpots to model things like muscle tissue. This is called viscoelasticity. It helps them study how solids change over time under stress. Dashpots can even be used in electrical tools. They can act as timers for things like staircase lighting. They can also help engines run more smoothly. From tiny electronics to giant bridges, dashpots help keep the world steady.

Dashpot Symbol.svg
Dashpot Symbol.svg

375 words

A dashpot, which is also known as a damper, is a mechanical device designed to resist motion. It achieves this through a process called viscous damping. When an object moves, the dashpot creates a resistive force that acts in the opposite direction of that motion. This force is proportional to the velocity, or the speed of the movement. As the device works, it absorbs kinetic energy, which is the energy of motion. This energy is then converted into heat.

Dashpot.svg
Dashpot.svg
Dashpots are essential for controlling movement and are often used alongside springs in dynamic systems.

The mechanism of a dashpot relies on the relationship between speed and resistance. In a typical setup, the force produced by the dashpot is directly related to how fast the object is moving. This relationship is often described as being linear. In a linear system, the output force, denoted as F, is proportional to the velocity, denoted as v. Engineers use a constant of proportionality, often labeled as c, to define this relationship. However, real-world dashpots are frequently non-linear. In these cases, the force is proportional to the velocity raised to an exponent, known as alpha. This exponent can vary between 0.2 and 2.0. Because of this complexity, engineers must use numeric methods rather than simple calculus to analyze non-linear dampers.

There are several distinct types of dashpots categorized by how they move. Linear dashpots, or linear dampers, exert force against translation movement, which is movement in a straight line. These are usually specified by their stroke, the amount of linear displacement possible, and their damping coefficient.

Dashpot Symbol.svg
Dashpot Symbol.svg
Rotary dashpots are different because they oppose torque, which is a twisting force. These are measured by torque per angular velocity. Within the rotary category, there are two main kinds. Vane dashpots use one or multiple vanes moving through a viscous fluid. These vanes move through calibrated openings to provide a significant damping torque over a limited angular range. Continuous rotation dashpots allow for unlimited rotation angles. They provide a smaller damping coefficient by using friction from shearing forces in the fluid between a rotor and a stator.

Another specialized version is the eddy current damper. This device is less common but very effective for specific tasks. It uses a large magnet placed inside a tube made of a conducting but non-magnetic material, such as copper or aluminum. Like a viscous damper, it produces a resistive force proportional to velocity. Because it is a frictionless method when near rest, it is a perfect choice for balance scales. This allows the scales to come to a quick and steady rest without the wear of physical contact.

Many dashpots are designed for one-way operation to allow for versatility. This means the device can permit fast, unrestricted motion in one direction while providing slow, controlled motion in the other. For hydraulic dashpots, this is done using a one-way check-valve. This valve allows fluid to bypass the constriction during fast movement.

strombergcarb2.jpg
strombergcarb2.jpg
Non-hydraulic rotary dashpots might use a ratcheting gear to achieve this same effect. A common example is a door closer. A spring provides the force to close the door, but the dashpot forces the fluid through an orifice to ensure the door closes slowly instead of slamming.

Dashpots serve critical roles in many different industries and technologies. In the automotive industry, they are key components in shock absorbers. These devices cushion a vehicle against vibrations from uneven road surfaces. They are also used in carburetors, such as the Zenith-Stromberg, to cushion the return of the throttle lever.

strombergcarb2.jpg
strombergcarb2.jpg
This helps reduce emissions by allowing the throttle to close slowly. In much larger scales, dashpots are used to arrest steam catapults on aircraft carrier decks. They are even used in electrical switchgear. In these systems, they can reduce reaction speeds to brief events, preventing false-triggering during transients.

Beyond mechanical movement, dashpots are vital in structural engineering and science. Large dashpots are added to buildings and bridges to protect them from wind vibrations and earthquakes. A famous example occurred with the Millennium Bridge in London. After the bridge was found to wobble when people walked on it, repairs were made using such technology. Scientists also use dashpots to model viscoelasticity. This is the behavior of materials like muscle tissue. By using Maxwell and Kelvin–Voigt models, which combine springs and dashpots in series or parallel, researchers can model complex behaviors like stress relaxation and creep.

734 words
🖼️ Images & Media (3)
File:Dashpot Symbol.svg
Dashpot Symbol.svg
File:Dashpot.svg
Dashpot.svg
File:strombergcarb2.jpg
strombergcarb2.jpg
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