Constant torque spring - damping question

In summary, the problem Hallo is facing is that he needs a slow rotation of the drive wheel whenever the drive wheel is not driving the Geneva wheel of the Geneva mechanism. However, when the pin of the drive wheel rotates the Geneva wheel by 90 degrees, he needs a lot of torque because there is a load connected to the Geneva wheel. He thinks that a rotary damper can help him slow down the rotation of the drive wheel, but when getting to the point of rotating the Geneva wheel, he would need the damping to be gone (because there, he needs full torque).
  • #1
DaanW
2
0
Hi all,

I have a constant torque spring that rotates the drive wheel of a Geneva mechanism. I am facing the following problem. I would like a very slow rotation of the drive wheel whenever the drive wheel is not driving the Geneva wheel of the Geneva mechanism (which is 270 degrees of a rotation). However, when the pin of the drive wheel rotates the Geneva wheel by 90 degrees, I need a lot of torque because there is a load connected to the Geneva wheel. Therefore, I need to use a high torque constant torque spring (7.50 in-lbs.).

I think that a rotational damper can help me slow down the rotation of the drive wheel (it is a timing mechanism, and the rotational velocity should be ~1 rpm), but when getting to the point of rotating the Geneva wheel, I would need the damping to be gone (because there, I need full torque).

Does anyone have a suggestion for a rotary damper that is capable of doing this? Or are there other ideas/designs that can solve the same problem in your opinion?

Thanks in advance!
 
Engineering news on Phys.org
  • #2
Hallo Daan, :welcome: !

How about a kind of flywheel to even out the irregularity of the angular momentum required ?
 
  • #3
Do you need a change in rotation speed; if not, a liquid rotary damper will not prevent the mechanism from delivering its full torque, it will only limit the rate at which the torque can be delivered.
 
  • #4
It's not logical to dampen the drive wheel for 3/4 of the time: waste of energy.
Still in favour of the flywheel idea :rolleyes: - but even that has air resistance; perhaps it's better to use a heavy drive wheel that slows down during 1/4 turn of work and revs up 3/4 turn ?
 
  • #5
If you are using a constant force spring for the full rotation then there is no waste of energy if you slow the rotation for the 3/4 portion.
 
  • #6
Thanks for the replys. An additional constraint is that the component can't be any bigger than 1 inch diameter.. I think I can solve the problem by using a rotary damper, only problem now is to find one that can resist a ~1 N*m torque and bring the rotational speed down to ~1-2 rpm. Let me know if you have a design/manufacturer for such a component. Many thanks!
 

1. What is a constant torque spring and how does it work?

A constant torque spring is a mechanical spring that provides a constant amount of torque throughout its range of motion. It works by using a tightly wound coil of wire that applies a torque force when twisted. This torque force is proportional to the amount of rotation, providing a consistent level of force.

2. What is the purpose of a constant torque spring?

The purpose of a constant torque spring is to provide a constant level of torque or force in a mechanical system. This can be useful in applications where a consistent force is needed, such as in various types of machinery, tools, and equipment.

3. How is a constant torque spring different from a regular spring?

A regular spring provides a varying amount of force depending on its level of compression or extension. In contrast, a constant torque spring provides a consistent level of force throughout its range of motion. This is achieved by the tightly wound coil design and the use of materials with specific torque characteristics.

4. Can a constant torque spring be used for damping?

Yes, a constant torque spring can be used for damping. Damping is the process of reducing or eliminating the vibrations or oscillations of a system. A constant torque spring can provide a smooth and consistent force that can help dampen the vibrations in a mechanical system.

5. What are some common applications of constant torque springs?

Some common applications of constant torque springs include automotive components, household appliances, medical devices, and various types of machinery and equipment. They are also commonly used in adjustable torque wrenches, door closers, and tensioning devices.

Similar threads

Designing a Geneva Mechanism: Overcoming Challenges
    • Mechanical Engineering
Replies
5
Views
2K
My weird geneva mechanism doesn't work. Looking for suggestions
    • Mechanical Engineering
Replies
3
Views
933
Seeking ideas for how to achieve an adjustably damped shaft connector
    • Mechanical Engineering
Replies
6
Views
1K
Maintain a constant velocity for a rotating wheel
    • Mechanical Engineering
Replies
4
Views
1K
Torque and power calculation for a crank wheel
    • Mechanical Engineering
Replies
5
Views
2K
Motor specifications to drive Motorcyle Carousel
    • Mechanical Engineering
Replies
1
Views
840
What makes a connecting rod turn a crank one way?
    • Mechanical Engineering
Replies
9
Views
2K
Torque created around offset wheel
    • Mechanical Engineering
Replies
8
Views
1K
Specified Torque Specs on Automotive Fasteners -- Required or just suggestions?
    • Mechanical Engineering
Replies
10
Views
991
Torque calculations: Rotating vertical shaft
    • Mechanical Engineering
Replies
5
Views
3K

Hot Threads

Recent Insights

Back
Top