Eng-Tips is the largest engineering community on the Internet
Intelligent Work Forums for Engineering Professionals
-
Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!
Braking force
- Thread starter mekafime
- Start date
BrianPetersen
Mechanical
Gravity?
Are you talking about the force encountered during the normal slowing of the elevator to a stop at each floor, or are you talking about what might happen if the emergency brake is applied?
Does the brake have a rated load? More to the point, does it have any means of modulation the way the brake pedal does in your car (you or something presses harder, and the brake applies more force), or is it simply "on" or "off"? What are the implications of that? I know what the answer is, but I'm trying to get you to think about how the device works.
What's the factor of safety between the load capacity of the elevator (including the carriage itself), and the capacity of this brake?
What's the manufacturer say?
Are you talking about the force encountered during the normal slowing of the elevator to a stop at each floor, or are you talking about what might happen if the emergency brake is applied?
Does the brake have a rated load? More to the point, does it have any means of modulation the way the brake pedal does in your car (you or something presses harder, and the brake applies more force), or is it simply "on" or "off"? What are the implications of that? I know what the answer is, but I'm trying to get you to think about how the device works.
What's the factor of safety between the load capacity of the elevator (including the carriage itself), and the capacity of this brake?
What's the manufacturer say?
- Thread starter
- #3
Hello, I am evaluating an elevator tower. The tower mast shows displacements not contemplated and produces premature wear in the pieces, so they asked me to calculate the structure, I already have almost all the loads according to the corresponding standards and I still need to calculate the braking force product of the deceleration in each floor.
goutam_freelance
Mechanical
Depending on your elevator configuration in simple terms (while descending):
Max. Braking force (F)=effective mass X(max deceleration+ g)
Max deceleration will depend on braking distance and max velocity.
Engineers, think what we have done to the environment !
Max. Braking force (F)=effective mass X(max deceleration+ g)
Max deceleration will depend on braking distance and max velocity.
Engineers, think what we have done to the environment !
Isn't this somewhat dictated by the rack and pinion drive speed for the elevator; I assume that this is the same elevator from your other posting, so you have 2000-kg elevator dead load.
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
Start with the amount of kinetic energy you need to convert: KE = 0.5mv^2.
Determine distance in which you want the elevator to stop. If you use time, use that to calculate distance travelled. Divide ΔKE by distance and you have braking force, which will be a very large number. (If you are using speed or time-to-stop, you can determine stopping distance.)
This is the horizontal case. add weight of elevator to braking force to balance KE added by elevator's downward travel.
Determine distance in which you want the elevator to stop. If you use time, use that to calculate distance travelled. Divide ΔKE by distance and you have braking force, which will be a very large number. (If you are using speed or time-to-stop, you can determine stopping distance.)
This is the horizontal case. add weight of elevator to braking force to balance KE added by elevator's downward travel.
- Thread starter
- #8
- Status
Similar threads
- Locked
- Question
- Locked
- Question